Tag Archives: stage

Showtime Seeks Injunction to Stop Mayweather v McGregor Piracy

Post Syndicated from Andy original https://torrentfreak.com/showtime-seeks-injunction-to-stop-mayweather-v-mcgregor-piracy-170816/

It’s the fight that few believed would become reality but on August 26, at the T-Mobile Arena in Las Vegas, Floyd Mayweather Jr. will duke it out with UFC lightweight champion Conor McGregor.

Despite being labeled a freak show by boxing purists, it is set to become the biggest combat sports event of all time. Mayweather, undefeated in his professional career, will face brash Irishman McGregor, who has gained a reputation for accepting fights with anyone – as long as there’s a lot of money involved. Big money is definitely the theme of the Mayweather bout.

Dubbed “The Money Fight”, some predict it could pull in a billion dollars, with McGregor pocketing $100m and Mayweather almost certainly more. Many of those lucky enough to gain entrance on the night will have spent thousands on their tickets but for the millions watching around the world….iiiiiiiit’s Showtimmme….with hefty PPV prices attached.

Of course, not everyone will be handing over $89.95 to $99.99 to watch the event officially on Showtime. Large numbers will turn to the many hundreds of websites set to stream the fight for free online, which has the potential to reduce revenues for all involved. With that in mind, Showtime Networks has filed a lawsuit in California which attempts to preemptively tackle this piracy threat.

The suit targets a number of John Does said to be behind a network of dozens of sites planning to stream the fight online for free. Defendant 1, using the alias “Kopa Mayweather”, is allegedly the operator of LiveStreamHDQ, a site that Showtime has grappled with previously.

“Plaintiff has had extensive experience trying to prevent live streaming websites from engaging in the unauthorized reproduction and distribution of Plaintiff’s copyrighted works in the past,” the lawsuit reads.

“In addition to bringing litigation, this experience includes sending cease and desist demands to LiveStreamHDQ in response to its unauthorized live streaming of the record-breaking fight between Floyd Mayweather, Jr. and Manny Pacquiao.”

Showtime says that LiveStreamHDQ is involved in the operations of at least 41 other sites that have been set up to specifically target people seeking to watch the fight without paying. Each site uses a .US ccTLD domain name.

Sample of the sites targeted by the lawsuit

Showtime informs the court that the registrant email and IP addresses of the domains overlap, which provides further proof that they’re all part of the same operation. The TV network also highlights various statements on the sites in question which demonstrate intent to show the fight without permission, including the highly dubious “Watch From Here Mayweather vs Mcgregor Live with 4k Display.”

In addition, the lawsuit is highly critical of efforts by the sites’ operator(s) to stuff the pages with fight-related keywords in order to draw in as much search engine traffic as they can.

“Plaintiff alleges that Defendants have engaged in such keyword stuffing as a form of search engine optimization in an effort to attract as much web traffic as possible in the form of Internet users searching for a way to access a live stream of the Fight,” it reads.

While site operators are expected to engage in such behavior, Showtime says that these SEO efforts have been particularly successful, obtaining high-ranking positions in major search engines for the would-be pirate sites.

For instance, Showtime says that a Google search for “Mayweather McGregor Live” results in four of the target websites appearing in the first 100 results, i.e the first 10 pages. Interestingly, however, to get that result searchers would need to put the search in quotes as shown above, since a plain search fails to turn anything up in hundreds of results.

At this stage, the important thing to note is that none of the sites are currently carrying links to the fight, because the fight is yet to happen. Nevertheless, Showtime is convinced that come fight night, all of the target websites will be populated with pirate links, accessible for free or after paying a fee. This needs to be stopped, it argues.

“Defendants’ anticipated unlawful distribution will impair the marketability and profitability of the Coverage, and interfere with Plaintiff’s own authorized distribution of the Coverage, because Defendants will provide consumers with an opportunity to view the Coverage in its entirety for free, rather than paying for the Coverage provided through Plaintiff’s authorized channels.

“This is especially true where, as here, the work at issue is live coverage of a one-time live sporting event whose outcome is unknown,” the network writes.

Showtime informs the court that it made efforts to contact the sites in question but had just a single response from an individual who claimed to be sports blogger who doesn’t offer streaming services. The undertone is one of disbelief.

In closing, Showtime demands a temporary restraining order, preliminary injunction, and permanent injunction, prohibiting the defendants from making the fight available in any way, and/or “forming new entities” in order to circumvent any subsequent court order. Compensation for suspected damages is also requested.

Showtime previously applied for and obtained a similar injunction to cover the (hugely disappointing) Mayweather v Pacquiao fight in 2015. In that case, websites were ordered to be taken down on the day before the fight.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

AWS Summit New York – Summary of Announcements

Post Syndicated from Jeff Barr original https://aws.amazon.com/blogs/aws/aws-summit-new-york-summary-of-announcements/

Whew – what a week! Tara, Randall, Ana, and I have been working around the clock to create blog posts for the announcements that we made at the AWS Summit in New York. Here’s a summary to help you to get started:

Amazon Macie – This new service helps you to discover, classify, and secure content at scale. Powered by machine learning and making use of Natural Language Processing (NLP), Macie looks for patterns and alerts you to suspicious behavior, and can help you with governance, compliance, and auditing. You can read Tara’s post to see how to put Macie to work; you select the buckets of interest, customize the classification settings, and review the results in the Macie Dashboard.

AWS GlueRandall’s post (with deluxe animated GIFs) introduces you to this new extract, transform, and load (ETL) service. Glue is serverless and fully managed, As you can see from the post, Glue crawls your data, infers schemas, and generates ETL scripts in Python. You define jobs that move data from place to place, with a wide selection of transforms, each expressed as code and stored in human-readable form. Glue uses Development Endpoints and notebooks to provide you with a testing environment for the scripts you build. We also announced that Amazon Athena now integrates with Amazon Glue, as does Apache Spark and Hive on Amazon EMR.

AWS Migration Hub – This new service will help you to migrate your application portfolio to AWS. My post outlines the major steps and shows you how the Migration Hub accelerates, tracks,and simplifies your migration effort. You can begin with a discovery step, or you can jump right in and migrate directly. Migration Hub integrates with tools from our migration partners and builds upon the Server Migration Service and the Database Migration Service.

CloudHSM Update – We made a major upgrade to AWS CloudHSM, making the benefits of hardware-based key management available to a wider audience. The service is offered on a pay-as-you-go basis, and is fully managed. It is open and standards compliant, with support for multiple APIs, programming languages, and cryptography extensions. CloudHSM is an integral part of AWS and can be accessed from the AWS Management Console, AWS Command Line Interface (CLI), and through API calls. Read my post to learn more and to see how to set up a CloudHSM cluster.

Managed Rules to Secure S3 Buckets – We added two new rules to AWS Config that will help you to secure your S3 buckets. The s3-bucket-public-write-prohibited rule identifies buckets that have public write access and the s3-bucket-public-read-prohibited rule identifies buckets that have global read access. As I noted in my post, you can run these rules in response to configuration changes or on a schedule. The rules make use of some leading-edge constraint solving techniques, as part of a larger effort to use automated formal reasoning about AWS.

CloudTrail for All Customers – Tara’s post revealed that AWS CloudTrail is now available and enabled by default for all AWS customers. As a bonus, Tara reviewed the principal benefits of CloudTrail and showed you how to review your event history and to deep-dive on a single event. She also showed you how to create a second trail, for use with CloudWatch CloudWatch Events.

Encryption of Data at Rest for EFS – When you create a new file system, you now have the option to select a key that will be used to encrypt the contents of the files on the file system. The encryption is done using an industry-standard AES-256 algorithm. My post shows you how to select a key and to verify that it is being used.

Watch the Keynote
My colleagues Adrian Cockcroft and Matt Wood talked about these services and others on the stage, and also invited some AWS customers to share their stories. Here’s the video:

Jeff;

 

New – AWS SAM Local (Beta) – Build and Test Serverless Applications Locally

Post Syndicated from Randall Hunt original https://aws.amazon.com/blogs/aws/new-aws-sam-local-beta-build-and-test-serverless-applications-locally/

Today we’re releasing a beta of a new tool, SAM Local, that makes it easy to build and test your serverless applications locally. In this post we’ll use SAM local to build, debug, and deploy a quick application that allows us to vote on tabs or spaces by curling an endpoint. AWS introduced Serverless Application Model (SAM) last year to make it easier for developers to deploy serverless applications. If you’re not already familiar with SAM my colleague Orr wrote a great post on how to use SAM that you can read in about 5 minutes. At it’s core, SAM is a powerful open source specification built on AWS CloudFormation that makes it easy to keep your serverless infrastructure as code – and they have the cutest mascot.

SAM Local takes all the good parts of SAM and brings them to your local machine.

There are a couple of ways to install SAM Local but the easiest is through NPM. A quick npm install -g aws-sam-local should get us going but if you want the latest version you can always install straight from the source: go get github.com/awslabs/aws-sam-local (this will create a binary named aws-sam-local, not sam).

I like to vote on things so let’s write a quick SAM application to vote on Spaces versus Tabs. We’ll use a very simple, but powerful, architecture of API Gateway fronting a Lambda function and we’ll store our results in DynamoDB. In the end a user should be able to curl our API curl https://SOMEURL/ -d '{"vote": "spaces"}' and get back the number of votes.

Let’s start by writing a simple SAM template.yaml:

AWSTemplateFormatVersion : '2010-09-09'
Transform: AWS::Serverless-2016-10-31
Resources:
  VotesTable:
    Type: "AWS::Serverless::SimpleTable"
  VoteSpacesTabs:
    Type: "AWS::Serverless::Function"
    Properties:
      Runtime: python3.6
      Handler: lambda_function.lambda_handler
      Policies: AmazonDynamoDBFullAccess
      Environment:
        Variables:
          TABLE_NAME: !Ref VotesTable
      Events:
        Vote:
          Type: Api
          Properties:
            Path: /
            Method: post

So we create a [dynamo_i] table that we expose to our Lambda function through an environment variable called TABLE_NAME.

To test that this template is valid I’ll go ahead and call sam validate to make sure I haven’t fat-fingered anything. It returns Valid! so let’s go ahead and get to work on our Lambda function.

import os
import os
import json
import boto3
votes_table = boto3.resource('dynamodb').Table(os.getenv('TABLE_NAME'))

def lambda_handler(event, context):
    print(event)
    if event['httpMethod'] == 'GET':
        resp = votes_table.scan()
        return {'body': json.dumps({item['id']: int(item['votes']) for item in resp['Items']})}
    elif event['httpMethod'] == 'POST':
        try:
            body = json.loads(event['body'])
        except:
            return {'statusCode': 400, 'body': 'malformed json input'}
        if 'vote' not in body:
            return {'statusCode': 400, 'body': 'missing vote in request body'}
        if body['vote'] not in ['spaces', 'tabs']:
            return {'statusCode': 400, 'body': 'vote value must be "spaces" or "tabs"'}

        resp = votes_table.update_item(
            Key={'id': body['vote']},
            UpdateExpression='ADD votes :incr',
            ExpressionAttributeValues={':incr': 1},
            ReturnValues='ALL_NEW'
        )
        return {'body': "{} now has {} votes".format(body['vote'], resp['Attributes']['votes'])}

So let’s test this locally. I’ll need to create a real DynamoDB database to talk to and I’ll need to provide the name of that database through the enviornment variable TABLE_NAME. I could do that with an env.json file or I can just pass it on the command line. First, I can call:
$ echo '{"httpMethod": "POST", "body": "{\"vote\": \"spaces\"}"}' |\
TABLE_NAME="vote-spaces-tabs" sam local invoke "VoteSpacesTabs"

to test the Lambda – it returns the number of votes for spaces so theoritically everything is working. Typing all of that out is a pain so I could generate a sample event with sam local generate-event api and pass that in to the local invocation. Far easier than all of that is just running our API locally. Let’s do that: sam local start-api. Now I can curl my local endpoints to test everything out.
I’ll run the command: $ curl -d '{"vote": "tabs"}' http://127.0.0.1:3000/ and it returns: “tabs now has 12 votes”. Now, of course I did not write this function perfectly on my first try. I edited and saved several times. One of the benefits of hot-reloading is that as I change the function I don’t have to do any additional work to test the new function. This makes iterative development vastly easier.

Let’s say we don’t want to deal with accessing a real DynamoDB database over the network though. What are our options? Well we can download DynamoDB Local and launch it with java -Djava.library.path=./DynamoDBLocal_lib -jar DynamoDBLocal.jar -sharedDb. Then we can have our Lambda function use the AWS_SAM_LOCAL environment variable to make some decisions about how to behave. Let’s modify our function a bit:

import os
import json
import boto3
if os.getenv("AWS_SAM_LOCAL"):
    votes_table = boto3.resource(
        'dynamodb',
        endpoint_url="http://docker.for.mac.localhost:8000/"
    ).Table("spaces-tabs-votes")
else:
    votes_table = boto3.resource('dynamodb').Table(os.getenv('TABLE_NAME'))

Now we’re using a local endpoint to connect to our local database which makes working without wifi a little easier.

SAM local even supports interactive debugging! In Java and Node.js I can just pass the -d flag and a port to immediately enable the debugger. For Python I could use a library like import epdb; epdb.serve() and connect that way. Then we can call sam local invoke -d 8080 "VoteSpacesTabs" and our function will pause execution waiting for you to step through with the debugger.

Alright, I think we’ve got everything working so let’s deploy this!

First I’ll call the sam package command which is just an alias for aws cloudformation package and then I’ll use the result of that command to sam deploy.

$ sam package --template-file template.yaml --s3-bucket MYAWESOMEBUCKET --output-template-file package.yaml
Uploading to 144e47a4a08f8338faae894afe7563c3  90570 / 90570.0  (100.00%)
Successfully packaged artifacts and wrote output template to file package.yaml.
Execute the following command to deploy the packaged template
aws cloudformation deploy --template-file package.yaml --stack-name 
$ sam deploy --template-file package.yaml --stack-name VoteForSpaces --capabilities CAPABILITY_IAM
Waiting for changeset to be created..
Waiting for stack create/update to complete
Successfully created/updated stack - VoteForSpaces

Which brings us to our API:
.

I’m going to hop over into the production stage and add some rate limiting in case you guys start voting a lot – but otherwise we’ve taken our local work and deployed it to the cloud without much effort at all. I always enjoy it when things work on the first deploy!

You can vote now and watch the results live! http://spaces-or-tabs.s3-website-us-east-1.amazonaws.com/

We hope that SAM Local makes it easier for you to test, debug, and deploy your serverless apps. We have a CONTRIBUTING.md guide and we welcome pull requests. Please tweet at us to let us know what cool things you build. You can see our What’s New post here and the documentation is live here.

Randall

Turbocharge your Apache Hive queries on Amazon EMR using LLAP

Post Syndicated from Jigar Mistry original https://aws.amazon.com/blogs/big-data/turbocharge-your-apache-hive-queries-on-amazon-emr-using-llap/

Apache Hive is one of the most popular tools for analyzing large datasets stored in a Hadoop cluster using SQL. Data analysts and scientists use Hive to query, summarize, explore, and analyze big data.

With the introduction of Hive LLAP (Low Latency Analytical Processing), the notion of Hive being just a batch processing tool has changed. LLAP uses long-lived daemons with intelligent in-memory caching to circumvent batch-oriented latency and provide sub-second query response times.

This post provides an overview of Hive LLAP, including its architecture and common use cases for boosting query performance. You will learn how to install and configure Hive LLAP on an Amazon EMR cluster and run queries on LLAP daemons.

What is Hive LLAP?

Hive LLAP was introduced in Apache Hive 2.0, which provides very fast processing of queries. It uses persistent daemons that are deployed on a Hadoop YARN cluster using Apache Slider. These daemons are long-running and provide functionality such as I/O with DataNode, in-memory caching, query processing, and fine-grained access control. And since the daemons are always running in the cluster, it saves substantial overhead of launching new YARN containers for every new Hive session, thereby avoiding long startup times.

When Hive is configured in hybrid execution mode, small and short queries execute directly on LLAP daemons. Heavy lifting (like large shuffles in the reduce stage) is performed in YARN containers that belong to the application. Resources (CPU, memory, etc.) are obtained in a traditional fashion using YARN. After the resources are obtained, the execution engine can decide which resources are to be allocated to LLAP, or it can launch Apache Tez processors in separate YARN containers. You can also configure Hive to run all the processing workloads on LLAP daemons for querying small datasets at lightning fast speeds.

LLAP daemons are launched under YARN management to ensure that the nodes don’t get overloaded with the compute resources of these daemons. You can use scheduling queues to make sure that there is enough compute capacity for other YARN applications to run.

Why use Hive LLAP?

With many options available in the market (Presto, Spark SQL, etc.) for doing interactive SQL  over data that is stored in Amazon S3 and HDFS, there are several reasons why using Hive and LLAP might be a good choice:

  • For those who are heavily invested in the Hive ecosystem and have external BI tools that connect to Hive over JDBC/ODBC connections, LLAP plugs in to their existing architecture without a steep learning curve.
  • It’s compatible with existing Hive SQL and other Hive tools, like HiveServer2, and JDBC drivers for Hive.
  • It has native support for security features with authentication and authorization (SQL standards-based authorization) using HiveServer2.
  • LLAP daemons are aware about of the columns and records that are being processed which enables you to enforce fine-grained access control.
  • It can use Hive’s vectorization capabilities to speed up queries, and Hive has better support for Parquet file format when vectorization is enabled.
  • It can take advantage of a number of Hive optimizations like merging multiple small files for query results, automatically determining the number of reducers for joins and groupbys, etc.
  • It’s optional and modular so it can be turned on or off depending on the compute and resource requirements of the cluster. This lets you to run other YARN applications concurrently without reserving a cluster specifically for LLAP.

How do you install Hive LLAP in Amazon EMR?

To install and configure LLAP on an EMR cluster, use the following bootstrap action (BA):

s3://aws-bigdata-blog/artifacts/Turbocharge_Apache_Hive_on_EMR/configure-Hive-LLAP.sh

This BA downloads and installs Apache Slider on the cluster and configures LLAP so that it works with EMR Hive. For LLAP to work, the EMR cluster must have Hive, Tez, and Apache Zookeeper installed.

You can pass the following arguments to the BA.

Argument Definition Default value
--instances Number of instances of LLAP daemon Number of core/task nodes of the cluster
--cache Cache size per instance 20% of physical memory of the node
--executors Number of executors per instance Number of CPU cores of the node
--iothreads Number of IO threads per instance Number of CPU cores of the node
--size Container size per instance 50% of physical memory of the node
--xmx Working memory size 50% of container size
--log-level Log levels for the LLAP instance INFO

LLAP example

This section describes how you can try the faster Hive queries with LLAP using the TPC-DS testbench for Hive on Amazon EMR.

Use the following AWS command line interface (AWS CLI) command to launch a 1+3 nodes m4.xlarge EMR 5.6.0 cluster with the bootstrap action to install LLAP:

aws emr create-cluster --release-label emr-5.6.0 \
--applications Name=Hadoop Name=Hive Name=Hue Name=ZooKeeper Name=Tez \
--bootstrap-actions '[{"Path":"s3://aws-bigdata-blog/artifacts/Turbocharge_Apache_Hive_on_EMR/configure-Hive-LLAP.sh","Name":"Custom action"}]' \ 
--ec2-attributes '{"KeyName":"<YOUR-KEY-PAIR>","InstanceProfile":"EMR_EC2_DefaultRole","SubnetId":"subnet-xxxxxxxx","EmrManagedSlaveSecurityGroup":"sg-xxxxxxxx","EmrManagedMasterSecurityGroup":"sg-xxxxxxxx"}' 
--service-role EMR_DefaultRole \
--enable-debugging \
--log-uri 's3n://<YOUR-BUCKET/' --name 'test-hive-llap' \
--instance-groups '[{"InstanceCount":1,"EbsConfiguration":{"EbsBlockDeviceConfigs":[{"VolumeSpecification":{"SizeInGB":32,"VolumeType":"gp2"},"VolumesPerInstance":1}],"EbsOptimized":true},"InstanceGroupType":"MASTER","InstanceType":"m4.xlarge","Name":"Master - 1"},{"InstanceCount":3,"EbsConfiguration":{"EbsBlockDeviceConfigs":[{"VolumeSpecification":{"SizeInGB":32,"VolumeType":"gp2"},"VolumesPerInstance":1}],"EbsOptimized":true},"InstanceGroupType":"CORE","InstanceType":"m4.xlarge","Name":"Core - 2"}]' 
--region us-east-1

After the cluster is launched, log in to the master node using SSH, and do the following:

  1. Open the hive-tpcds folder:
    cd /home/hadoop/hive-tpcds/
  2. Start Hive CLI using the testbench configuration, create the required tables, and run the sample query:

    hive –i testbench.settings
    hive> source create_tables.sql;
    hive> source query55.sql;

    This sample query runs on a 40 GB dataset that is stored on Amazon S3. The dataset is generated using the data generation tool in the TPC-DS testbench for Hive.It results in output like the following:
  3. This screenshot shows that the query finished in about 47 seconds for LLAP mode. Now, to compare this to the execution time without LLAP, you can run the same workload using only Tez containers:
    hive> set hive.llap.execution.mode=none;
    hive> source query55.sql;


    This query finished in about 80 seconds.

The difference in query execution time is almost 1.7 times when using just YARN containers in contrast to running the query on LLAP daemons. And with every rerun of the query, you notice that the execution time substantially decreases by the virtue of in-memory caching by LLAP daemons.

Conclusion

In this post, I introduced Hive LLAP as a way to boost Hive query performance. I discussed its architecture and described several use cases for the component. I showed how you can install and configure Hive LLAP on an Amazon EMR cluster and how you can run queries on LLAP daemons.

If you have questions about using Hive LLAP on Amazon EMR or would like to share your use cases, please leave a comment below.


Additional Reading

Learn how to to automatically partition Hive external tables with AWS.


About the Author

Jigar Mistry is a Hadoop Systems Engineer with Amazon Web Services. He works with customers to provide them architectural guidance and technical support for processing large datasets in the cloud using open-source applications. In his spare time, he enjoys going for camping and exploring different restaurants in the Seattle area.

 

 

 

 

Updates to GPIO Zero, the physical computing API

Post Syndicated from Ben Nuttall original https://www.raspberrypi.org/blog/gpio-zero-update/

GPIO Zero v1.4 is out now! It comes with a set of new features, including a handy pinout command line tool. To start using this newest version of the API, update your Raspbian OS now:

sudo apt update && sudo apt upgrade

Some of the things we’ve added will make it easier for you try your hand on different programming styles. In doing so you’ll build your coding skills, and will improve as a programmer. As a consequence, you’ll learn to write more complex code, which will enable you to take on advanced electronics builds. And on top of that, you can use the skills you’ll acquire in other computing projects.

GPIO Zero pinout tool

The new pinout tool

Developing GPIO Zero

Nearly two years ago, I started the GPIO Zero project as a simple wrapper around the low-level RPi.GPIO library. I wanted to create a simpler way to control GPIO-connected devices in Python, based on three years’ experience of training teachers, running workshops, and building projects. The idea grew over time, and the more we built for our Python library, the more sophisticated and powerful it became.

One of the great things about Python is that it’s a multi-paradigm programming language. You can write code in a number of different styles, according to your needs. You don’t have to write classes, but you can if you need them. There are functional programming tools available, but beginners get by without them. Importantly, the more advanced features of the language are not a barrier to entry.

Become a more advanced programmer

As a beginner to programming, you usually start by writing procedural programs, in which the flow moves from top to bottom. Then you’ll probably add loops and create your own functions. Your next step might be to start using libraries which introduce new patterns that operate in a different manner to what you’ve written before, for example threaded callbacks (event-driven programming). You might move on to object-oriented programming, extending the functionality of classes provided by other libraries, and starting to write your own classes. Occasionally, you may make use of tools created with functional programming techniques.

Five buttons in different colours

Take control of the buttons in your life

It’s much the same with GPIO Zero: you can start using it very easily, and we’ve made it simple to progress along the learning curve towards more advanced programming techniques. For example, if you want to make a push button control an LED, the easiest way to do this is via procedural programming using a while loop:

from gpiozero import LED, Button

led = LED(17)
button = Button(2)

while True:
    if button.is_pressed:
        led.on()
    else:
        led.off()

But another way to achieve the same thing is to use events:

from gpiozero import LED, Button
from signal import pause

led = LED(17)
button = Button(2)

button.when_pressed = led.on
button.when_released = led.off

pause()

You could even use a declarative approach, and set the LED’s behaviour in a single line:

from gpiozero import LED, Button
from signal import pause

led = LED(17)
button = Button(2)

led.source = button.values

pause()

You will find that using the procedural approach is a great start, but at some point you’ll hit a limit, and will have to try a different approach. The example above can be approach in several programming styles. However, if you’d like to control a wider range of devices or a more complex system, you need to carefully consider which style works best for what you want to achieve. Being able to choose the right programming style for a task is a skill in itself.

Source/values properties

So how does the led.source = button.values thing actually work?

Every GPIO Zero device has a .value property. For example, you can read a button’s state (True or False), and read or set an LED’s state (so led.value = True is the same as led.on()). Since LEDs and buttons operate with the same value set (True and False), you could say led.value = button.value. However, this only sets the LED to match the button once. If you wanted it to always match the button’s state, you’d have to use a while loop. To make things easier, we came up with a way of telling devices they’re connected: we added a .values property to all devices, and a .source to output devices. Now, a loop is no longer necessary, because this will do the job:

led.source = button.values

This is a simple approach to connecting devices using a declarative style of programming. In one single line, we declare that the LED should get its values from the button, i.e. when the button is pressed, the LED should be on. You can even mix the procedural with the declarative style: at one stage of the program, the LED could be set to match the button, while in the next stage it could just be blinking, and finally it might return back to its original state.

These additions are useful for connecting other devices as well. For example, a PWMLED (LED with variable brightness) has a value between 0 and 1, and so does a potentiometer connected via an ADC (analogue-digital converter) such as the MCP3008. The new GPIO Zero update allows you to say led.source = pot.values, and then twist the potentiometer to control the brightness of the LED.

But what if you want to do something more complex, like connect two devices with different value sets or combine multiple inputs?

We provide a set of device source tools, which allow you to process values as they flow from one device to another. They also let you send in artificial values such as random data, and you can even write your own functions to generate values to pass to a device’s source. For example, to control a motor’s speed with a potentiometer, you could use this code:

from gpiozero import Motor, MCP3008
from signal import pause

motor = Motor(20, 21)
pot = MCP3008()

motor.source = pot.values

pause()

This works, but it will only drive the motor forwards. If you wanted the potentiometer to drive it forwards and backwards, you’d use the scaled tool to scale its values to a range of -1 to 1:

from gpiozero import Motor, MCP3008
from gpiozero.tools import scaled
from signal import pause

motor = Motor(20, 21)
pot = MCP3008()

motor.source = scaled(pot.values, -1, 1)

pause()

And to separately control a robot’s left and right motor speeds with two potentiometers, you could do this:

from gpiozero import Robot, MCP3008
from signal import pause

robot = Robot(left=(2, 3), right=(4, 5))
left = MCP3008(0)
right = MCP3008(1)

robot.source = zip(left.values, right.values)

pause()

GPIO Zero and Blue Dot

Martin O’Hanlon created a Python library called Blue Dot which allows you to use your Android device to remotely control things on their Raspberry Pi. The API is very similar to GPIO Zero, and it even incorporates the value/values properties, which means you can hook it up to GPIO devices easily:

from bluedot import BlueDot
from gpiozero import LED
from signal import pause

bd = BlueDot()
led = LED(17)

led.source = bd.values

pause()

We even included a couple of Blue Dot examples in our recipes.

Make a series of binary logic gates using source/values

Read more in this source/values tutorial from The MagPi, and on the source/values documentation page.

Remote GPIO control

GPIO Zero supports multiple low-level GPIO libraries. We use RPi.GPIO by default, but you can choose to use RPIO or pigpio instead. The pigpio library supports remote connections, so you can run GPIO Zero on one Raspberry Pi to control the GPIO pins of another, or run code on a PC (running Windows, Mac, or Linux) to remotely control the pins of a Pi on the same network. You can even control two or more Pis at once!

If you’re using Raspbian on a Raspberry Pi (or a PC running our x86 Raspbian OS), you have everything you need to remotely control GPIO. If you’re on a PC running Windows, Mac, or Linux, you just need to install gpiozero and pigpio using pip. See our guide on configuring remote GPIO.

I road-tested the new pin_factory syntax at the Raspberry Jam @ Pi Towers

There are a number of different ways to use remote pins:

  • Set the default pin factory and remote IP address with environment variables:
$ GPIOZERO_PIN_FACTORY=pigpio PIGPIO_ADDR=192.168.1.2 python3 blink.py
  • Set the default pin factory in your script:
import gpiozero
from gpiozero import LED
from gpiozero.pins.pigpio import PiGPIOFactory

gpiozero.Device.pin_factory = PiGPIOFactory(host='192.168.1.2')

led = LED(17)
  • The pin_factory keyword argument allows you to use multiple Pis in the same script:
from gpiozero import LED
from gpiozero.pins.pigpio import PiGPIOFactory

factory2 = PiGPIOFactory(host='192.168.1.2')
factory3 = PiGPIOFactory(host='192.168.1.3')

local_hat = TrafficHat()
remote_hat2 = TrafficHat(pin_factory=factory2)
remote_hat3 = TrafficHat(pin_factory=factory3)

This is a really powerful feature! For more, read this remote GPIO tutorial in The MagPi, and check out the remote GPIO recipes in our documentation.

GPIO Zero on your PC

GPIO Zero doesn’t have any dependencies, so you can install it on your PC using pip. In addition to the API’s remote GPIO control, you can use its ‘mock’ pin factory on your PC. We originally created the mock pin feature for the GPIO Zero test suite, but we found that it’s really useful to be able to test GPIO Zero code works without running it on real hardware:

$ GPIOZERO_PIN_FACTORY=mock python3
>>> from gpiozero import LED
>>> led = LED(22)
>>> led.blink()
>>> led.value
True
>>> led.value
False

You can even tell pins to change state (e.g. to simulate a button being pressed) by accessing an object’s pin property:

>>> from gpiozero import LED
>>> led = LED(22)
>>> button = Button(23)
>>> led.source = button.values
>>> led.value
False
>>> button.pin.drive_low()
>>> led.value
True

You can also use the pinout command line tool if you set your pin factory to ‘mock’. It gives you a Pi 3 diagram by default, but you can supply a revision code to see information about other Pi models. For example, to use the pinout tool for the original 256MB Model B, just type pinout -r 2.

GPIO Zero documentation and resources

On the API’s website, we provide beginner recipes and advanced recipes, and we have added remote GPIO configuration including PC/Mac/Linux and Pi Zero OTG, and a section of GPIO recipes. There are also new sections on source/values, command-line tools, FAQs, Pi information and library development.

You’ll find plenty of cool projects using GPIO Zero in our learning resources. For example, you could check out the one that introduces physical computing with Python and get stuck in! We even provide a GPIO Zero cheat sheet you can download and print.

There are great GPIO Zero tutorials and projects in The MagPi magazine every month. Moreover, they also publish Simple Electronics with GPIO Zero, a book which collects a series of tutorials useful for building your knowledge of physical computing. And the best thing is, you can download it, and all magazine issues, for free!

Check out the API documentation and read more about what’s new in GPIO Zero on my blog. We have lots planned for the next release. Watch this space.

Get building!

The world of physical computing is at your fingertips! Are you feeling inspired?

If you’ve never tried your hand on physical computing, our Build a robot buggy learning resource is the perfect place to start! It’s your step-by-step guide for building a simple robot controlled with the help of GPIO Zero.

If you have a gee-whizz idea for an electronics project, do share it with us below. And if you’re currently working on a cool build and would like to show us how it’s going, pop a link to it in the comments.

The post Updates to GPIO Zero, the physical computing API appeared first on Raspberry Pi.

Top 10 Most Obvious Hacks of All Time (v0.9)

Post Syndicated from Robert Graham original http://blog.erratasec.com/2017/07/top-10-most-obvious-hacks-of-all-time.html

For teaching hacking/cybersecurity, I thought I’d create of the most obvious hacks of all time. Not the best hacks, the most sophisticated hacks, or the hacks with the biggest impact, but the most obvious hacks — ones that even the least knowledgeable among us should be able to understand. Below I propose some hacks that fit this bill, though in no particular order.

The reason I’m writing this is that my niece wants me to teach her some hacking. I thought I’d start with the obvious stuff first.

Shared Passwords

If you use the same password for every website, and one of those websites gets hacked, then the hacker has your password for all your websites. The reason your Facebook account got hacked wasn’t because of anything Facebook did, but because you used the same email-address and password when creating an account on “beagleforums.com”, which got hacked last year.

I’ve heard people say “I’m sure, because I choose a complex password and use it everywhere”. No, this is the very worst thing you can do. Sure, you can the use the same password on all sites you don’t care much about, but for Facebook, your email account, and your bank, you should have a unique password, so that when other sites get hacked, your important sites are secure.

And yes, it’s okay to write down your passwords on paper.

Tools: HaveIBeenPwned.com

PIN encrypted PDFs

My accountant emails PDF statements encrypted with the last 4 digits of my Social Security Number. This is not encryption — a 4 digit number has only 10,000 combinations, and a hacker can guess all of them in seconds.
PIN numbers for ATM cards work because ATM machines are online, and the machine can reject your card after four guesses. PIN numbers don’t work for documents, because they are offline — the hacker has a copy of the document on their own machine, disconnected from the Internet, and can continue making bad guesses with no restrictions.
Passwords protecting documents must be long enough that even trillion upon trillion guesses are insufficient to guess.

Tools: Hashcat, John the Ripper

SQL and other injection

The lazy way of combining websites with databases is to combine user input with an SQL statement. This combines code with data, so the obvious consequence is that hackers can craft data to mess with the code.
No, this isn’t obvious to the general public, but it should be obvious to programmers. The moment you write code that adds unfiltered user-input to an SQL statement, the consequence should be obvious. Yet, “SQL injection” has remained one of the most effective hacks for the last 15 years because somehow programmers don’t understand the consequence.
CGI shell injection is a similar issue. Back in early days, when “CGI scripts” were a thing, it was really important, but these days, not so much, so I just included it with SQL. The consequence of executing shell code should’ve been obvious, but weirdly, it wasn’t. The IT guy at the company I worked for back in the late 1990s came to me and asked “this guy says we have a vulnerability, is he full of shit?”, and I had to answer “no, he’s right — obviously so”.

XSS (“Cross Site Scripting”) [*] is another injection issue, but this time at somebody’s web browser rather than a server. It works because websites will echo back what is sent to them. For example, if you search for Cross Site Scripting with the URL https://www.google.com/search?q=cross+site+scripting, then you’ll get a page back from the server that contains that string. If the string is JavaScript code rather than text, then some servers (thought not Google) send back the code in the page in a way that it’ll be executed. This is most often used to hack somebody’s account: you send them an email or tweet a link, and when they click on it, the JavaScript gives control of the account to the hacker.

Cross site injection issues like this should probably be their own category, but I’m including it here for now.

More: Wikipedia on SQL injection, Wikipedia on cross site scripting.
Tools: Burpsuite, SQLmap

Buffer overflows

In the C programming language, programmers first create a buffer, then read input into it. If input is long than the buffer, then it overflows. The extra bytes overwrite other parts of the program, letting the hacker run code.
Again, it’s not a thing the general public is expected to know about, but is instead something C programmers should be expected to understand. They should know that it’s up to them to check the length and stop reading input before it overflows the buffer, that there’s no language feature that takes care of this for them.
We are three decades after the first major buffer overflow exploits, so there is no excuse for C programmers not to understand this issue.

What makes particular obvious is the way they are wrapped in exploits, like in Metasploit. While the bug itself is obvious that it’s a bug, actually exploiting it can take some very non-obvious skill. However, once that exploit is written, any trained monkey can press a button and run the exploit. That’s where we get the insult “script kiddie” from — referring to wannabe-hackers who never learn enough to write their own exploits, but who spend a lot of time running the exploit scripts written by better hackers than they.

More: Wikipedia on buffer overflow, Wikipedia on script kiddie,  “Smashing The Stack For Fun And Profit” — Phrack (1996)
Tools: bash, Metasploit

SendMail DEBUG command (historical)

The first popular email server in the 1980s was called “SendMail”. It had a feature whereby if you send a “DEBUG” command to it, it would execute any code following the command. The consequence of this was obvious — hackers could (and did) upload code to take control of the server. This was used in the Morris Worm of 1988. Most Internet machines of the day ran SendMail, so the worm spread fast infecting most machines.
This bug was mostly ignored at the time. It was thought of as a theoretical problem, that might only rarely be used to hack a system. Part of the motivation of the Morris Worm was to demonstrate that such problems was to demonstrate the consequences — consequences that should’ve been obvious but somehow were rejected by everyone.

More: Wikipedia on Morris Worm

Email Attachments/Links

I’m conflicted whether I should add this or not, because here’s the deal: you are supposed to click on attachments and links within emails. That’s what they are there for. The difference between good and bad attachments/links is not obvious. Indeed, easy-to-use email systems makes detecting the difference harder.
On the other hand, the consequences of bad attachments/links is obvious. That worms like ILOVEYOU spread so easily is because people trusted attachments coming from their friends, and ran them.
We have no solution to the problem of bad email attachments and links. Viruses and phishing are pervasive problems. Yet, we know why they exist.

Default and backdoor passwords

The Mirai botnet was caused by surveillance-cameras having default and backdoor passwords, and being exposed to the Internet without a firewall. The consequence should be obvious: people will discover the passwords and use them to take control of the bots.
Surveillance-cameras have the problem that they are usually exposed to the public, and can’t be reached without a ladder — often a really tall ladder. Therefore, you don’t want a button consumers can press to reset to factory defaults. You want a remote way to reset them. Therefore, they put backdoor passwords to do the reset. Such passwords are easy for hackers to reverse-engineer, and hence, take control of millions of cameras across the Internet.
The same reasoning applies to “default” passwords. Many users will not change the defaults, leaving a ton of devices hackers can hack.

Masscan and background radiation of the Internet

I’ve written a tool that can easily scan the entire Internet in a short period of time. It surprises people that this possible, but it obvious from the numbers. Internet addresses are only 32-bits long, or roughly 4 billion combinations. A fast Internet link can easily handle 1 million packets-per-second, so the entire Internet can be scanned in 4000 seconds, little more than an hour. It’s basic math.
Because it’s so easy, many people do it. If you monitor your Internet link, you’ll see a steady trickle of packets coming in from all over the Internet, especially Russia and China, from hackers scanning the Internet for things they can hack.
People’s reaction to this scanning is weirdly emotional, taking is personally, such as:
  1. Why are they hacking me? What did I do to them?
  2. Great! They are hacking me! That must mean I’m important!
  3. Grrr! How dare they?! How can I hack them back for some retribution!?

I find this odd, because obviously such scanning isn’t personal, the hackers have no idea who you are.

Tools: masscan, firewalls

Packet-sniffing, sidejacking

If you connect to the Starbucks WiFi, a hacker nearby can easily eavesdrop on your network traffic, because it’s not encrypted. Windows even warns you about this, in case you weren’t sure.

At DefCon, they have a “Wall of Sheep”, where they show passwords from people who logged onto stuff using the insecure “DefCon-Open” network. Calling them “sheep” for not grasping this basic fact that unencrypted traffic is unencrypted.

To be fair, it’s actually non-obvious to many people. Even if the WiFi itself is not encrypted, SSL traffic is. They expect their services to be encrypted, without them having to worry about it. And in fact, most are, especially Google, Facebook, Twitter, Apple, and other major services that won’t allow you to log in anymore without encryption.

But many services (especially old ones) may not be encrypted. Unless users check and verify them carefully, they’ll happily expose passwords.

What’s interesting about this was 10 years ago, when most services which only used SSL to encrypt the passwords, but then used unencrypted connections after that, using “cookies”. This allowed the cookies to be sniffed and stolen, allowing other people to share the login session. I used this on stage at BlackHat to connect to somebody’s GMail session. Google, and other major websites, fixed this soon after. But it should never have been a problem — because the sidejacking of cookies should have been obvious.

Tools: Wireshark, dsniff

Stuxnet LNK vulnerability

Again, this issue isn’t obvious to the public, but it should’ve been obvious to anybody who knew how Windows works.
When Windows loads a .dll, it first calls the function DllMain(). A Windows link file (.lnk) can load icons/graphics from the resources in a .dll file. It does this by loading the .dll file, thus calling DllMain. Thus, a hacker could put on a USB drive a .lnk file pointing to a .dll file, and thus, cause arbitrary code execution as soon as a user inserted a drive.
I say this is obvious because I did this, created .lnks that pointed to .dlls, but without hostile DllMain code. The consequence should’ve been obvious to me, but I totally missed the connection. We all missed the connection, for decades.

Social Engineering and Tech Support [* * *]

After posting this, many people have pointed out “social engineering”, especially of “tech support”. This probably should be up near #1 in terms of obviousness.

The classic example of social engineering is when you call tech support and tell them you’ve lost your password, and they reset it for you with minimum of questions proving who you are. For example, you set the volume on your computer really loud and play the sound of a crying baby in the background and appear to be a bit frazzled and incoherent, which explains why you aren’t answering the questions they are asking. They, understanding your predicament as a new parent, will go the extra mile in helping you, resetting “your” password.

One of the interesting consequences is how it affects domain names (DNS). It’s quite easy in many cases to call up the registrar and convince them to transfer a domain name. This has been used in lots of hacks. It’s really hard to defend against. If a registrar charges only $9/year for a domain name, then it really can’t afford to provide very good tech support — or very secure tech support — to prevent this sort of hack.

Social engineering is such a huge problem, and obvious problem, that it’s outside the scope of this document. Just google it to find example after example.

A related issue that perhaps deserves it’s own section is OSINT [*], or “open-source intelligence”, where you gather public information about a target. For example, on the day the bank manager is out on vacation (which you got from their Facebook post) you show up and claim to be a bank auditor, and are shown into their office where you grab their backup tapes. (We’ve actually done this).

More: Wikipedia on Social Engineering, Wikipedia on OSINT, “How I Won the Defcon Social Engineering CTF” — blogpost (2011), “Questioning 42: Where’s the Engineering in Social Engineering of Namespace Compromises” — BSidesLV talk (2016)

Blue-boxes (historical) [*]

Telephones historically used what we call “in-band signaling”. That’s why when you dial on an old phone, it makes sounds — those sounds are sent no differently than the way your voice is sent. Thus, it was possible to make tone generators to do things other than simply dial calls. Early hackers (in the 1970s) would make tone-generators called “blue-boxes” and “black-boxes” to make free long distance calls, for example.

These days, “signaling” and “voice” are digitized, then sent as separate channels or “bands”. This is call “out-of-band signaling”. You can’t trick the phone system by generating tones. When your iPhone makes sounds when you dial, it’s entirely for you benefit and has nothing to do with how it signals the cell tower to make a call.

Early hackers, like the founders of Apple, are famous for having started their careers making such “boxes” for tricking the phone system. The problem was obvious back in the day, which is why as the phone system moves from analog to digital, the problem was fixed.

More: Wikipedia on blue box, Wikipedia article on Steve Wozniak.

Thumb drives in parking lots [*]

A simple trick is to put a virus on a USB flash drive, and drop it in a parking lot. Somebody is bound to notice it, stick it in their computer, and open the file.

This can be extended with tricks. For example, you can put a file labeled “third-quarter-salaries.xlsx” on the drive that required macros to be run in order to open. It’s irresistible to other employees who want to know what their peers are being paid, so they’ll bypass any warning prompts in order to see the data.

Another example is to go online and get custom USB sticks made printed with the logo of the target company, making them seem more trustworthy.

We also did a trick of taking an Adobe Flash game “Punch the Monkey” and replaced the monkey with a logo of a competitor of our target. They now only played the game (infecting themselves with our virus), but gave to others inside the company to play, infecting others, including the CEO.

Thumb drives like this have been used in many incidents, such as Russians hacking military headquarters in Afghanistan. It’s really hard to defend against.

More: “Computer Virus Hits U.S. Military Base in Afghanistan” — USNews (2008), “The Return of the Worm That Ate The Pentagon” — Wired (2011), DoD Bans Flash Drives — Stripes (2008)

Googling [*]

Search engines like Google will index your website — your entire website. Frequently companies put things on their website without much protection because they are nearly impossible for users to find. But Google finds them, then indexes them, causing them to pop up with innocent searches.
There are books written on “Google hacking” explaining what search terms to look for, like “not for public release”, in order to find such documents.

More: Wikipedia entry on Google Hacking, “Google Hacking” book.

URL editing [*]

At the top of every browser is what’s called the “URL”. You can change it. Thus, if you see a URL that looks like this:

http://www.example.com/documents?id=138493

Then you can edit it to see the next document on the server:

http://www.example.com/documents?id=138494

The owner of the website may think they are secure, because nothing points to this document, so the Google search won’t find it. But that doesn’t stop a user from manually editing the URL.
An example of this is a big Fortune 500 company that posts the quarterly results to the website an hour before the official announcement. Simply editing the URL from previous financial announcements allows hackers to find the document, then buy/sell the stock as appropriate in order to make a lot of money.
Another example is the classic case of Andrew “Weev” Auernheimer who did this trick in order to download the account email addresses of early owners of the iPad, including movie stars and members of the Obama administration. It’s an interesting legal case because on one hand, techies consider this so obvious as to not be “hacking”. On the other hand, non-techies, especially judges and prosecutors, believe this to be obviously “hacking”.

DDoS, spoofing, and amplification [*]

For decades now, online gamers have figured out an easy way to win: just flood the opponent with Internet traffic, slowing their network connection. This is called a DoS, which stands for “Denial of Service”. DoSing game competitors is often a teenager’s first foray into hacking.
A variant of this is when you hack a bunch of other machines on the Internet, then command them to flood your target. (The hacked machines are often called a “botnet”, a network of robot computers). This is called DDoS, or “Distributed DoS”. At this point, it gets quite serious, as instead of competitive gamers hackers can take down entire businesses. Extortion scams, DDoSing websites then demanding payment to stop, is a common way hackers earn money.
Another form of DDoS is “amplification”. Sometimes when you send a packet to a machine on the Internet it’ll respond with a much larger response, either a very large packet or many packets. The hacker can then send a packet to many of these sites, “spoofing” or forging the IP address of the victim. This causes all those sites to then flood the victim with traffic. Thus, with a small amount of outbound traffic, the hacker can flood the inbound traffic of the victim.
This is one of those things that has worked for 20 years, because it’s so obvious teenagers can do it, yet there is no obvious solution. President Trump’s executive order of cyberspace specifically demanded that his government come up with a report on how to address this, but it’s unlikely that they’ll come up with any useful strategy.

More: Wikipedia on DDoS, Wikipedia on Spoofing

Conclusion

Tweet me (@ErrataRob) your obvious hacks, so I can add them to the list.

Ethereum, Proof-of-Stake… and the consequences

Post Syndicated from Григор original http://www.gatchev.info/blog/?p=2070

For those who have been living the last few years in a cave without Internet: Ethereum is a cryptocurrency project, based around the coin Ether. It has the support of many big banks, big hedge funds and some states (Russia, China etc). Among the cryptocurrencies, it is second only to Bitcoin – and might even overtake it with the time. (Especially if Bitcoin doesn’t finally move and fix some of its problems.)

Ethereum offers some abilities that few other cryptocurrencies do. The most important one is the support for “smart projects” – kind of electronic contracts that can easily be executed and enforced with little to no human participation. This post however is dedicated to another of its traits – the Proof of Stake.

To work and exist, every cryptocurrency depends on some proof. Most of them use Proof-of-Work scheme. In it, one has to put some work – eg. calculating checksums – behind its participation in the network and its decision, and receive newly generated coins for it. This however results in huge amount of work done only to prove that, well, you can do it and deserve to be in and receive some of the newly squeezed juice.

As of August 2017, Ethereum uses this scheme too. However, they plan to switch to a Proof-of-Stake algorithm named Casper. In it, you prove yourself not by doing work, but by proving to own Ether. As this requires practically no work, it is much more technically effective than the Proof-of-Work schemes.

Technically, Caspar is an amazing design. I congratulate the Ethereum team for it. However, economically its usage appears to have an important weakness. It is described below.

—-

A polarized system

With Casper, the Ether generated by the Ethereum network and the decision power in it are distributed to these who already own Ether. As a consequence, most of both go to those who own most Ether. (There might be attempts to limit that, but these are easily defeatable. For example, limiting the amount distributed to an address can be circumvented by a Sybil attack.)

Such a distribution will create with the time a financial ecosystem where most money and vote are held by a small minority of the participants. The big majority will have little to no of both – it will summarily hold less money and vote than the minority of “haves”. Giving the speed with which the cryptocurrency systems evolve, it is realistic to expect this development in ten, maybe even in five or less years after introducing Casper.

The “middle class”

Economists love to repeat how important is to have a strong middle class. Why, and how that translates to the situation in a cryptocurrency-based financial system?

In systemic terms, “middle class” denotes in a financial system the set of entities that control each a noticeable but not very big amount of resources.

Game theory shows that in a financial system, entities with different clout usually have different interests. These interests usually reflect the amount of resources they control. Entities with little to no resources tend to have interests opposing to these with biggest resources – especially in systems where the total amount of resources changes slowly and the economics is close to a zero-sum game. (For example, in most cryptocurrency systems.) The “middle class” entities interests in most aspects are in the middle.

For an economics to work, there must be a balance of interests that creates incentive for all of its members to participate. In financial systems, where “haves” interests are mostly opposing to “have-nots” interests, creating such a balance depends on the presence and influence of a “middle class”. Its interests are usually the closest to a compromise that satisfies all, and its influence is the key to achieving that compromise within the system.

If the system state is not acceptable for all entities, these who do not accept it eventually leave. (Usually their participation is required for the system survival, so this brings the system down.) If these entities cannot leave the system, they ultimately reject its rules and try to change it by force. If that is impossible too, they usually resort to denying the system what makes them useful for it, thus decreasing its competitiveness to other systems.

The most reliable way to have acceptable compromise enforced in a system is to have in it a “middle class” that summarily controls more resources than any other segment of entities, preferably at least 51% of the system resources. (This assumes that the “middle class” is able and willing to protect their interests. If some of these entities are controlled into defending someone else’s interests – eg. botnets in computer networks, manipulated voters during elections, etc – these numbers apply to the non-controlled among them.)

A system that doesn’t have a non-controlled “middle class” that controls a decisive amount of resources, usually does not have an influential set of interests that are an acceptable compromise between the interests poles. For this reason, it can be called a polarized system.

The limitation on development

In a polarized system, the incentive for development is minimized. (Development is potentially disruptive, and the majority of the financial abilities and the decision power there has only to lose from a disruption. When factoring in the expected profits from development, the situation always becomes a zero-sum game.) The system becomes static (thus cementing the zero-sum game situation in it) and is under threat of being overtaken by a competing financial system. When that happens, it is usually destroyed with all stakes in it.

Also, almost any initiative in such a financial system is bound to turn into a cartel, oligopoly or monopoly, due to the small number of participants with resources to start and support an initiative. That effectively destroys its markets, contributing to the weakness of the system and limiting further its ability to develop.

Another problem that stems from this is that the incentive during an interaction to violate the rules and to push the contragent into a loss is greater than the incentive to compete by giving a better offer. This in turn removes the incentive to increase productivity, which is a key incentive for development.)

Yet another problem of the concentration of most resources into few entities is the increased gain from attacking one of them and appropriating their resources, and thus the incentive to do it. Since good defensive capabilities are usually an excellent offense base, this pulls the “haves” into an “arms race”, redirecting more and more of their resources into defense. This also leaves the development outside the arms race increasingly resource-strapped. (The “arms race” itself generates development, but the race situation prevents that into trickling into “non-military” applications.)

These are only a part of the constraints on development in a polarized system. Listing all of them will make a long read.

Trickle-up and trickle-down

In theory, every economical system involves two processes: trickle-down and trickle-up. So, any concentration of resources on the top should be decreased by an automatically increased trickle-down. However, a better understanding how these processes work shows that this logic is faulty.

Any financial exchange in a system consists of two parts. One of them covers the actual production cost of whatever resource is being exchanged against the finances. The other part is the profit of the entity that obtains the finances. From the viewpoint of that entity, the first part vs. the resource given is zero-sum – its incentive to participate in this exchange is the second part, the profit. That second part is effectively the trickle in the system, as it is the only resource really gained.

The direction and the size of the trickle ultimately depends on the balance of many factors, some of them random, others constant. On the long run, it is the constant factors that determine the size and the direction of the trickle sum.

The most important constant factor is the benefit of scale (BOS). It dictates that the bigger entities are able to pull the balance to their side more strongly than the smaller ones. Some miss that chance, but others use it. It makes the trickle-up stronger than the trickle-down. In a system where the transaction outcome is close to a zero-sum game, this concentrates all resources at the top with a speed depending on the financial interactions volume per an unit of time.

(Actually the formula is a bit more complex. All dynamic entities – eg. living organisms, active companies etc – have an “existence maintenance” expense, which they cannot avoid. However, the amount of resources in a system above the summary existence maintenance follows the simple rule above. And these are the only resources that are available for investing in anything, eg. development.)

In the real-life systems the BOS power is limited. There are many different random factors that compete with and influence one another, some of them outweighing BOS. Also, in every moment some factors lose importance and / or cease to exist, while others appear and / or gain importance. The complexity of this system makes any attempt by an entity or entities pool to take control over it hard and slow. This gives the other entities time and ways to react and try to block the takeover attempt. Also, the real-life systems have many built-in constraints against scale-based takeovers – anti-trust laws, separation of the government powers, enforced financial trickle-down through taxes on the rich and benefits for the poor, etc. All these together manage to prevent most takeover attempts, or to limit them into only a segment of the system.

How a Proof-of-Stake based cryptocurrency fares at these?

A POS-based cryptocurrency financial system has no constraints against scale-based takeovers. It has only one kind of clout – the amount of resources controlled by an entity. This kind of clout is built in it, has all the importance in it and cannot lose that or disappear. It has no other types of resources, and has no slowing due to complexity. It is not segmented – who has these resources has it all. There are no built-in constraints against scale-based takeovers, or mechanisms to strengthen resource trickle-down. In short, it is the ideal ground for creating a polarized financial system.

So, it would be only logical to expect that a Proof-of-Stake based Ether financial system will suffer by the problems a polarized system presents. Despite all of its technical ingenuity, its longer-term financial usability is limited, and the participation in it may be dangerous to any entity smaller than eg. a big bank, a big hedge fund or a big authoritarian state.

All fixes for this problem I could think of by now would be easily beaten by simple attacks. I am not sure if it is possible to have a reliable solution to it at all.

Do smart contracts and secondary tokens change this?

Unhappily, no. Smart contracts are based on having Ether, and need Ether to exist and act. Thus, they are bound to the financial situation of the Ether financial system, and are influenced by it. The bigger is the scope of the smart contract, the bigger is its dependence on the Ether situation.

Due to this, smart contracts of meaningful size will find themselves hampered and maybe even endangered by a polarization in the financial system powered by POS-based Ethereum. It is technically possible to migrate these contracts to a competing underlying system, but it won’t be easy – probably even when the competing system is technically a clone of Ethereum, like Ethereum Classic. The migration cost might exceed the migration benefits at any given stage of the contract project development, even if the total migration benefits are far larger than this cost.

Eventually this problem might become public knowledge and most projects in need of a smart contract might start avoiding Ethereum. This will lead to decreased interest in participation in the Ethereum ecosystem, to a loss of market cap, and eventually maybe even to the demise of this technically great project.

Other dangers

There is a danger that the “haves” minority in a polarized system might start actively investing resources in creating other systems that suffer from the same problem (as they benefit from it), or in modifying existing systems in this direction. This might decrease the potential for development globally. As some of the backers of Ethereum are entities with enormous clout worldwide, that negative influence on the global system might be significant.

Kodi Security Risk Emerges After TVAddons Shutdown

Post Syndicated from Andy original https://torrentfreak.com/kodi-security-risk-emerges-after-tvaddons-shutdown-170723/

Formerly known as XBMC, the popularity of the entirely legal Kodi media player has soared in recent years.

Controversial third-party addons that provide access to infringing content have thrust Kodi into the mainstream and the product is now a household name.

Until recently, TVAddons.ag was the leading repository for these addons. During March, the platform had 40 million unique users connected to the site’s servers, together transferring an astounding petabyte of addons and updates.

Everything was going well until news broke last month that the people behind TVAddons were being sued in a federal court in Texas. Shortly after the site went dark and hasn’t been back since.

This was initially a nuisance to the millions of Kodi devices that relied on TVAddons for their addons and updates. With the site gone, none were forthcoming. However, the scene recovered relatively quickly and for users who know what they’re doing, addons are now available from elsewhere.

That being said, something very unusual happened this week. Out of the blue, several key TVAddons domains were transferred to a Canadian law firm. TVAddons, who have effectively disappeared, made no comment. The lawyer involved, Daniel Drapeau, ignored requests for an explanation.

While that’s unusual enough, there’s a bigger issue at play here for millions of former TVAddons users who haven’t yet wiped their devices or upgraded them to work with other repositories.

Without going into huge technical detail, any user of an augmented Kodi device that relied on TVAddons domains (TVAddons.ag, Offshoregit.com) for updates can be reasonably confident that the domains their device is now accessing are not controlled by TVAddons anymore. That is not good news.

When a user installs a Kodi addon or obtains an update, the whole system is based on human trust. People are told about a trustworthy source (repository or ‘repo’) and they feel happy getting their addons and updates from it.

However, any person in control of a repo can make a Kodi addon available that can do pretty much anything. When that’s getting free movies, people tend to be happy, but when that’s making a botnet out of set-top boxes, enthusiasm tends to wane a bit.

If the penny hasn’t yet dropped, consider this.

TVAddons’ domains are now being run by a law firm which refuses to answer questions but has the power to do whatever it likes with them, within the law of course. Currently, the domains are lying dormant and aren’t doing anything nefarious, but if that position changes, millions of people will have absolutely no idea anything is wrong.

TorrentFreak spoke to Kodi Project Manager Nathan Betzen who agrees that the current security situation probably isn’t what former TVAddons users had in mind.

“These are unsandboxed Python addons. The person [in control of] the repo could do whatever they wanted. You guys wrote about the addon that created a DDoS event,” Betzen says.

“If some malware author wanted, he could easily install a watcher that reports back the user’s IP address and everything they were doing in Kodi. If the law firm is actually an anti-piracy group, that seems like the likeliest thing I can think of,” he adds.

While nothing can be ruled out, it seems more likely that the law firm in question has taken control of TVAddons’ domains in order to put them out of action, potentially as part of a settlement in the Dish Network lawsuit. However, since it refuses to answer any questions, everything is open to speculation.

Another possibility is that the domains are being held pending sale, which then raises questions over who the buyer might be and what their intentions are. The bottom line is we simply do not know and since nobody is talking, it might be prudent to consider the worst case scenario.

“If it’s just a holding group, then people [in control of the domain/repo] could do whatever they can think of. Want a few million incredibly inefficient bit mining boxes?” Betzen speculates.

While this scenario is certainly a possibility, one would at least like to think of it as unlikely. That being said, plenty of Internet security fails can be attributed to people simply hoping for the best when things go bad. That rarely works.

On the plus side, Betzen says that since Python code is usually pretty easy to read, any nefarious action could be spotted by vigilant members of the community fairly quickly. However, Martijn Kaijser from Team Kodi warns that it’s possible to ship precompiled Python code instead of the readable versions.

“You can’t even see what’s in the Python files and what they do,” he notes.

Finally, there’s a possibility that TVAddons may be considering some kind of comeback. Earlier this week a new domain – TVAddons.co – was freshly registered, just after the old domains shifted to the law firm. At this stage, however, nothing is known about the site’s plans.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

Kim Dotcom Denied Access to Illegally Obtained Spy Recordings

Post Syndicated from Andy original https://torrentfreak.com/kim-dotcom-denied-access-to-illegally-obtained-spy-recordings-170720/

In the months leading up to the infamous raid on Kim Dotcom’s New Zealand mansion and his now defunct cloud storage site Megaupload, the entrepreneur was under surveillance.

Not only were the MPAA and RIAA amassing information, the governments of the United States and New Zealand were neck-deep in the investigation too, using the FBI and local police to gather information. What soon became evident, however, is that the authorities in New Zealand did so while breaking the rules.

Between 16 December 2011 to 22 March 2012, New Zealand used the Government Communications Security Bureau (GCSB) agency to spy on the private communications of Kim and Mona Dotcom, plus Megaupload co-defendant Bram van der Kolk. This was hugely problematic.

GCSB is an intelligence agency of the New Zealand government responsible for spying on external entities. It is forbidden by law from conducting surveillance on its own citizens or permanent residents in the country. His standing in the country meant that Dotcom should not have been spied on.

“Of course I apologize to Mr Dotcom, and I apologize to New Zealanders,” then New Zealand Prime Minister John Key later said.

Since it was established that New Zealand illegally spied on Dotcom, the Megaupload founder has been trying to find out what information the GCSB gathered about him, then wife Mona, and former colleague Bram van der Kolk. According to Dotcom, there was a total of 87 breaches, all of which the government wants to keep secret.

Since then, Dotcom has been fighting to gain access to the information GCSB illegally obtained, while seeking compensation for the damages caused.

In a ruling handed down this morning, the High Court details its findings in respect of a three-day hearing that took place early April 2017, during which GCSB said the raw, unredacted information should be withheld from Dotcom on national security grounds.

GCSB and the government argued that the public interest in the disclosure of the material is outweighed by the public interest in withholding it, adding that the security and defense of New Zealand would be compromised on the world stage.

For their part, the Dotcoms said that nondisclosure of the unredacted documents breaches their rights under the New Zealand Bill of Rights Act 1990. Given that any damages award is directly linked to the extent and nature of the illegal intrusions into their private lives, access to the documents is paramount.

That being the case, they argued that the public interest in disclosure outweighs any public interest in the information being withheld.

This morning, citing a 2013 Court of Appeal verdict that ruled the GCSB didn’t have to release the raw communications, Justice Murray Gilbert insisted that the recordings will not be released.

“A number of the redactions in the discovered documents are to protect the identity or contact details of personnel who were involved in or associated with the operation or copied into email communications concerning it,” Justice Gilbert wrote.

“It is hard to see how any of this information could be relevant to the relief that should be granted in this proceeding. Again, the public interest in withholding disclosure of this information far outweighs any public interest in its disclosure.”

In a statement, Kim Dotcom expressed his frustrations, noting that the government is doing everything it can to suppress details of the illegal surveillance.

“After being caught, the GCSB has fought to keep what it did, and how, a secret from me and from you, the New Zealand public. Worse, it seeks to hide behind ‘national security’ to keep the truth from us,” Dotcom said.

“To keep this secret, the GCSB applied to the High Court. It filed secret evidence and secret submissions. The GCSB’s lawyers were heard in a ‘closed’ court with the Judge, where they made secret submissions and secret witnesses gave secret evidence.”

Dotcom said neither his lawyers nor the public was allowed to be present during the hearing. And when his legal team could be heard, they were significantly hampered in their work.

“When my lawyers were heard, after that hearing, they had to make submissions as to why information they were not allowed to see, for reasons they were not allowed to know, should be disclosed. They were effectively shooting at a moving target, in the dark, with one hand tied behind their backs,” Dotcom said.

The Megaupload founder suggests there is there is a clear double-standard when he has to be tried in public for his alleged crimes, but when it comes to offenses carried out by the government, the process takes place behind closed doors.

“I will appeal this judgment and ask the Court of Appeal to shine some cleansing sunlight on what happened here. If there is transparency, there is accountability, and we can prevent this happening again,” he concludes.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

Several TVAddons Domains Transferred to Canadian Lawfirm

Post Syndicated from Andy original https://torrentfreak.com/several-tvaddons-domains-transferred-to-canadian-lawfirm-170718/

The last couple of months have been the most chaotic on record for the booming Kodi third-party addon scene. After years of largely interrupted service, a single lawsuit changed the entire landscape.

Last month, TF broke the news that third-party Kodi add-on ZemTV and the TVAddons library were being sued in a federal court in Texas. The fallout was something to behold.

Within days the ‘pirate’ Kodi community found itself in turmoil. Several high-profile Kodi addons took the decision to shut down and even TVAddons itself went dark without explanation.

At the time, unsubstantiated rumors suggested that TVAddons’ disappearance could be attributed to some coincidental site maintenance. However, with around 40 million regular users built up over a number of years, a disappearing Facebook page, and complete radio silence during alleged “routine maintenance,” something was clearly wrong.

It would’ve taken just a couple of minutes to put a ‘maintenance’ notice on the site but one didn’t appear back in June, and one hasn’t appeared since. Behind the scenes,
however, things have been shifting.

In addition to wiping the DNS entries of TVAddons.ag, on at least another couple of occasions the domain has been quietly updated. The image below shows how it used to look.

TVAddons historical domain WHOIS

PrivacyDotLink refers to a service offered by Cayman Islands-based registry Uniregistry. Instead of displaying the real name and address of the domain owner (in this case the person behind TVAddons.ag), the registry replaces the information with details of its own.

The privacy service is used for many reasons, but it’s not hard to see why it’s of particular use to sites in the ‘pirate’ sector.

While some of the changes to the TVAddons domain during the past five weeks or so haven’t been obvious, this morning we observed the biggest change yet. As seen in the image below, its ownership details are no longer obscured by the privacy service.

TVAddons new domain WHOIS

What stands out here is the name Daniel Drapeau. On closer inspection, this gentleman turns out to be a Canada-based lawyer who was admitted to the Quebec Bar in 1991.

“A passion for IP and a 20 year track record, servicing corporations and individuals alike in a wide variety of industries, including industrial equipment, consumer products, publishing, food & beverage, fashion and arts,” Drapeau’s Linkedin page reads.

“His forte is the strategic use of IP rights and litigation to achieve his clients’ goals, whether they be protective, aggressive or defensive. Specialties: Expeditive remedies, including injunctions and seizure orders.”

The other fresh detail in the WHOIS is an address – 600, de Maisonneuve West, Montreal (Quebec) H3A 3J2. It’s a perfect match for the premises of DrapeauLex, a law firm launched by Drapeau in 2012.

Only adding to the intrigue is the fact that other domains operated by TVAddons both recently and historically have also been transferred to the lawfirm.

XMBCHUB.com, which was the domain used by TVAddons before making the switch several years ago, was transferred yesterday. The same can be said about Offshoregit.com, the domain used by TVAddons to distribute Kodi addons.

While there are a few explanations for a lawyer’s name appearing on the TVAddons domains, none of them are yet supported by legal documentation filed in the United States. As of this morning, the Dish Network case docket had received no additional updates. No notice of action in Canada has been made public.

Nevertheless, as a past president of the Intellectual Property Institute of Canada’s anti-counterfeiting committee, Drapeau is certainly an interesting character in the IP space. As noted in a 2009 article by Professor of Law Michael Geist, Drapeau “urged the government to adopt a system of notice-and-takedown.”

Interestingly, Drapeau also worked at law firm Smart & Biggar, where former colleague Jean-Sébastien Dupont recently went on to represent Canadian broadcasters in Wesley (Mtlfreetv.com) v. Bell Canada, the big Kodi-addon piracy case currently underway in Canada.

At this stage, it’s unclear who Drapeau is working for in the TVAddons case. It’s possible that he’s working for Dish and this is a step towards the domains being handed over to the broadcaster as part of a settlement deal with TVAddons. That being said, the XBMChub and Offshoregit domains weren’t mentioned in the Dish lawsuit so something else might be underway.

TorrentFreak reached out to Drapeau for comment and clarification, but at the time of publication, we had received no response.

Dan Drapeau talks Intellectual Property from DrapeauLex on Vimeo.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

Court: Warner Bros Needs Stronger Evidence Against Alleged BitTorrent Pirate

Post Syndicated from Ernesto original https://torrentfreak.com/court-warner-bros-needs-stronger-evidence-against-alleged-bittorrent-pirate-170718/

Over the past decade, copyright holders have gone after hundreds of thousands of alleged pirates in Germany, demanding settlements ranging from a few hundred to thousands of euros.

The targeted account holders are often indeed the perpetrator, but false accusations are bound to happen due to the sheer volume of these cases.

This is one of the reasons why local courts are paying careful attention to the provided evidence. At the District Court of Cologne, this recently resulted in a verdict, clarifying that simply linking an IP-address to a pirated download is not good enough.

The case in question deals with a claim from the local branch of Warner Bros. Entertainment, which accused an account holder of sharing a pirated episode of the popular TV-show “Person of Interest.”

The Hollywood studio claimed 500 euros in damages from the alleged copyright infringer, as well as 168.50 euros in expenses. The defendant, however, said he was innocent, refused to pay up, and contested the claim in court, with success.

Warner’s tracking partner Ipoque had only monitored the defendant’s IP-address twice during a period of 10 minutes. This is not good enough according to the court, since IP-address misassignments regularly take place.

“The causes for a misassignment don’t have to relate to the software of the tracking company, they can also come from others. For example, the transmission of acquired data, or the ISPs assignment of collected IP addresses to connection holders. In the latter case, the Court of First Instance has seen an error rate of at least 2 – 3%,” the court writes.

In this case, the defendant argued that his ISP failed to update the IP-address assignments and that he no longer used the infringing address at the contested time.

The District Court of Cologne agreed that this was a plausible argument. Ideally, Warner should have provided a more extensive tracking record, with more IP-addresses leading to the same account holder, assuming that the assignments regularly change.

Defense attorney Christian Solmecke tells TorrentFreak that so-called “simple tracking,” where only a single IP-address is used as evidence, is simply not good enough.

“In case of simple tracking, evaluation errors are always possible. For instance, mixing up the numbers of the IP-address. The tracking parameters are technically complicated so errors may occur at various stages of the process,” Solmecke notes.

In some cases the error rates can go up to 50%, a recent verdict has shown, which means that accused file-sharers have a solid defense when they are accused based on minimal evidence.

“This is important for defendants as courts usually tend to assume that it cannot be sufficiently clarified whether filesharing did indeed occur via the Internet connection of the defendant. Simple tracking can, therefore, be seen as a good chance for defendants to win against the warning letter industry,” Solmecke adds.

While the verdict is unlikely to stop the piracy settlement industry in Germany, it may prompt rightsholders to step up their BitTorrent monitoring practices.

This doesn’t only apply to Warner Bros. Entertainment, but also to other major rightsholders including the local branches of Universal Pictures, Twentieth Century Fox, Universal Music, EMI Music and Sony Music, which are all active on the anti-piracy front in Germany.

The full verdict of the District Court of Cologne is available Tarnkappe.

Source: TF, for the latest info on copyright, file-sharing, torrent sites and ANONYMOUS VPN services.

Guest post: How EmailOctopus built an email marketing platform using Amazon SES

Post Syndicated from Brent Meyer original https://aws.amazon.com/blogs/ses/guest-post-how-emailoctopus-built-an-email-marketing-platform-using-amazon-ses/

The following guest post was written by Tom Evans, COO of EmailOctopus.


Our product, EmailOctopus, grew from a personal need. We were working on another business venture, and as our email subscriber base grew, the costs of using the larger email service providers became prohibitively expensive for an early-stage startup.

At this point we were already using Amazon SES to send sign up confirmations to our users. We loved Amazon SES’ low pricing and high deliverability, but being a transactional email service, we missed some tracking features offered by our marketing provider. We decided to develop a simple interface to make it easier for us to build and track the performance of marketing emails on top of the Amazon SES platform.

After sharing our accomplishments with other founders, and with no other SaaS solutions on the market that met the same need, we began to turn our basic script into a polished email marketing application. We named our application EmailOctopus. Over 4 years later, and with over 1.5 billion emails delivered through Amazon SES, our mission remains the same: to make contacting your customers as easy and inexpensive as possible.

EmailOctopus is now a fully fledged platform, with thousands of users sending marketing campaigns every day. Our platform integrates directly with our customers’ AWS accounts and provides them with an easy-to-use front end on top of the SES platform. EmailOctopus users can upload or register subscribers who have opted into their correspondence (through an import or one of our many integrations), then send a one-off campaign or an automated marketing series, all while closely tracking the performance of those emails and allowing the recipients to opt-out.

Scaling EmailOctopus to handle millions of emails per day

Building an email marketing platform from scratch has presented a number of challenges, both technical and operational. EmailOctopus has quickly grown from a side project to a mature business that has sent over 1.5 billion emails through Amazon SES.

One of the biggest challenges of our growth has been dealing with a rapidly expanding database. Email marketing generates a huge amount of data. We log every view, bounce, click, spam report, open and unsubscribe for every email sent through our platform. A single campaign can easily generate over 1 million of these events.

Our event processing system sits on a number of microservices spread over EC2 and Lambda, which allows us to selectively scale our services based on demand. Figure 1, below, demonstrates just how irregular this demand is. We save over $500 a month using an on-demand serverless model.

Figure 1. Number of events processed over time.

This model helps us manage our costs and ensures we only pay for the computing power we need.  We rely heavily on CloudFormation scripts to edit that infrastructure; these scripts allow every change to be version-controlled and propagated across all of our environments. In preparing for this blog post, we took a look at how that template had changed over the years—we’d forgotten just how much it had evolved. As our user base grew from 1 customer to 10,000, a single EC2 instance writing to a MySQL database just didn’t cut it. We now rely on a large portion of the AWS suite to reliably consume our event data, as illustrated in Figure 2, below.

Figure 2. Our current event processing infrastructure.

Operationally, our business has needed to make changes to scale too. Processes that worked fine with a handful of clients do not work so well with 10,000 users. We pride ourselves on providing our customers with a superior and personal service; to maintain that commitment, we dedicate 10% of our development time to improving our internal tools. One of these projects resulted in a dashboard which quickly provides us with detailed information on each user and their journey through the platform. The days of asking our support team to assemble database queries are long gone!

What makes EmailOctopus + SES different from the competition?

Amazon SES uses proprietary content filtering technologies and monitors the status of its services rigorously. This means that you’re likely to see increased deliverability on your communication, while saving up to 10x on your current email marketing costs. EmailOctopus pricing plans range from $0 to $109 per month (depending on the number of recipients you need to store), and the cost of sending email through Amazon SES is also very low: you pay nothing for the first 62,000 emails you send through Amazon SES each month, and $0.10 per 1,000 emails after that. Need to send a million emails in a month? You can do it for less than $100 with EmailOctopus + Amazon SES.

Our easy-to-use interface and integrations make it easy to add new subscribers, and our email templates help you create trackable, beautiful, responsive emails. We even offer trigger-based automated email delivery—perfect for onboarding new customers.

I’m ready to get started!

Great! We’ve made it easy to start using EmailOctopus with Amazon SES. First, if you don’t already have one, create an Amazon Web Services account. Once you’ve done that, head over to our website and create an EmailOctopus account. From there, we’ll walk you through the quick and easy process of linking the two services together.

If you’ve never used Amazon SES before, you will also need to provide some information about the types of communication you plan to send. This important step in the process ensures that all new Amazon SES users are reputable, and that they will not have a negative impact on other users who send email through Amazon SES. Once you’ve finished that step, you’ll be ready to start sending emails using EmailOctopus and Amazon SES.

To learn more about what EmailOctopus can do for your business, visit our website at https://emailoctopus.com.

 

PenTools – Penetration Testing Tools Bundle

Post Syndicated from Darknet original http://feedproxy.google.com/~r/darknethackers/~3/LSfV9g_sP6g/

PenTools is a bundle of Python and Bash penetration testing tools for the recon and information gathering stage of a PT or VA. They are fairly simple scripts but might be interesting if you are new and want to see how some things are done, or how things can be automated using Python or Bash. […]

The post PenTools – Penetration Testing…

Read the full post at darknet.org.uk

Continuous Delivery of Nested AWS CloudFormation Stacks Using AWS CodePipeline

Post Syndicated from Prakash Palanisamy original https://aws.amazon.com/blogs/devops/continuous-delivery-of-nested-aws-cloudformation-stacks-using-aws-codepipeline/

In CodePipeline Update – Build Continuous Delivery Workflows for CloudFormation Stacks, Jeff Barr discusses infrastructure as code and how to use AWS CodePipeline for continuous delivery. In this blog post, I discuss the continuous delivery of nested CloudFormation stacks using AWS CodePipeline, with AWS CodeCommit as the source repository and AWS CodeBuild as a build and testing tool. I deploy the stacks using CloudFormation change sets following a manual approval process.

Here’s how to do it:

In AWS CodePipeline, create a pipeline with four stages:

  • Source (AWS CodeCommit)
  • Build and Test (AWS CodeBuild and AWS CloudFormation)
  • Staging (AWS CloudFormation and manual approval)
  • Production (AWS CloudFormation and manual approval)

Pipeline stages, the actions in each stage, and transitions between stages are shown in the following diagram.

CloudFormation templates, test scripts, and the build specification are stored in AWS CodeCommit repositories. These files are used in the Source stage of the pipeline in AWS CodePipeline.

The AWS::CloudFormation::Stack resource type is used to create child stacks from a master stack. The CloudFormation stack resource requires the templates of the child stacks to be stored in the S3 bucket. The location of the template file is provided as a URL in the properties section of the resource definition.

The following template creates three child stacks:

  • Security (IAM, security groups).
  • Database (an RDS instance).
  • Web stacks (EC2 instances in an Auto Scaling group, elastic load balancer).
Description: Master stack which creates all required nested stacks

Parameters:
  TemplatePath:
    Type: String
    Description: S3Bucket Path where the templates are stored
  VPCID:
    Type: "AWS::EC2::VPC::Id"
    Description: Enter a valid VPC Id
  PrivateSubnet1:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of private subnet in AZ1
  PrivateSubnet2:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of private subnet in AZ2
  PublicSubnet1:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of public subnet in AZ1
  PublicSubnet2:
    Type: "AWS::EC2::Subnet::Id"
    Description: Enter a valid SubnetId of public subnet in AZ2
  S3BucketName:
    Type: String
    Description: Name of the S3 bucket to allow access to the Web Server IAM Role.
  KeyPair:
    Type: "AWS::EC2::KeyPair::KeyName"
    Description: Enter a valid KeyPair Name
  AMIId:
    Type: "AWS::EC2::Image::Id"
    Description: Enter a valid AMI ID to launch the instance
  WebInstanceType:
    Type: String
    Description: Enter one of the possible instance type for web server
    AllowedValues:
      - t2.large
      - m4.large
      - m4.xlarge
      - c4.large
  WebMinSize:
    Type: String
    Description: Minimum number of instances in auto scaling group
  WebMaxSize:
    Type: String
    Description: Maximum number of instances in auto scaling group
  DBSubnetGroup:
    Type: String
    Description: Enter a valid DB Subnet Group
  DBUsername:
    Type: String
    Description: Enter a valid Database master username
    MinLength: 1
    MaxLength: 16
    AllowedPattern: "[a-zA-Z][a-zA-Z0-9]*"
  DBPassword:
    Type: String
    Description: Enter a valid Database master password
    NoEcho: true
    MinLength: 1
    MaxLength: 41
    AllowedPattern: "[a-zA-Z0-9]*"
  DBInstanceType:
    Type: String
    Description: Enter one of the possible instance type for database
    AllowedValues:
      - db.t2.micro
      - db.t2.small
      - db.t2.medium
      - db.t2.large
  Environment:
    Type: String
    Description: Select the appropriate environment
    AllowedValues:
      - dev
      - test
      - uat
      - prod

Resources:
  SecurityStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/security-stack.yml"
      Parameters:
        S3BucketName:
          Ref: S3BucketName
        VPCID:
          Ref: VPCID
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value: SecurityStack

  DatabaseStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/database-stack.yml"
      Parameters:
        DBSubnetGroup:
          Ref: DBSubnetGroup
        DBUsername:
          Ref: DBUsername
        DBPassword:
          Ref: DBPassword
        DBServerSecurityGroup:
          Fn::GetAtt: SecurityStack.Outputs.DBServerSG
        DBInstanceType:
          Ref: DBInstanceType
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value:   DatabaseStack

  ServerStack:
    Type: "AWS::CloudFormation::Stack"
    Properties:
      TemplateURL:
        Fn::Sub: "https://s3.amazonaws.com/${TemplatePath}/server-stack.yml"
      Parameters:
        VPCID:
          Ref: VPCID
        PrivateSubnet1:
          Ref: PrivateSubnet1
        PrivateSubnet2:
          Ref: PrivateSubnet2
        PublicSubnet1:
          Ref: PublicSubnet1
        PublicSubnet2:
          Ref: PublicSubnet2
        KeyPair:
          Ref: KeyPair
        AMIId:
          Ref: AMIId
        WebSG:
          Fn::GetAtt: SecurityStack.Outputs.WebSG
        ELBSG:
          Fn::GetAtt: SecurityStack.Outputs.ELBSG
        DBClientSG:
          Fn::GetAtt: SecurityStack.Outputs.DBClientSG
        WebIAMProfile:
          Fn::GetAtt: SecurityStack.Outputs.WebIAMProfile
        WebInstanceType:
          Ref: WebInstanceType
        WebMinSize:
          Ref: WebMinSize
        WebMaxSize:
          Ref: WebMaxSize
        Environment:
          Ref: Environment
      Tags:
        - Key: Name
          Value: ServerStack

Outputs:
  WebELBURL:
    Description: "URL endpoint of web ELB"
    Value:
      Fn::GetAtt: ServerStack.Outputs.WebELBURL

During the Validate stage, AWS CodeBuild checks for changes to the AWS CodeCommit source repositories. It uses the ValidateTemplate API to validate the CloudFormation template and copies the child templates and configuration files to the appropriate location in the S3 bucket.

The following AWS CodeBuild build specification validates the CloudFormation templates listed under the TEMPLATE_FILES environment variable and copies them to the S3 bucket specified in the TEMPLATE_BUCKET environment variable in the AWS CodeBuild project. Optionally, you can use the TEMPLATE_PREFIX environment variable to specify a path inside the bucket. This updates the configuration files to use the location of the child template files. The location of the template files is provided as a parameter to the master stack.

version: 0.1

environment_variables:
  plaintext:
    CHILD_TEMPLATES: |
      security-stack.yml
      server-stack.yml
      database-stack.yml
    TEMPLATE_FILES: |
      master-stack.yml
      security-stack.yml
      server-stack.yml
      database-stack.yml
    CONFIG_FILES: |
      config-prod.json
      config-test.json
      config-uat.json

phases:
  install:
    commands:
      npm install jsonlint -g
  pre_build:
    commands:
      - echo "Validating CFN templates"
      - |
        for cfn_template in $TEMPLATE_FILES; do
          echo "Validating CloudFormation template file $cfn_template"
          aws cloudformation validate-template --template-body file://$cfn_template
        done
      - |
        for conf in $CONFIG_FILES; do
          echo "Validating CFN parameters config file $conf"
          jsonlint -q $conf
        done
  build:
    commands:
      - echo "Copying child stack templates to S3"
      - |
        for child_template in $CHILD_TEMPLATES; do
          if [ "X$TEMPLATE_PREFIX" = "X" ]; then
            aws s3 cp "$child_template" "s3://$TEMPLATE_BUCKET/$child_template"
          else
            aws s3 cp "$child_template" "s3://$TEMPLATE_BUCKET/$TEMPLATE_PREFIX/$child_template"
          fi
        done
      - echo "Updating template configurtion files to use the appropriate values"
      - |
        for conf in $CONFIG_FILES; do
          if [ "X$TEMPLATE_PREFIX" = "X" ]; then
            echo "Replacing \"TEMPLATE_PATH_PLACEHOLDER\" for \"$TEMPLATE_BUCKET\" in $conf"
            sed -i -e "s/TEMPLATE_PATH_PLACEHOLDER/$TEMPLATE_BUCKET/" $conf
          else
            echo "Replacing \"TEMPLATE_PATH_PLACEHOLDER\" for \"$TEMPLATE_BUCKET/$TEMPLATE_PREFIX\" in $conf"
            sed -i -e "s/TEMPLATE_PATH_PLACEHOLDER/$TEMPLATE_BUCKET\/$TEMPLATE_PREFIX/" $conf
          fi
        done

artifacts:
  files:
    - master-stack.yml
    - config-*.json

After the template files are copied to S3, CloudFormation creates a test stack and triggers AWS CodeBuild as a test action.

Then the AWS CodeBuild build specification executes validate-env.py, the Python script used to determine whether resources created using the nested CloudFormation stacks conform to the specifications provided in the CONFIG_FILE.

version: 0.1

environment_variables:
  plaintext:
    CONFIG_FILE: env-details.yml

phases:
  install:
    commands:
      - pip install --upgrade pip
      - pip install boto3 --upgrade
      - pip install pyyaml --upgrade
      - pip install yamllint --upgrade
  pre_build:
    commands:
      - echo "Validating config file $CONFIG_FILE"
      - yamllint $CONFIG_FILE
  build:
    commands:
      - echo "Validating resources..."
      - python validate-env.py
      - exit $?

Upon successful completion of the test action, CloudFormation deletes the test stack and proceeds to the UAT stage in the pipeline.

During this stage, CloudFormation creates a change set against the UAT stack and then executes the change set. This updates the UAT environment and makes it available for acceptance testing. The process continues to a manual approval action. After the QA team validates the UAT environment and provides an approval, the process moves to the Production stage in the pipeline.

During this stage, CloudFormation creates a change set for the nested production stack and the process continues to a manual approval step. Upon approval (usually by a designated executive), the change set is executed and the production deployment is completed.
 

Setting up a continuous delivery pipeline

 
I used a CloudFormation template to set up my continuous delivery pipeline. The codepipeline-cfn-codebuild.yml template, available from GitHub, sets up a full-featured pipeline.

When I use the template to create my pipeline, I specify the following:

  • AWS CodeCommit repositories.
  • SNS topics to send approval notifications.
  • S3 bucket name where the artifacts will be stored.

The CFNTemplateRepoName points to the AWS CodeCommit repository where CloudFormation templates, configuration files, and build specification files are stored.

My repo contains following files:

The continuous delivery pipeline is ready just seconds after clicking Create Stack. After it’s created, the pipeline executes each stage. Upon manual approvals for the UAT and Production stages, the pipeline successfully enables continuous delivery.


 

Implementing a change in nested stack

 
To make changes to a child stack in a nested stack (for example, to update a parameter value or add or change resources), update the master stack. The changes must be made in the appropriate template or configuration files and then checked in to the AWS CodeCommit repository. This triggers the following deployment process:

 

Conclusion

 
In this post, I showed how you can use AWS CodePipeline, AWS CloudFormation, AWS CodeBuild, and a manual approval process to create a continuous delivery pipeline for both infrastructure as code and application deployment.

For more information about AWS CodePipeline, see the AWS CodePipeline documentation. You can get started in just a few clicks. All CloudFormation templates, AWS CodeBuild build specification files, and the Python script that performs the validation are available in codepipeline-nested-cfn GitHub repository.


About the author

 
Prakash Palanisamy is a Solutions Architect for Amazon Web Services. When he is not working on Serverless, DevOps or Alexa, he will be solving problems in Project Euler. He also enjoys watching educational documentaries.

From Idea to Launch: Getting Your First Customers

Post Syndicated from Gleb Budman original https://www.backblaze.com/blog/how-to-get-your-first-customers/

line outside of Apple

After deciding to build an unlimited backup service and developing our own storage platform, the next step was to get customers and feedback. Not all customers are created equal. Let’s talk about the types, and when and how to attract them.

How to Get Your First Customers

First Step – Don’t Launch Publicly
Launch when you’re ready for the judgments of people who don’t know you at all. Until then, don’t launch. Sign up users and customers either that you know, those you can trust to cut you some slack (while providing you feedback), or at minimum those for whom you can set expectations. For months the Backblaze website was a single page with no ability to get the product and minimal info on what it would be. This is not to counter the Lean Startup ‘iterate quickly with customer feedback’ advice. Rather, this is an acknowledgement that there are different types of feedback required based on your development stage.

Sign Up Your Friends
We knew all of our first customers; they were friends, family, and previous co-workers. Many knew what we were up to and were excited to help us. No magic marketing or tech savviness was required to reach them – we just asked that they try the service. We asked them to provide us feedback on their experience and collected it through email and conversations. While the feedback wasn’t unbiased, it was nonetheless wide-ranging, real, and often insightful. These people were willing to spend time carefully thinking about their feedback and delving deeper into the conversations.

Broaden to Beta
Unless you’re famous or your service costs $1 million per customer, you’ll probably need to expand quickly beyond your friends to build a business – and to get broader feedback. Our next step was to broaden the customer base to beta users.

Opening up the service in beta provides three benefits:

  1. Air cover for the early warts. There are going to be issues, bugs, unnecessarily complicated user flows, and poorly worded text. Beta tells people, “We don’t consider the product ‘done’ and you should expect some of these issues. Please be patient with us.”
  2. A request for feedback. Some people always provide feedback, but beta communicates that you want it.
  3. An awareness opportunity. Opening up in beta provides an early (but not only) opportunity to have an announcement and build awareness.

Pitching Beta to Press
Not all press cares about, or is even willing to cover, beta products. Much of the mainstream press wants to write about services that are fully live, have scale, and are important in the marketplace. However, there are a number of sites that like to cover the leading edge – and that means covering betas. Techcrunch, Ars Technica, and SimpleHelp covered our initial private beta launch. I’ll go into the details of how to work with the press to cover your announcements in a post next month.

Private vs. Public Beta
Both private and public beta provide all three of the benefits above. The difference between the two is that private betas are much more controlled, whereas public ones bring in more users. But this isn’t an either/or – I recommend doing both.

Private Beta
For our original beta in 2008, we decided that we were comfortable with about 1,000 users subscribing to our service. That would provide us with a healthy amount of feedback and get some early adoption, while not overwhelming us or our server capacity, and equally important not causing cash flow issues from having to buy more equipment. So we decided to limit the sign-up to only the first 1,000 people who signed up; then we would shut off sign-ups for a while.

But how do you even get 1,000 people to sign up for your service? In our case, get some major publications to write about our beta. (Note: In a future post I’ll explain exactly how to find and reach out to writers. Sign up to receive all of the entrepreneurial posts in this series.)

Public Beta
For our original service (computer backup), we did not have a public beta; but when we launched Backblaze B2, we had a private and then a public beta. The private beta allowed us to work out early kinks, while the public beta brought us a more varied set of use cases. In public beta, there is no cap on the number of users that may try the service.

While this is a first-class problem to have, if your service is flooded and stops working, it’s still a problem. Think through what you will do if that happens. In our early days, when our system could get overwhelmed by volume, we had a static web page hosted with a different registrar that wouldn’t let customers sign up but would tell them when our service would be open again. When we reached a critical volume level we would redirect to it in order to at least provide status for when we could accept more customers.

Collect Feedback
Since one of the goals of betas is to get feedback, we made sure that we had our email addresses clearly presented on the site so users could send us thoughts. We were most interested in broad qualitative feedback on users’ experience, so all emails went to an internal mailing list that would be read by everyone at Backblaze.

For our B2 public and private betas, we also added an optional short survey to the sign-up process. In order to be considered for the private beta you had to fill the survey out, though we found that 80% of users continued to fill out the survey even when it was not required. This survey had both closed-end questions (“how much data do you have”) and open-ended ones (“what do you want to use cloud storage for?”).

BTW, despite us getting a lot of feedback now via our support team, Twitter, and marketing surveys, we are always open to more – you can email me directly at gleb.budman {at} backblaze.com.

Don’t Throw Away Users
Initially our backup service was available only on Windows, but we had an email sign-up list for people who wanted it for their Mac. This provided us with a sense of market demand and a ready list of folks who could be beta users and early adopters when we had a Mac version. Have a service targeted at doctors but lawyers are expressing interest? Capture that.

Product Launch

When
The first question is “when” to launch. Presuming your service is in ‘public beta’, what is the advantage of moving out of beta and into a “version 1.0”, “gold”, or “public availability”? That depends on your service and customer base. Some services fly through public beta. Gmail, on the other hand, was (in)famous for being in beta for 5 years, despite having over 100 million users.

The term beta says to users, “give us some leeway, but feel free to use the service”. That’s fine for many consumer apps and will have near zero impact on them. However, services aimed at businesses and government will often not be adopted with a beta label as the enterprise customers want to know the company feels the service is ‘ready’. While Backblaze started out as a purely consumer service, because it was a data backup service, it was important for customers to trust that the service was ready.

No product is bug-free. But from a product readiness perspective, the nomenclature should also be a reflection of the quality of the product. You can launch a product with one feature that works well out of beta. But a product with fifty features on which half the users will bump into problems should likely stay in beta. The customer feedback, surveys, and your own internal testing should guide you in determining this quality during the beta. Be careful about “we’ve only seen that one time” or “I haven’t been able to reproduce that on my machine”; those issues are likely to scale with customers when you launch.

How
Launching out of beta can be as simple as removing the beta label from the website/product. However, this can be a great time to reach out to press, write a blog post, and send an email announcement to your customers.

Consider thanking your beta testers somehow; can they get some feature turned out for free, an extension of their trial, or premium support? If nothing else, remember to thank them for their feedback. Users that signed up during your beta are likely the ones who will propel your service. They had the need and interest to both be early adopters and deal with bugs. They are likely the key to getting 1,000 true fans.

The Beginning
The title of this post was “Getting your first customers”, because getting to launch may feel like the peak of your journey when you’re pre-launch, but it really is just the beginning. It’s a step along the journey of building your business. If your launch is wildly successful, enjoy it, work to build on the momentum, but don’t lose track of building your business. If your launch is a dud, go out for a coffee with your team, say “well that sucks”, and then get back to building your business. You can learn a tremendous amount from your early customers, and they can become your biggest fans, but the success of your business will depend on what you continue to do the months and years after your launch.

The post From Idea to Launch: Getting Your First Customers appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

CoderDojo Coolest Projects 2017

Post Syndicated from Ben Nuttall original https://www.raspberrypi.org/blog/coderdojo-coolest-projects-2017/

When I heard we were merging with CoderDojo, I was delighted. CoderDojo is a wonderful organisation with a spectacular community, and it’s going to be great to join forces with the team and work towards our common goal: making a difference to the lives of young people by making technology accessible to them.

You may remember that last year Philip and I went along to Coolest Projects, CoderDojo’s annual event at which their global community showcase their best makes. It was awesome! This year a whole bunch of us from the Raspberry Pi Foundation attended Coolest Projects with our new Irish colleagues, and as expected, the projects on show were as cool as can be.

Coolest Projects 2017 attendee

Crowd at Coolest Projects 2017

This year’s coolest projects!

Young maker Benjamin demoed his brilliant RGB LED table tennis ball display for us, and showed off his brilliant project tutorial website codemakerbuddy.com, which he built with Python and Flask. [Click on any of the images to enlarge them.]

Coolest Projects 2017 LED ping-pong ball display
Coolest Projects 2017 Benjamin and Oly

Next up, Aimee showed us a recipes app she’d made with the MIT App Inventor. It was a really impressive and well thought-out project.

Coolest Projects 2017 Aimee's cook book
Coolest Projects 2017 Aimee's setup

This very successful OpenCV face detection program with hardware installed in a teddy bear was great as well:

Coolest Projects 2017 face detection bear
Coolest Projects 2017 face detection interface
Coolest Projects 2017 face detection database

Helen’s and Oly’s favourite project involved…live bees!

Coolest Projects 2017 live bees

BEEEEEEEEEEES!

Its creator, 12-year-old Amy, said she wanted to do something to help the Earth. Her project uses various sensors to record data on the bee population in the hive. An adjacent monitor displays the data in a web interface:

Coolest Projects 2017 Aimee's bees

Coolest robots

I enjoyed seeing lots of GPIO Zero projects out in the wild, including this robotic lawnmower made by Kevin and Zach:

Raspberry Pi Lawnmower

Kevin and Zach’s Raspberry Pi lawnmower project with Python and GPIO Zero, showed at CoderDojo Coolest Projects 2017

Philip’s favourite make was a Pi-powered robot you can control with your mind! According to the maker, Laura, it worked really well with Philip because he has no hair.

Philip Colligan on Twitter

This is extraordinary. Laura from @CoderDojo Romania has programmed a mind controlled robot using @Raspberry_Pi @coolestprojects

And here are some pictures of even more cool robots we saw:

Coolest Projects 2017 coolest robot no.1
Coolest Projects 2017 coolest robot no.2
Coolest Projects 2017 coolest robot no.3

Games, toys, activities

Oly and I were massively impressed with the work of Mogamad, Daniel, and Basheerah, who programmed a (borrowed) Amazon Echo to make a voice-controlled text-adventure game using Java and the Alexa API. They’ve inspired me to try something similar using the AIY projects kit and adventurelib!

Coolest Projects 2017 Mogamad, Daniel, Basheerah, Oly
Coolest Projects 2017 Alexa text-based game

Christopher Hill did a brilliant job with his Home Alone LEGO house. He used sensors to trigger lights and sounds to make it look like someone’s at home, like in the film. I should have taken a video – seeing it in action was great!

Coolest Projects 2017 Lego home alone house
Coolest Projects 2017 Lego home alone innards
Coolest Projects 2017 Lego home alone innards closeup

Meanwhile, the Northern Ireland Raspberry Jam group ran a DOTS board activity, which turned their area into a conductive paint hazard zone.

Coolest Projects 2017 NI Jam DOTS activity 1
Coolest Projects 2017 NI Jam DOTS activity 2
Coolest Projects 2017 NI Jam DOTS activity 3
Coolest Projects 2017 NI Jam DOTS activity 4
Coolest Projects 2017 NI Jam DOTS activity 5
Coolest Projects 2017 NI Jam DOTS activity 6

Creativity and ingenuity

We really enjoyed seeing so many young people collaborating, experimenting, and taking full advantage of the opportunity to make real projects. And we loved how huge the range of technologies in use was: people employed all manner of hardware and software to bring their ideas to life.

Philip Colligan on Twitter

Wow! Look at that room full of awesome young people. @coolestprojects #coolestprojects @CoderDojo

Congratulations to the Coolest Projects 2017 prize winners, and to all participants. Here are some of the teams that won in the different categories:

Coolest Projects 2017 winning team 1
Coolest Projects 2017 winning team 2
Coolest Projects 2017 winning team 3

Take a look at the gallery of all winners over on Flickr.

The wow factor

Raspberry Pi co-founder and Foundation trustee Pete Lomas came along to the event as well. Here’s what he had to say:

It’s hard to describe the scale of the event, and photos just don’t do it justice. The first thing that hit me was the sheer excitement of the CoderDojo ninjas [the children attending Dojos]. Everyone was setting up for their time with the project judges, and their pure delight at being able to show off their creations was evident in both halls. Time and time again I saw the ninjas apply their creativity to help save the planet or make someone’s life better, and it’s truly exciting that we are going to help that continue and expand.

Even after 8 hours, enthusiasm wasn’t flagging – the awards ceremony was just brilliant, with ninjas high-fiving the winners on the way to the stage. This speaks volumes about the ethos and vision of the CoderDojo founders, where everyone is a winner just by being part of a community of worldwide friends. It was a brilliant introduction, and if this weekend was anything to go by, our merger certainly is a marriage made in Heaven.

Join this awesome community!

If all this inspires you as much as it did us, consider looking for a CoderDojo near you – and sign up as a volunteer! There’s plenty of time for young people to build up skills and start working on a project for next year’s event. Check out coolestprojects.com for more information.

The post CoderDojo Coolest Projects 2017 appeared first on Raspberry Pi.

How to Create an AMI Builder with AWS CodeBuild and HashiCorp Packer – Part 2

Post Syndicated from Heitor Lessa original https://aws.amazon.com/blogs/devops/how-to-create-an-ami-builder-with-aws-codebuild-and-hashicorp-packer-part-2/

Written by AWS Solutions Architects Jason Barto and Heitor Lessa

 
In Part 1 of this post, we described how AWS CodeBuild, AWS CodeCommit, and HashiCorp Packer can be used to build an Amazon Machine Image (AMI) from the latest version of Amazon Linux. In this post, we show how to use AWS CodePipeline, AWS CloudFormation, and Amazon CloudWatch Events to continuously ship new AMIs. We use Ansible by Red Hat to harden the OS on the AMIs through a well-known set of security controls outlined by the Center for Internet Security in its CIS Amazon Linux Benchmark.

You’ll find the source code for this post in our GitHub repo.

At the end of this post, we will have the following architecture:

Requirements

 
To follow along, you will need Git and a text editor. Make sure Git is configured to work with AWS CodeCommit, as described in Part 1.

Technologies

 
In addition to the services and products used in Part 1 of this post, we also use these AWS services and third-party software:

AWS CloudFormation gives developers and systems administrators an easy way to create and manage a collection of related AWS resources, provisioning and updating them in an orderly and predictable fashion.

Amazon CloudWatch Events enables you to react selectively to events in the cloud and in your applications. Specifically, you can create CloudWatch Events rules that match event patterns, and take actions in response to those patterns.

AWS CodePipeline is a continuous integration and continuous delivery service for fast and reliable application and infrastructure updates. AWS CodePipeline builds, tests, and deploys your code every time there is a code change, based on release process models you define.

Amazon SNS is a fast, flexible, fully managed push notification service that lets you send individual messages or to fan out messages to large numbers of recipients. Amazon SNS makes it simple and cost-effective to send push notifications to mobile device users or email recipients. The service can even send messages to other distributed services.

Ansible is a simple IT automation system that handles configuration management, application deployment, cloud provisioning, ad-hoc task-execution, and multinode orchestration.

Getting Started

 
We use CloudFormation to bootstrap the following infrastructure:

Component Purpose
AWS CodeCommit repository Git repository where the AMI builder code is stored.
S3 bucket Build artifact repository used by AWS CodePipeline and AWS CodeBuild.
AWS CodeBuild project Executes the AWS CodeBuild instructions contained in the build specification file.
AWS CodePipeline pipeline Orchestrates the AMI build process, triggered by new changes in the AWS CodeCommit repository.
SNS topic Notifies subscribed email addresses when an AMI build is complete.
CloudWatch Events rule Defines how the AMI builder should send a custom event to notify an SNS topic.
Region AMI Builder Launch Template
N. Virginia (us-east-1)
Ireland (eu-west-1)

After launching the CloudFormation template linked here, we will have a pipeline in the AWS CodePipeline console. (Failed at this stage simply means we don’t have any data in our newly created AWS CodeCommit Git repository.)

Next, we will clone the newly created AWS CodeCommit repository.

If this is your first time connecting to a AWS CodeCommit repository, please see instructions in our documentation on Setup steps for HTTPS Connections to AWS CodeCommit Repositories.

To clone the AWS CodeCommit repository (console)

  1. From the AWS Management Console, open the AWS CloudFormation console.
  2. Choose the AMI-Builder-Blogpost stack, and then choose Output.
  3. Make a note of the Git repository URL.
  4. Use git to clone the repository.

For example: git clone https://git-codecommit.eu-west-1.amazonaws.com/v1/repos/AMI-Builder_repo

To clone the AWS CodeCommit repository (CLI)

# Retrieve CodeCommit repo URL
git_repo=$(aws cloudformation describe-stacks --query 'Stacks[0].Outputs[?OutputKey==`GitRepository`].OutputValue' --output text --stack-name "AMI-Builder-Blogpost")

# Clone repository locally
git clone ${git_repo}

Bootstrap the Repo with the AMI Builder Structure

 
Now that our infrastructure is ready, download all the files and templates required to build the AMI.

Your local Git repo should have the following structure:

.
├── ami_builder_event.json
├── ansible
├── buildspec.yml
├── cloudformation
├── packer_cis.json

Next, push these changes to AWS CodeCommit, and then let AWS CodePipeline orchestrate the creation of the AMI:

git add .
git commit -m "My first AMI"
git push origin master

AWS CodeBuild Implementation Details

 
While we wait for the AMI to be created, let’s see what’s changed in our AWS CodeBuild buildspec.yml file:

...
phases:
  ...
  build:
    commands:
      ...
      - ./packer build -color=false packer_cis.json | tee build.log
  post_build:
    commands:
      - egrep "${AWS_REGION}\:\sami\-" build.log | cut -d' ' -f2 > ami_id.txt
      # Packer doesn't return non-zero status; we must do that if Packer build failed
      - test -s ami_id.txt || exit 1
      - sed -i.bak "s/<<AMI-ID>>/$(cat ami_id.txt)/g" ami_builder_event.json
      - aws events put-events --entries file://ami_builder_event.json
      ...
artifacts:
  files:
    - ami_builder_event.json
    - build.log
  discard-paths: yes

In the build phase, we capture Packer output into a file named build.log. In the post_build phase, we take the following actions:

  1. Look up the AMI ID created by Packer and save its findings to a temporary file (ami_id.txt).
  2. Forcefully make AWS CodeBuild to fail if the AMI ID (ami_id.txt) is not found. This is required because Packer doesn’t fail if something goes wrong during the AMI creation process. We have to tell AWS CodeBuild to stop by informing it that an error occurred.
  3. If an AMI ID is found, we update the ami_builder_event.json file and then notify CloudWatch Events that the AMI creation process is complete.
  4. CloudWatch Events publishes a message to an SNS topic. Anyone subscribed to the topic will be notified in email that an AMI has been created.

Lastly, the new artifacts phase instructs AWS CodeBuild to upload files built during the build process (ami_builder_event.json and build.log) to the S3 bucket specified in the Outputs section of the CloudFormation template. These artifacts can then be used as an input artifact in any later stage in AWS CodePipeline.

For information about customizing the artifacts sequence of the buildspec.yml, see the Build Specification Reference for AWS CodeBuild.

CloudWatch Events Implementation Details

 
CloudWatch Events allow you to extend the AMI builder to not only send email after the AMI has been created, but to hook up any of the supported targets to react to the AMI builder event. This event publication means you can decouple from Packer actions you might take after AMI completion and plug in other actions, as you see fit.

For more information about targets in CloudWatch Events, see the CloudWatch Events API Reference.

In this case, CloudWatch Events should receive the following event, match it with a rule we created through CloudFormation, and publish a message to SNS so that you can receive an email.

Example CloudWatch custom event

[
        {
            "Source": "com.ami.builder",
            "DetailType": "AmiBuilder",
            "Detail": "{ \"AmiStatus\": \"Created\"}",
            "Resources": [ "ami-12cd5guf" ]
        }
]

Cloudwatch Events rule

{
  "detail-type": [
    "AmiBuilder"
  ],
  "source": [
    "com.ami.builder"
  ],
  "detail": {
    "AmiStatus": [
      "Created"
    ]
  }
}

Example SNS message sent in email

{
    "version": "0",
    "id": "f8bdede0-b9d7...",
    "detail-type": "AmiBuilder",
    "source": "com.ami.builder",
    "account": "<<aws_account_number>>",
    "time": "2017-04-28T17:56:40Z",
    "region": "eu-west-1",
    "resources": ["ami-112cd5guf "],
    "detail": {
        "AmiStatus": "Created"
    }
}

Packer Implementation Details

 
In addition to the build specification file, there are differences between the current version of the HashiCorp Packer template (packer_cis.json) and the one used in Part 1.

Variables

  "variables": {
    "vpc": "{{env `BUILD_VPC_ID`}}",
    "subnet": "{{env `BUILD_SUBNET_ID`}}",
         “ami_name”: “Prod-CIS-Latest-AMZN-{{isotime \”02-Jan-06 03_04_05\”}}”
  },
  • ami_name: Prefixes a name used by Packer to tag resources during the Builders sequence.
  • vpc and subnet: Environment variables defined by the CloudFormation stack parameters.

We no longer assume a default VPC is present and instead use the VPC and subnet specified in the CloudFormation parameters. CloudFormation configures the AWS CodeBuild project to use these values as environment variables. They are made available throughout the build process.

That allows for more flexibility should you need to change which VPC and subnet will be used by Packer to launch temporary resources.

Builders

  "builders": [{
    ...
    "ami_name": “{{user `ami_name`| clean_ami_name}}”,
    "tags": {
      "Name": “{{user `ami_name`}}”,
    },
    "run_tags": {
      "Name": “{{user `ami_name`}}",
    },
    "run_volume_tags": {
      "Name": “{{user `ami_name`}}",
    },
    "snapshot_tags": {
      "Name": “{{user `ami_name`}}",
    },
    ...
    "vpc_id": "{{user `vpc` }}",
    "subnet_id": "{{user `subnet` }}"
  }],

We now have new properties (*_tag) and a new function (clean_ami_name) and launch temporary resources in a VPC and subnet specified in the environment variables. AMI names can only contain a certain set of ASCII characters. If the input in project deviates from the expected characters (for example, includes whitespace or slashes), Packer’s clean_ami_name function will fix it.

For more information, see functions on the HashiCorp Packer website.

Provisioners

  "provisioners": [
    {
        "type": "shell",
        "inline": [
            "sudo pip install ansible"
        ]
    }, 
    {
        "type": "ansible-local",
        "playbook_file": "ansible/playbook.yaml",
        "role_paths": [
            "ansible/roles/common"
        ],
        "playbook_dir": "ansible",
        "galaxy_file": "ansible/requirements.yaml"
    },
    {
      "type": "shell",
      "inline": [
        "rm .ssh/authorized_keys ; sudo rm /root/.ssh/authorized_keys"
      ]
    }

We used shell provisioner to apply OS patches in Part 1. Now, we use shell to install Ansible on the target machine and ansible-local to import, install, and execute Ansible roles to make our target machine conform to our standards.

Packer uses shell to remove temporary keys before it creates an AMI from the target and temporary EC2 instance.

Ansible Implementation Details

 
Ansible provides OS patching through a custom Common role that can be easily customized for other tasks.

CIS Benchmark and Cloudwatch Logs are implemented through two Ansible third-party roles that are defined in ansible/requirements.yaml as seen in the Packer template.

The Ansible provisioner uses Ansible Galaxy to download these roles onto the target machine and execute them as instructed by ansible/playbook.yaml.

For information about how these components are organized, see the Playbook Roles and Include Statements in the Ansible documentation.

The following Ansible playbook (ansible</playbook.yaml) controls the execution order and custom properties:

---
- hosts: localhost
  connection: local
  gather_facts: true    # gather OS info that is made available for tasks/roles
  become: yes           # majority of CIS tasks require root
  vars:
    # CIS Controls whitepaper:  http://bit.ly/2mGAmUc
    # AWS CIS Whitepaper:       http://bit.ly/2m2Ovrh
    cis_level_1_exclusions:
    # 3.4.2 and 3.4.3 effectively blocks access to all ports to the machine
    ## This can break automation; ignoring it as there are stronger mechanisms than that
      - 3.4.2 
      - 3.4.3
    # CloudWatch Logs will be used instead of Rsyslog/Syslog-ng
    ## Same would be true if any other software doesn't support Rsyslog/Syslog-ng mechanisms
      - 4.2.1.4
      - 4.2.2.4
      - 4.2.2.5
    # Autofs is not installed in newer versions, let's ignore
      - 1.1.19
    # Cloudwatch Logs role configuration
    logs:
      - file: /var/log/messages
        group_name: "system_logs"
  roles:
    - common
    - anthcourtney.cis-amazon-linux
    - dharrisio.aws-cloudwatch-logs-agent

Both third-party Ansible roles can be easily configured through variables (vars). We use Ansible playbook variables to exclude CIS controls that don’t apply to our case and to instruct the CloudWatch Logs agent to stream the /var/log/messages log file to CloudWatch Logs.

If you need to add more OS or application logs, you can easily duplicate the playbook and make changes. The CloudWatch Logs agent will ship configured log messages to CloudWatch Logs.

For more information about parameters you can use to further customize third-party roles, download Ansible roles for the Cloudwatch Logs Agent and CIS Amazon Linux from the Galaxy website.

Committing Changes

 
Now that Ansible and CloudWatch Events are configured as a part of the build process, commiting any changes to the AWS CodeComit Git Repository will triger a new AMI build process that can be followed through the AWS CodePipeline console.

When the build is complete, an email will be sent to the email address you provided as a part of the CloudFormation stack deployment. The email serves as notification that an AMI has been built and is ready for use.

Summary

 
We used AWS CodeCommit, AWS CodePipeline, AWS CodeBuild, Packer, and Ansible to build a pipeline that continuously builds new, hardened CIS AMIs. We used Amazon SNS so that email addresses subscribed to a SNS topic are notified upon completion of the AMI build.

By treating our AMI creation process as code, we can iterate and track changes over time. In this way, it’s no different from a software development workflow. With that in mind, software patches, OS configuration, and logs that need to be shipped to a central location are only a git commit away.

Next Steps

 
Here are some ideas to extend this AMI builder:

  • Hook up a Lambda function in Cloudwatch Events to update EC2 Auto Scaling configuration upon completion of the AMI build.
  • Use AWS CodePipeline parallel steps to build multiple Packer images.
  • Add a commit ID as a tag for the AMI you created.
  • Create a scheduled Lambda function through Cloudwatch Events to clean up old AMIs based on timestamp (name or additional tag).
  • Implement Windows support for the AMI builder.
  • Create a cross-account or cross-region AMI build.

Cloudwatch Events allow the AMI builder to decouple AMI configuration and creation so that you can easily add your own logic using targets (AWS Lambda, Amazon SQS, Amazon SNS) to add events or recycle EC2 instances with the new AMI.

If you have questions or other feedback, feel free to leave it in the comments or contribute to the AMI Builder repo on GitHub.

Building Loosely Coupled, Scalable, C# Applications with Amazon SQS and Amazon SNS

Post Syndicated from Tara Van Unen original https://aws.amazon.com/blogs/compute/building-loosely-coupled-scalable-c-applications-with-amazon-sqs-and-amazon-sns/

 
Stephen Liedig, Solutions Architect

 

One of the many challenges professional software architects and developers face is how to make cloud-native applications scalable, fault-tolerant, and highly available.

Fundamental to your project success is understanding the importance of making systems highly cohesive and loosely coupled. That means considering the multi-dimensional facets of system coupling to support the distributed nature of the applications that you are building for the cloud.

By that, I mean addressing not only the application-level coupling (managing incoming and outgoing dependencies), but also considering the impacts of of platform, spatial, and temporal coupling of your systems. Platform coupling relates to the interoperability, or lack thereof, of heterogeneous systems components. Spatial coupling deals with managing components at a network topology level or protocol level. Temporal, or runtime coupling, refers to the ability of a component within your system to do any kind of meaningful work while it is performing a synchronous, blocking operation.

The AWS messaging services, Amazon SQS and Amazon SNS, help you deal with these forms of coupling by providing mechanisms for:

  • Reliable, durable, and fault-tolerant delivery of messages between application components
  • Logical decomposition of systems and increased autonomy of components
  • Creating unidirectional, non-blocking operations, temporarily decoupling system components at runtime
  • Decreasing the dependencies that components have on each other through standard communication and network channels

Following on the recent topic, Building Scalable Applications and Microservices: Adding Messaging to Your Toolbox, in this post, I look at some of the ways you can introduce SQS and SNS into your architectures to decouple your components, and show how you can implement them using C#.

Walkthrough

To illustrate some of these concepts, consider a web application that processes customer orders. As good architects and developers, you have followed best practices and made your application scalable and highly available. Your solution included implementing load balancing, dynamic scaling across multiple Availability Zones, and persisting orders in a Multi-AZ Amazon RDS database instance, as in the following diagram.


In this example, the application is responsible for handling and persisting the order data, as well as dealing with increases in traffic for popular items.

One potential point of vulnerability in the order processing workflow is in saving the order in the database. The business expects that every order has been persisted into the database. However, any potential deadlock, race condition, or network issue could cause the persistence of the order to fail. Then, the order is lost with no recourse to restore the order.

With good logging capability, you may be able to identify when an error occurred and which customer’s order failed. This wouldn’t allow you to “restore” the transaction, and by that stage, your customer is no longer your customer.

As illustrated in the following diagram, introducing an SQS queue helps improve your ordering application. Using the queue isolates the processing logic into its own component and runs it in a separate process from the web application. This, in turn, allows the system to be more resilient to spikes in traffic, while allowing work to be performed only as fast as necessary in order to manage costs.


In addition, you now have a mechanism for persisting orders as messages (with the queue acting as a temporary database), and have moved the scope of your transaction with your database further down the stack. In the event of an application exception or transaction failure, this ensures that the order processing can be retired or redirected to the Amazon SQS Dead Letter Queue (DLQ), for re-processing at a later stage. (See the recent post, Using Amazon SQS Dead-Letter Queues to Control Message Failure, for more information on dead-letter queues.)

Scaling the order processing nodes

This change allows you now to scale the web application frontend independently from the processing nodes. The frontend application can continue to scale based on metrics such as CPU usage, or the number of requests hitting the load balancer. Processing nodes can scale based on the number of orders in the queue. Here is an example of scale-in and scale-out alarms that you would associate with the scaling policy.

Scale-out Alarm

aws cloudwatch put-metric-alarm --alarm-name AddCapacityToCustomerOrderQueue --metric-name ApproximateNumberOfMessagesVisible --namespace "AWS/SQS" 
--statistic Average --period 300 --threshold 3 --comparison-operator GreaterThanOrEqualToThreshold --dimensions Name=QueueName,Value=customer-orders
--evaluation-periods 2 --alarm-actions <arn of the scale-out autoscaling policy>

Scale-in Alarm

aws cloudwatch put-metric-alarm --alarm-name RemoveCapacityFromCustomerOrderQueue --metric-name ApproximateNumberOfMessagesVisible --namespace "AWS/SQS" 
 --statistic Average --period 300 --threshold 1 --comparison-operator LessThanOrEqualToThreshold --dimensions Name=QueueName,Value=customer-orders
 --evaluation-periods 2 --alarm-actions <arn of the scale-in autoscaling policy>

In the above example, use the ApproximateNumberOfMessagesVisible metric to discover the queue length and drive the scaling policy of the Auto Scaling group. Another useful metric is ApproximateAgeOfOldestMessage, when applications have time-sensitive messages and developers need to ensure that messages are processed within a specific time period.

Scaling the order processing implementation

On top of scaling at an infrastructure level using Auto Scaling, make sure to take advantage of the processing power of your Amazon EC2 instances by using as many of the available threads as possible. There are several ways to implement this. In this post, we build a Windows service that uses the BackgroundWorker class to process the messages from the queue.

Here’s a closer look at the implementation. In the first section of the consuming application, use a loop to continually poll the queue for new messages, and construct a ReceiveMessageRequest variable.

public static void PollQueue()
{
    while (_running)
    {
        Task<ReceiveMessageResponse> receiveMessageResponse;

        // Pull messages off the queue
        using (var sqs = new AmazonSQSClient())
        {
            const int maxMessages = 10;  // 1-10

            //Receiving a message
            var receiveMessageRequest = new ReceiveMessageRequest
            {
                // Get URL from Configuration
                QueueUrl = _queueUrl, 
                // The maximum number of messages to return. 
                // Fewer messages might be returned. 
                MaxNumberOfMessages = maxMessages, 
                // A list of attributes that need to be returned with message.
                AttributeNames = new List<string> { "All" },
                // Enable long polling. 
                // Time to wait for message to arrive on queue.
                WaitTimeSeconds = 5 
            };

            receiveMessageResponse = sqs.ReceiveMessageAsync(receiveMessageRequest);
        }

The WaitTimeSeconds property of the ReceiveMessageRequest specifies the duration (in seconds) that the call waits for a message to arrive in the queue before returning a response to the calling application. There are a few benefits to using long polling:

  • It reduces the number of empty responses by allowing SQS to wait until a message is available in the queue before sending a response.
  • It eliminates false empty responses by querying all (rather than a limited number) of the servers.
  • It returns messages as soon any message becomes available.

For more information, see Amazon SQS Long Polling.

After you have returned messages from the queue, you can start to process them by looping through each message in the response and invoking a new BackgroundWorker thread.

// Process messages
if (receiveMessageResponse.Result.Messages != null)
{
    foreach (var message in receiveMessageResponse.Result.Messages)
    {
        Console.WriteLine("Received SQS message, starting worker thread");

        // Create background worker to process message
        BackgroundWorker worker = new BackgroundWorker();
        worker.DoWork += (obj, e) => ProcessMessage(message);
        worker.RunWorkerAsync();
    }
}
else
{
    Console.WriteLine("No messages on queue");
}

The event handler, ProcessMessage, is where you implement business logic for processing orders. It is important to have a good understanding of how long a typical transaction takes so you can set a message VisibilityTimeout that is long enough to complete your operation. If order processing takes longer than the specified timeout period, the message becomes visible on the queue. Other nodes may pick it and process the same order twice, leading to unintended consequences.

Handling Duplicate Messages

In order to manage duplicate messages, seek to make your processing application idempotent. In mathematics, idempotent describes a function that produces the same result if it is applied to itself:

f(x) = f(f(x))

No matter how many times you process the same message, the end result is the same (definition from Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions, Hohpe and Wolf, 2004).

There are several strategies you could apply to achieve this:

  • Create messages that have inherent idempotent characteristics. That is, they are non-transactional in nature and are unique at a specified point in time. Rather than saying “place new order for Customer A,” which adds a duplicate order to the customer, use “place order <orderid> on <timestamp> for Customer A,” which creates a single order no matter how often it is persisted.
  • Deliver your messages via an Amazon SQS FIFO queue, which provides the benefits of message sequencing, but also mechanisms for content-based deduplication. You can deduplicate using the MessageDeduplicationId property on the SendMessage request or by enabling content-based deduplication on the queue, which generates a hash for MessageDeduplicationId, based on the content of the message, not the attributes.
var sendMessageRequest = new SendMessageRequest
{
    QueueUrl = _queueUrl,
    MessageBody = JsonConvert.SerializeObject(order),
    MessageGroupId = Guid.NewGuid().ToString("N"),
    MessageDeduplicationId = Guid.NewGuid().ToString("N")
};
  • If using SQS FIFO queues is not an option, keep a message log of all messages attributes processed for a specified period of time, as an alternative to message deduplication on the receiving end. Verifying the existence of the message in the log before processing the message adds additional computational overhead to your processing. This can be minimized through low latency persistence solutions such as Amazon DynamoDB. Bear in mind that this solution is dependent on the successful, distributed transaction of the message and the message log.

Handling exceptions

Because of the distributed nature of SQS queues, it does not automatically delete the message. Therefore, you must explicitly delete the message from the queue after processing it, using the message ReceiptHandle property (see the following code example).

However, if at any stage you have an exception, avoid handling it as you normally would. The intention is to make sure that the message ends back on the queue, so that you can gracefully deal with intermittent failures. Instead, log the exception to capture diagnostic information, and swallow it.

By not explicitly deleting the message from the queue, you can take advantage of the VisibilityTimeout behavior described earlier. Gracefully handle the message processing failure and make the unprocessed message available to other nodes to process.

In the event that subsequent retries fail, SQS automatically moves the message to the configured DLQ after the configured number of receives has been reached. You can further investigate why the order process failed. Most importantly, the order has not been lost, and your customer is still your customer.

private static void ProcessMessage(Message message)
{
    using (var sqs = new AmazonSQSClient())
    {
        try
        {
            Console.WriteLine("Processing message id: {0}", message.MessageId);

            // Implement messaging processing here
            // Ensure no downstream resource contention (parallel processing)
            // <your order processing logic in here…>
            Console.WriteLine("{0} Thread {1}: {2}", DateTime.Now.ToString("s"), Thread.CurrentThread.ManagedThreadId, message.MessageId);
            
            // Delete the message off the queue. 
            // Receipt handle is the identifier you must provide 
            // when deleting the message.
            var deleteRequest = new DeleteMessageRequest(_queueName, message.ReceiptHandle);
            sqs.DeleteMessageAsync(deleteRequest);
            Console.WriteLine("Processed message id: {0}", message.MessageId);

        }
        catch (Exception ex)
        {
            // Do nothing.
            // Swallow exception, message will return to the queue when 
            // visibility timeout has been exceeded.
            Console.WriteLine("Could not process message due to error. Exception: {0}", ex.Message);
        }
    }
}

Using SQS to adapt to changing business requirements

One of the benefits of introducing a message queue is that you can accommodate new business requirements without dramatically affecting your application.

If, for example, the business decided that all orders placed over $5000 are to be handled as a priority, you could introduce a new “priority order” queue. The way the orders are processed does not change. The only significant change to the processing application is to ensure that messages from the “priority order” queue are processed before the “standard order” queue.

The following diagram shows how this logic could be isolated in an “order dispatcher,” whose only purpose is to route order messages to the appropriate queue based on whether the order exceeds $5000. Nothing on the web application or the processing nodes changes other than the target queue to which the order is sent. The rates at which orders are processed can be achieved by modifying the poll rates and scalability settings that I have already discussed.

Extending the design pattern with Amazon SNS

Amazon SNS supports reliable publish-subscribe (pub-sub) scenarios and push notifications to known endpoints across a wide variety of protocols. It eliminates the need to periodically check or poll for new information and updates. SNS supports:

  • Reliable storage of messages for immediate or delayed processing
  • Publish / subscribe – direct, broadcast, targeted “push” messaging
  • Multiple subscriber protocols
  • Amazon SQS, HTTP, HTTPS, email, SMS, mobile push, AWS Lambda

With these capabilities, you can provide parallel asynchronous processing of orders in the system and extend it to support any number of different business use cases without affecting the production environment. This is commonly referred to as a “fanout” scenario.

Rather than your web application pushing orders to a queue for processing, send a notification via SNS. The SNS messages are sent to a topic and then replicated and pushed to multiple SQS queues and Lambda functions for processing.

As the diagram above shows, you have the development team consuming “live” data as they work on the next version of the processing application, or potentially using the messages to troubleshoot issues in production.

Marketing is consuming all order information, via a Lambda function that has subscribed to the SNS topic, inserting the records into an Amazon Redshift warehouse for analysis.

All of this, of course, is happening without affecting your order processing application.

Summary

While I haven’t dived deep into the specifics of each service, I have discussed how these services can be applied at an architectural level to build loosely coupled systems that facilitate multiple business use cases. I’ve also shown you how to use infrastructure and application-level scaling techniques, so you can get the most out of your EC2 instances.

One of the many benefits of using these managed services is how quickly and easily you can implement powerful messaging capabilities in your systems, and lower the capital and operational costs of managing your own messaging middleware.

Using Amazon SQS and Amazon SNS together can provide you with a powerful mechanism for decoupling application components. This should be part of design considerations as you architect for the cloud.

For more information, see the Amazon SQS Developer Guide and Amazon SNS Developer Guide. You’ll find tutorials on all the concepts covered in this post, and more. To can get started using the AWS console or SDK of your choice visit:

Happy messaging!