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Federate Database User Authentication Easily with IAM and Amazon Redshift

Post Syndicated from Thiyagarajan Arumugam original https://aws.amazon.com/blogs/big-data/federate-database-user-authentication-easily-with-iam-and-amazon-redshift/

Managing database users though federation allows you to manage authentication and authorization procedures centrally. Amazon Redshift now supports database authentication with IAM, enabling user authentication though enterprise federation. No need to manage separate database users and passwords to further ease the database administration. You can now manage users outside of AWS and authenticate them for access to an Amazon Redshift data warehouse. Do this by integrating IAM authentication and a third-party SAML-2.0 identity provider (IdP), such as AD FS, PingFederate, or Okta. In addition, database users can also be automatically created at their first login based on corporate permissions.

In this post, I demonstrate how you can extend the federation to enable single sign-on (SSO) to the Amazon Redshift data warehouse.

SAML and Amazon Redshift

AWS supports Security Assertion Markup Language (SAML) 2.0, which is an open standard for identity federation used by many IdPs. SAML enables federated SSO, which enables your users to sign in to the AWS Management Console. Users can also make programmatic calls to AWS API actions by using assertions from a SAML-compliant IdP. For example, if you use Microsoft Active Directory for corporate directories, you may be familiar with how Active Directory and AD FS work together to enable federation. For more information, see the Enabling Federation to AWS Using Windows Active Directory, AD FS, and SAML 2.0 AWS Security Blog post.

Amazon Redshift now provides the GetClusterCredentials API operation that allows you to generate temporary database user credentials for authentication. You can set up an IAM permissions policy that generates these credentials for connecting to Amazon Redshift. Extending the IAM authentication, you can configure the federation of AWS access though a SAML 2.0–compliant IdP. An IAM role can be configured to permit the federated users call the GetClusterCredentials action and generate temporary credentials to log in to Amazon Redshift databases. You can also set up policies to restrict access to Amazon Redshift clusters, databases, database user names, and user group.

Amazon Redshift federation workflow

In this post, I demonstrate how you can use a JDBC– or ODBC-based SQL client to log in to the Amazon Redshift cluster using this feature. The SQL clients used with Amazon Redshift JDBC or ODBC drivers automatically manage the process of calling the GetClusterCredentials action, retrieving the database user credentials, and establishing a connection to your Amazon Redshift database. You can also use your database application to programmatically call the GetClusterCredentials action, retrieve database user credentials, and connect to the database. I demonstrate these features using an example company to show how different database users accounts can be managed easily using federation.

The following diagram shows how the SSO process works:

  1. JDBC/ODBC
  2. Authenticate using Corp Username/Password
  3. IdP sends SAML assertion
  4. Call STS to assume role with SAML
  5. STS Returns Temp Credentials
  6. Use Temp Credentials to get Temp cluster credentials
  7. Connect to Amazon Redshift using temp credentials

Walkthrough

Example Corp. is using Active Directory (idp host:demo.examplecorp.com) to manage federated access for users in its organization. It has an AWS account: 123456789012 and currently manages an Amazon Redshift cluster with the cluster ID “examplecorp-dw”, database “analytics” in us-west-2 region for its Sales and Data Science teams. It wants the following access:

  • Sales users can access the examplecorp-dw cluster using the sales_grp database group
  • Sales users access examplecorp-dw through a JDBC-based SQL client
  • Sales users access examplecorp-dw through an ODBC connection, for their reporting tools
  • Data Science users access the examplecorp-dw cluster using the data_science_grp database group.
  • Partners access the examplecorp-dw cluster and query using the partner_grp database group.
  • Partners are not federated through Active Directory and are provided with separate IAM user credentials (with IAM user name examplecorpsalespartner).
  • Partners can connect to the examplecorp-dw cluster programmatically, using language such as Python.
  • All users are automatically created in Amazon Redshift when they log in for the first time.
  • (Optional) Internal users do not specify database user or group information in their connection string. It is automatically assigned.
  • Data warehouse users can use SSO for the Amazon Redshift data warehouse using the preceding permissions.

Step 1:  Set up IdPs and federation

The Enabling Federation to AWS Using Windows Active Directory post demonstrated how to prepare Active Directory and enable federation to AWS. Using those instructions, you can establish trust between your AWS account and the IdP and enable user access to AWS using SSO.  For more information, see Identity Providers and Federation.

For this walkthrough, assume that this company has already configured SSO to their AWS account: 123456789012 for their Active Directory domain demo.examplecorp.com. The Sales and Data Science teams are not required to specify database user and group information in the connection string. The connection string can be configured by adding SAML Attribute elements to your IdP. Configuring these optional attributes enables internal users to conveniently avoid providing the DbUser and DbGroup parameters when they log in to Amazon Redshift.

The user-name attribute can be set up as follows, with a user ID (for example, nancy) or an email address (for example. [email protected]):

<Attribute Name="https://redshift.amazon.com/SAML/Attributes/DbUser">  
  <AttributeValue>user-name</AttributeValue>
</Attribute>

The AutoCreate attribute can be defined as follows:

<Attribute Name="https://redshift.amazon.com/SAML/Attributes/AutoCreate">
    <AttributeValue>true</AttributeValue>
</Attribute>

The sales_grp database group can be included as follows:

<Attribute Name="https://redshift.amazon.com/SAML/Attributes/DbGroups">
    <AttributeValue>sales_grp</AttributeValue>
</Attribute>

For more information about attribute element configuration, see Configure SAML Assertions for Your IdP.

Step 2: Create IAM roles for access to the Amazon Redshift cluster

The next step is to create IAM policies with permissions to call GetClusterCredentials and provide authorization for Amazon Redshift resources. To grant a SQL client the ability to retrieve the cluster endpoint, region, and port automatically, include the redshift:DescribeClusters action with the Amazon Redshift cluster resource in the IAM role.  For example, users can connect to the Amazon Redshift cluster using a JDBC URL without the need to hardcode the Amazon Redshift endpoint:

Previous:  jdbc:redshift://endpoint:port/database

Current:  jdbc:redshift:iam://clustername:region/dbname

Use IAM to create the following policies. You can also use an existing user or role and assign these policies. For example, if you already created an IAM role for IdP access, you can attach the necessary policies to that role. Here is the policy created for sales users for this example:

Sales_DW_IAM_Policy

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "redshift:DescribeClusters"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:GetClusterCredentials"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw",
                "arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
            ],
            "Condition": {
                "StringEquals": {
                    "aws:userid": "AIDIODR4TAW7CSEXAMPLE:${redshift:DbUser}@examplecorp.com"
                }
            }
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:CreateClusterUser"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:JoinGroup"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:dbgroup:examplecorp-dw/sales_grp"
            ]
        }
    ]
}

The policy uses the following parameter values:

  • Region: us-west-2
  • AWS Account: 123456789012
  • Cluster name: examplecorp-dw
  • Database group: sales_grp
  • IAM role: AIDIODR4TAW7CSEXAMPLE
Policy Statement Description
{
"Effect":"Allow",
"Action":[
"redshift:DescribeClusters"
],
"Resource":[
"arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw"
]
}

Allow users to retrieve the cluster endpoint, region, and port automatically for the Amazon Redshift cluster examplecorp-dw. This specification uses the resource format arn:aws:redshift:region:account-id:cluster:clustername. For example, the SQL client JDBC can be specified in the format jdbc:redshift:iam://clustername:region/dbname.

For more information, see Amazon Resource Names.

{
"Effect":"Allow",
"Action":[
"redshift:GetClusterCredentials"
],
"Resource":[
"arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw",
"arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
],
"Condition":{
"StringEquals":{
"aws:userid":"AIDIODR4TAW7CSEXAMPLE:${redshift:DbUser}@examplecorp.com"
}
}
}

Generates a temporary token to authenticate into the examplecorp-dw cluster. “arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}” restricts the corporate user name to the database user name for that user. This resource is specified using the format: arn:aws:redshift:region:account-id:dbuser:clustername/dbusername.

The Condition block enforces that the AWS user ID should match “AIDIODR4TAW7CSEXAMPLE:${redshift:DbUser}@examplecorp.com”, so that individual users can authenticate only as themselves. The AIDIODR4TAW7CSEXAMPLE role has the Sales_DW_IAM_Policy policy attached.

{
"Effect":"Allow",
"Action":[
"redshift:CreateClusterUser"
],
"Resource":[
"arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
]
}
Automatically creates database users in examplecorp-dw, when they log in for the first time. Subsequent logins reuse the existing database user.
{
"Effect":"Allow",
"Action":[
"redshift:JoinGroup"
],
"Resource":[
"arn:aws:redshift:us-west-2:123456789012:dbgroup:examplecorp-dw/sales_grp"
]
}
Allows sales users to join the sales_grp database group through the resource “arn:aws:redshift:us-west-2:123456789012:dbgroup:examplecorp-dw/sales_grp” that is specified in the format arn:aws:redshift:region:account-id:dbgroup:clustername/dbgroupname.

Similar policies can be created for Data Science users with access to join the data_science_grp group in examplecorp-dw. You can now attach the Sales_DW_IAM_Policy policy to the role that is mapped to IdP application for SSO.
 For more information about how to define the claim rules, see Configuring SAML Assertions for the Authentication Response.

Because partners are not authorized using Active Directory, they are provided with IAM credentials and added to the partner_grp database group. The Partner_DW_IAM_Policy is attached to the IAM users for partners. The following policy allows partners to log in using the IAM user name as the database user name.

Partner_DW_IAM_Policy

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "redshift:DescribeClusters"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:GetClusterCredentials"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:cluster:examplecorp-dw",
                "arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
            ],
            "Condition": {
                "StringEquals": {
                    "redshift:DbUser": "${aws:username}"
                }
            }
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:CreateClusterUser"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:dbuser:examplecorp-dw/${redshift:DbUser}"
            ]
        },
        {
            "Effect": "Allow",
            "Action": [
                "redshift:JoinGroup"
            ],
            "Resource": [
                "arn:aws:redshift:us-west-2:123456789012:dbgroup:examplecorp-dw/partner_grp"
            ]
        }
    ]
}

redshift:DbUser“: “${aws:username}” forces an IAM user to use the IAM user name as the database user name.

With the previous steps configured, you can now establish the connection to Amazon Redshift through JDBC– or ODBC-supported clients.

Step 3: Set up database user access

Before you start connecting to Amazon Redshift using the SQL client, set up the database groups for appropriate data access. Log in to your Amazon Redshift database as superuser to create a database group, using CREATE GROUP.

Log in to examplecorp-dw/analytics as superuser and create the following groups and users:

CREATE GROUP sales_grp;
CREATE GROUP datascience_grp;
CREATE GROUP partner_grp;

Use the GRANT command to define access permissions to database objects (tables/views) for the preceding groups.

Step 4: Connect to Amazon Redshift using the JDBC SQL client

Assume that sales user “nancy” is using the SQL Workbench client and JDBC driver to log in to the Amazon Redshift data warehouse. The following steps help set up the client and establish the connection:

  1. Download the latest Amazon Redshift JDBC driver from the Configure a JDBC Connection page
  2. Build the JDBC URL with the IAM option in the following format:
    jdbc:redshift:iam://examplecorp-dw:us-west-2/sales_db

Because the redshift:DescribeClusters action is assigned to the preceding IAM roles, it automatically resolves the cluster endpoints and the port. Otherwise, you can specify the endpoint and port information in the JDBC URL, as described in Configure a JDBC Connection.

Identify the following JDBC options for providing the IAM credentials (see the “Prepare your environment” section) and configure in the SQL Workbench Connection Profile:

plugin_name=com.amazon.redshift.plugin.AdfsCredentialsProvider 
idp_host=demo.examplecorp.com (The name of the corporate identity provider host)
idp_port=443  (The port of the corporate identity provider host)
user=examplecorp\nancy(corporate user name)
password=***(corporate user password)

The SQL workbench configuration looks similar to the following screenshot:

Now, “nancy” can connect to examplecorp-dw by authenticating using the corporate Active Directory. Because the SAML attributes elements are already configured for nancy, she logs in as database user nancy and is assigned the sales_grp. Similarly, other Sales and Data Science users can connect to the examplecorp-dw cluster. A custom Amazon Redshift ODBC driver can also be used to connect using a SQL client. For more information, see Configure an ODBC Connection.

Step 5: Connecting to Amazon Redshift using JDBC SQL Client and IAM Credentials

This optional step is necessary only when you want to enable users that are not authenticated with Active Directory. Partners are provided with IAM credentials that they can use to connect to the examplecorp-dw Amazon Redshift clusters. These IAM users are attached to Partner_DW_IAM_Policy that assigns them to be assigned to the public database group in Amazon Redshift. The following JDBC URLs enable them to connect to the Amazon Redshift cluster:

jdbc:redshift:iam//examplecorp-dw/analytics?AccessKeyID=XXX&SecretAccessKey=YYY&DbUser=examplecorpsalespartner&DbGroup= partner_grp&AutoCreate=true

The AutoCreate option automatically creates a new database user the first time the partner logs in. There are several other options available to conveniently specify the IAM user credentials. For more information, see Options for providing IAM credentials.

Step 6: Connecting to Amazon Redshift using an ODBC client for Microsoft Windows

Assume that another sales user “uma” is using an ODBC-based client to log in to the Amazon Redshift data warehouse using Example Corp Active Directory. The following steps help set up the ODBC client and establish the Amazon Redshift connection in a Microsoft Windows operating system connected to your corporate network:

  1. Download and install the latest Amazon Redshift ODBC driver.
  2. Create a system DSN entry.
    1. In the Start menu, locate the driver folder or folders:
      • Amazon Redshift ODBC Driver (32-bit)
      • Amazon Redshift ODBC Driver (64-bit)
      • If you installed both drivers, you have a folder for each driver.
    2. Choose ODBC Administrator, and then type your administrator credentials.
    3. To configure the driver for all users on the computer, choose System DSN. To configure the driver for your user account only, choose User DSN.
    4. Choose Add.
  3. Select the Amazon Redshift ODBC driver, and choose Finish. Configure the following attributes:
    Data Source Name =any friendly name to identify the ODBC connection 
    Database=analytics
    user=uma(corporate user name)
    Auth Type-Identity Provider: AD FS
    password=leave blank (Windows automatically authenticates)
    Cluster ID: examplecorp-dw
    idp_host=demo.examplecorp.com (The name of the corporate IdP host)

This configuration looks like the following:

  1. Choose OK to save the ODBC connection.
  2. Verify that uma is set up with the SAML attributes, as described in the “Set up IdPs and federation” section.

The user uma can now use this ODBC connection to establish the connection to the Amazon Redshift cluster using any ODBC-based tools or reporting tools such as Tableau. Internally, uma authenticates using the Sales_DW_IAM_Policy  IAM role and is assigned the sales_grp database group.

Step 7: Connecting to Amazon Redshift using Python and IAM credentials

To enable partners, connect to the examplecorp-dw cluster programmatically, using Python on a computer such as Amazon EC2 instance. Reuse the IAM users that are attached to the Partner_DW_IAM_Policy policy defined in Step 2.

The following steps show this set up on an EC2 instance:

  1. Launch a new EC2 instance with the Partner_DW_IAM_Policy role, as described in Using an IAM Role to Grant Permissions to Applications Running on Amazon EC2 Instances. Alternatively, you can attach an existing IAM role to an EC2 instance.
  2. This example uses Python PostgreSQL Driver (PyGreSQL) to connect to your Amazon Redshift clusters. To install PyGreSQL on Amazon Linux, use the following command as the ec2-user:
    sudo easy_install pip
    sudo yum install postgresql postgresql-devel gcc python-devel
    sudo pip install PyGreSQL

  1. The following code snippet demonstrates programmatic access to Amazon Redshift for partner users:
    #!/usr/bin/env python
    """
    Usage:
    python redshift-unload-copy.py <config file> <region>
    
    * Copyright 2014, Amazon.com, Inc. or its affiliates. All Rights Reserved.
    *
    * Licensed under the Amazon Software License (the "License").
    * You may not use this file except in compliance with the License.
    * A copy of the License is located at
    *
    * http://aws.amazon.com/asl/
    *
    * or in the "license" file accompanying this file. This file is distributed
    * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
    * express or implied. See the License for the specific language governing
    * permissions and limitations under the License.
    """
    
    import sys
    import pg
    import boto3
    
    REGION = 'us-west-2'
    CLUSTER_IDENTIFIER = 'examplecorp-dw'
    DB_NAME = 'sales_db'
    DB_USER = 'examplecorpsalespartner'
    
    options = """keepalives=1 keepalives_idle=200 keepalives_interval=200
                 keepalives_count=6"""
    
    set_timeout_stmt = "set statement_timeout = 1200000"
    
    def conn_to_rs(host, port, db, usr, pwd, opt=options, timeout=set_timeout_stmt):
        rs_conn_string = """host=%s port=%s dbname=%s user=%s password=%s
                             %s""" % (host, port, db, usr, pwd, opt)
        print "Connecting to %s:%s:%s as %s" % (host, port, db, usr)
        rs_conn = pg.connect(dbname=rs_conn_string)
        rs_conn.query(timeout)
        return rs_conn
    
    def main():
        # describe the cluster and fetch the IAM temporary credentials
        global redshift_client
        redshift_client = boto3.client('redshift', region_name=REGION)
        response_cluster_details = redshift_client.describe_clusters(ClusterIdentifier=CLUSTER_IDENTIFIER)
        response_credentials = redshift_client.get_cluster_credentials(DbUser=DB_USER,DbName=DB_NAME,ClusterIdentifier=CLUSTER_IDENTIFIER,DurationSeconds=3600)
        rs_host = response_cluster_details['Clusters'][0]['Endpoint']['Address']
        rs_port = response_cluster_details['Clusters'][0]['Endpoint']['Port']
        rs_db = DB_NAME
        rs_iam_user = response_credentials['DbUser']
        rs_iam_pwd = response_credentials['DbPassword']
        # connect to the Amazon Redshift cluster
        conn = conn_to_rs(rs_host, rs_port, rs_db, rs_iam_user,rs_iam_pwd)
        # execute a query
        result = conn.query("SELECT sysdate as dt")
        # fetch results from the query
        for dt_val in result.getresult() :
            print dt_val
        # close the Amazon Redshift connection
        conn.close()
    
    if __name__ == "__main__":
        main()

You can save this Python program in a file (redshiftscript.py) and execute it at the command line as ec2-user:

python redshiftscript.py

Now partners can connect to the Amazon Redshift cluster using the Python script, and authentication is federated through the IAM user.

Summary

In this post, I demonstrated how to use federated access using Active Directory and IAM roles to enable single sign-on to an Amazon Redshift cluster. I also showed how partners outside an organization can be managed easily using IAM credentials.  Using the GetClusterCredentials API action, now supported by Amazon Redshift, lets you manage a large number of database users and have them use corporate credentials to log in. You don’t have to maintain separate database user accounts.

Although this post demonstrated the integration of IAM with AD FS and Active Directory, you can replicate this solution across with your choice of SAML 2.0 third-party identity providers (IdP), such as PingFederate or Okta. For the different supported federation options, see Configure SAML Assertions for Your IdP.

If you have questions or suggestions, please comment below.


Additional Reading

Learn how to establish federated access to your AWS resources by using Active Directory user attributes.


About the Author

Thiyagarajan Arumugam is a Big Data Solutions Architect at Amazon Web Services and designs customer architectures to process data at scale. Prior to AWS, he built data warehouse solutions at Amazon.com. In his free time, he enjoys all outdoor sports and practices the Indian classical drum mridangam.

 

Spaghetti Download – Web Application Security Scanner

Post Syndicated from Darknet original https://www.darknet.org.uk/2017/10/spaghetti-download-web-application-security-scanner/?utm_source=rss&utm_medium=social&utm_campaign=darknetfeed

Spaghetti Download – Web Application Security Scanner

Spaghetti is an Open-source Web Application Security Scanner, it is designed to find various default and insecure files, configurations, and misconfigurations.

It is built on Python 2.7 and can run on any platform which has a Python environment.

Features of Spaghetti Web Application Security Scanner

  • Fingerprints
    • Server
    • Web Frameworks (CakePHP, CherryPy,…)
    • Web Application Firewall (Waf)
    • Content Management System (CMS)
    • Operating System (Linux, Unix,..)
    • Language (PHP, Ruby,…)
    • Cookie Security
  • Bruteforce
    • Admin Interface
    • Common Backdoors
    • Common Backup Directory
    • Common Backup File
    • Common Directory
    • Common File
    • Log File
  • Disclosure
    • Emails
    • Private IP
    • Credit Cards
  • Attacks
    • HTML Injection
    • SQL Injection
    • LDAP Injection
    • XPath Injection
    • Cross Site Scripting (XSS)
    • Remote File Inclusion (RFI)
    • PHP Code Injection
  • Other
    • HTTP Allow Methods
    • HTML Object
    • Multiple Index
    • Robots Paths
    • Web Dav
    • Cross Site Tracing (XST)
    • PHPINFO
    • .Listing
  • Vulns
    • ShellShock
    • Anonymous Cipher (CVE-2007-1858)
    • Crime (SPDY) (CVE-2012-4929)
    • Struts-Shock

Using Spaghetti Web Application Security Scanner

[email protected]:~/Spaghetti# python spaghetti.py
_____ _ _ _ _
| __|___ ___ ___| |_ ___| |_| |_|_|
|__ | .

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Sean Hodgins’ Haunted Jack in the Box

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/sean-hodgins-haunted-jack-box/

After making a delightful Bitcoin lottery using a Raspberry Pi, Sean Hodgins brings us more Pi-powered goodness in time for every maker’s favourite holiday: Easter! Just kidding, it’s Halloween. Check out his hair-raising new build, the Haunted Jack in the Box.

Haunted Jack in the Box – DIY Raspberry Pi Project

This project uses a raspberry pi and face detection using the pi camera to determine when someone is looking at it. Plenty of opportunities to scare people with it. You can make your own!

Haunted jack-in-the-box?

Imagine yourself wandering around a dimly lit house. Your eyes idly scan a shelf. Suddenly, out of nowhere, a twangy melody! What was that? You take a closer look…there seems to be a box in jolly colours…with a handle that’s spinning by itself?!

Sidling up to Sean Hodgins' Haunted Jack in the Box

What’s…going on?

You freeze, unable to peel your eyes away, and BAM!, out pops a maniacally grinning clown. You promptly pee yourself. Happy Halloween, courtesy of Sean Hodgins.

Clip of Sean Hodgins' Haunted Jack in the Box

Eerie disembodied voice: You’re welco-o-o-ome!

How has Sean built this?

Sean purchased a jack-in-the-box toy and replaced its bottom side with one that would hold the necessary electronic components. He 3D-printed this part, but says you could also just build it by hand.

The bottom of the box houses a Raspberry Pi 3 Model B and a servomotor which can turn the windup handle. There’s also a magnetic reed switch which helps the Pi decide when to trigger the Jack. Sean hooked up the components to the Pi’s GPIO pins, and used an elastic band as a drive belt to connect the pulleys on the motor and the handle.

Film clip showing the inside of Sean Hodgin's Haunted Jack in the Box

Sean explains that he has used a lot of double-sided tape and superglue in this build. The bottom and top are held together with two screws, because, as he describes it, “the Jack coming out is a little violent.”

In addition to his video walk-through, he provides build instructions on Instructables, Hackaday, Hackster, and Imgur — pick your poison. And be sure to subscribe to Sean’s YouTube channel to see what he comes up with next.

Wait, how does the haunted part work?

But if I explain it, it won’t be scary anymore! OK, fiiiine.

With the help of a a Camera Module and OpenCV, Sean implemented facial recognition: Jack knows when someone is looking at his box, and responds by winding up and popping out.

View of command line output of the Python script for Sean Hodgins' Haunted Jack in the Box

Testing the haunting script

Sean’s Python script is available here, but as he points out, there are many ways in which you could adapt this code, and the build itself, to be even more frightening.

So very haunted

What would you do with this build? Add creepy laughter? Soundbites from It? Lighting effects? Maybe even infrared light and a NoIR Camera Module, so that you can scare people in total darkness? There are so many possibilities for this project — tell us your idea in the comments.

The post Sean Hodgins’ Haunted Jack in the Box appeared first on Raspberry Pi.

A2SV – Auto Scanning SSL Vulnerability Tool For Poodle & Heartbleed

Post Syndicated from Darknet original https://www.darknet.org.uk/2017/10/a2sv-auto-scanning-ssl-vulnerability-tool-poodle-heartbleed/?utm_source=rss&utm_medium=social&utm_campaign=darknetfeed

A2SV – Auto Scanning SSL Vulnerability Tool For Poodle & Heartbleed

A2SV is a Python-based SSL Vulnerability focused tool that allows for auto-scanning and detection of the common and well-known SSL Vulnerabilities.

SSL Vulnerabilities Detected by A2SV

  • [CVE-2007-1858] Anonymous Cipher
  • [CVE-2012-4929] CRIME(SPDY)
  • [CVE-2014-0160] CCS Injection
  • [CVE-2014-0224] HeartBleed
  • [CVE-2014-3566] SSLv3 POODLE
  • [CVE-2015-0204] FREAK Attack
  • [CVE-2015-4000] LOGJAM Attack
  • [CVE-2016-0800] SSLv2 DROWN

Planned for future:

  • [PLAN] SSL ACCF
  • [PLAN] SSL Information Analysis

Installation & Requirements for A2SV

A.

Read the rest of A2SV – Auto Scanning SSL Vulnerability Tool For Poodle & Heartbleed now! Only available at Darknet.

Low-tech Raspberry Pi robot

Post Syndicated from Rachel Churcher original https://www.raspberrypi.org/blog/low-tech-raspberry-pi-robot/

Robot-builder extraordinaire Clément Didier is ushering in the era of our cybernetic overlords. Future generations will remember him as the creator of robots constructed from cardboard and conductive paint which are so easy to replicate that a robot could do it. Welcome to the singularity.

Bare Conductive on Twitter

This cool robot was made with the #PiCap, conductive paint and @Raspberry_Pi by @clementdidier. Full tutorial: https://t.co/AcQVTS4vr2 https://t.co/D04U5UGR0P

Simple interface

To assemble the robot, Clément made use of a Pi Cap board, a motor driver, and most importantly, a tube of Bare Conductive Electric Paint. He painted the control interface onto the cardboard surface of the robot, allowing a human, replicant, or superior robot to direct its movements simply by touching the paint.

Clever design

The Raspberry Pi 3, the motor control board, and the painted input buttons interface via the GPIO breakout pins on the Pi Cap. Crocodile clips connect the Pi Cap to the cardboard-and-paint control surface, while jumper wires connect it to the motor control board.

Raspberry Pi and bare conductive Pi Cap

Sing with me: ‘The Raspberry Pi’s connected to the Pi Cap, and the Pi Cap’s connected to the inputs, and…’

Two battery packs provide power to the Raspberry Pi, and to the four independently driven motors. Software, written in Python, allows the robot to respond to inputs from the conductive paint. The motors drive wheels attached to a plastic chassis, moving and turning the robot at the touch of a square of black paint.

Artistic circuit

Clément used masking tape and a paintbrush to create the control buttons. For a human, this is obviously a fiddly process which relies on the blocking properties of the masking tape and a steady hand. For a robot, however, the process would be a simple, freehand one, resulting in neatly painted circuits on every single one of countless robotic minions. Cybernetic domination is at (metallic) hand.

The control surface of the robot, painted with bare conductive paint

One fiddly job for a human, one easy task for robotkind

The instructions and code for Clément’s build can be found here.

Low-tech solutions

Here at Pi Towers, we love seeing the high-tech Raspberry Pi integrated so successfully with low-tech components. In addition to conductive paint, we’ve seen cardboard laptops, toilet roll robots, fruit drum kits, chocolate box robots, and hamster-wheel-triggered cameras. Have you integrated low-tech elements into your projects (and potentially accelerated the robot apocalypse in the process)? Tell us about it in the comments!

 

The post Low-tech Raspberry Pi robot appeared first on Raspberry Pi.

VHostScan – Virtual Host Scanner With Alias & Catch-All Detection

Post Syndicated from Darknet original https://www.darknet.org.uk/2017/10/vhostscan-virtual-host-scanner-with-alias-catch-all-detection/?utm_source=rss&utm_medium=social&utm_campaign=darknetfeed

VHostScan – Virtual Host Scanner With Alias & Catch-All Detection

VHostScan is a Python-based virtual host scanner that can be used with pivot tools, detect catch-all scenarios, aliases and dynamic default pages.

Features of VHostScan Virtual Host Scanner

  • Quickly highlight unique content in catch-all scenarios
  • Locate the outliers in catch-all scenarios where results have dynamic content on the page (such as the time)
  • Identify aliases by tweaking the unique depth of matches
  • Wordlist supports standard words and a variable to input a base hostname (for e.g.

Read the rest of VHostScan – Virtual Host Scanner With Alias & Catch-All Detection now! Only available at Darknet.

JavaScript got better while I wasn’t looking

Post Syndicated from Eevee original https://eev.ee/blog/2017/10/07/javascript-got-better-while-i-wasnt-looking/

IndustrialRobot has generously donated in order to inquire:

In the last few years there seems to have been a lot of activity with adding emojis to Unicode. Has there been an equal effort to add ‘real’ languages/glyph systems/etc?

And as always, if you don’t have anything to say on that topic, feel free to choose your own. :p

Yes.

I mean, each release of Unicode lists major new additions right at the top — Unicode 10, Unicode 9, Unicode 8, etc. They also keep fastidious notes, so you can also dig into how and why these new scripts came from, by reading e.g. the proposal for the addition of Zanabazar Square. I don’t think I have much to add here; I’m not a real linguist, I only play one on TV.

So with that out of the way, here’s something completely different!

A brief history of JavaScript

JavaScript was created in seven days, about eight thousand years ago. It was pretty rough, and it stayed rough for most of its life. But that was fine, because no one used it for anything besides having a trail of sparkles follow your mouse on their Xanga profile.

Then people discovered you could actually do a handful of useful things with JavaScript, and it saw a sharp uptick in usage. Alas, it stayed pretty rough. So we came up with polyfills and jQuerys and all kinds of miscellaneous things that tried to smooth over the rough parts, to varying degrees of success.

And… that’s it. That’s pretty much how things stayed for a while.


I have complicated feelings about JavaScript. I don’t hate it… but I certainly don’t enjoy it, either. It has some pretty neat ideas, like prototypical inheritance and “everything is a value”, but it buries them under a pile of annoying quirks and a woefully inadequate standard library. The DOM APIs don’t make things much better — they seem to be designed as though the target language were Java, rarely taking advantage of any interesting JavaScript features. And the places where the APIs overlap with the language are a hilarious mess: I have to check documentation every single time I use any API that returns a set of things, because there are at least three totally different conventions for handling that and I can’t keep them straight.

The funny thing is that I’ve been fairly happy to work with Lua, even though it shares most of the same obvious quirks as JavaScript. Both languages are weakly typed; both treat nonexistent variables and keys as simply false values, rather than errors; both have a single data structure that doubles as both a list and a map; both use 64-bit floating-point as their only numeric type (though Lua added integers very recently); both lack a standard object model; both have very tiny standard libraries. Hell, Lua doesn’t even have exceptions, not really — you have to fake them in much the same style as Perl.

And yet none of this bothers me nearly as much in Lua. The differences between the languages are very subtle, but combined they make a huge impact.

  • Lua has separate operators for addition and concatenation, so + is never ambiguous. It also has printf-style string formatting in the standard library.

  • Lua’s method calls are syntactic sugar: foo:bar() just means foo.bar(foo). Lua doesn’t even have a special this or self value; the invocant just becomes the first argument. In contrast, JavaScript invokes some hand-waved magic to set its contextual this variable, which has led to no end of confusion.

  • Lua has an iteration protocol, as well as built-in iterators for dealing with list-style or map-style data. JavaScript has a special dedicated Array type and clumsy built-in iteration syntax.

  • Lua has operator overloading and (surprisingly flexible) module importing.

  • Lua allows the keys of a map to be any value (though non-scalars are always compared by identity). JavaScript implicitly converts keys to strings — and since there’s no operator overloading, there’s no way to natively fix this.

These are fairly minor differences, in the grand scheme of language design. And almost every feature in Lua is implemented in a ridiculously simple way; in fact the entire language is described in complete detail in a single web page. So writing JavaScript is always frustrating for me: the language is so close to being much more ergonomic, and yet, it isn’t.

Or, so I thought. As it turns out, while I’ve been off doing other stuff for a few years, browser vendors have been implementing all this pie-in-the-sky stuff from “ES5” and “ES6”, whatever those are. People even upgrade their browsers now. Lo and behold, the last time I went to write JavaScript, I found out that a number of papercuts had actually been solved, and the solutions were sufficiently widely available that I could actually use them in web code.

The weird thing is that I do hear a lot about JavaScript, but the feature I’ve seen raved the most about by far is probably… built-in types for working with arrays of bytes? That’s cool and all, but not exactly the most pressing concern for me.

Anyway, if you also haven’t been keeping tabs on the world of JavaScript, here are some things we missed.

let

MDN docs — supported in Firefox 44, Chrome 41, IE 11, Safari 10

I’m pretty sure I first saw let over a decade ago. Firefox has supported it for ages, but you actually had to opt in by specifying JavaScript version 1.7. Remember JavaScript versions? You know, from back in the days when people actually suggested you write stuff like this:

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<SCRIPT LANGUAGE="JavaScript1.2" TYPE="text/javascript">

Yikes.

Anyway, so, let declares a variable — but scoped to the immediately containing block, unlike var, which scopes to the innermost function. The trouble with var was that it was very easy to make misleading:

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// foo exists here
while (true) {
    var foo = ...;
    ...
}
// foo exists here too

If you reused the same temporary variable name in a different block, or if you expected to be shadowing an outer foo, or if you were trying to do something with creating closures in a loop, this would cause you some trouble.

But no more, because let actually scopes the way it looks like it should, the way variable declarations do in C and friends. As an added bonus, if you refer to a variable declared with let outside of where it’s valid, you’ll get a ReferenceError instead of a silent undefined value. Hooray!

There’s one other interesting quirk to let that I can’t find explicitly documented. Consider:

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let closures = [];
for (let i = 0; i < 4; i++) {
    closures.push(function() { console.log(i); });
}
for (let j = 0; j < closures.length; j++) {
    closures[j]();
}

If this code had used var i, then it would print 4 four times, because the function-scoped var i means each closure is sharing the same i, whose final value is 4. With let, the output is 0 1 2 3, as you might expect, because each run through the loop gets its own i.

But wait, hang on.

The semantics of a C-style for are that the first expression is only evaluated once, at the very beginning. So there’s only one let i. In fact, it makes no sense for each run through the loop to have a distinct i, because the whole idea of the loop is to modify i each time with i++.

I assume this is simply a special case, since it’s what everyone expects. We expect it so much that I can’t find anyone pointing out that the usual explanation for why it works makes no sense. It has the interesting side effect that for no longer de-sugars perfectly to a while, since this will print all 4s:

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closures = [];
let i = 0;
while (i < 4) {
    closures.push(function() { console.log(i); });
    i++;
}
for (let j = 0; j < closures.length; j++) {
    closures[j]();
}

This isn’t a problem — I’m glad let works this way! — it just stands out to me as interesting. Lua doesn’t need a special case here, since it uses an iterator protocol that produces values rather than mutating a visible state variable, so there’s no problem with having the loop variable be truly distinct on each run through the loop.

Classes

MDN docs — supported in Firefox 45, Chrome 42, Safari 9, Edge 13

Prototypical inheritance is pretty cool. The way JavaScript presents it is a little bit opaque, unfortunately, which seems to confuse a lot of people. JavaScript gives you enough functionality to make it work, and even makes it sound like a first-class feature with a property outright called prototype… but to actually use it, you have to do a bunch of weird stuff that doesn’t much look like constructing an object or type.

The funny thing is, people with almost any background get along with Python just fine, and Python uses prototypical inheritance! Nobody ever seems to notice this, because Python tucks it neatly behind a class block that works enough like a Java-style class. (Python also handles inheritance without using the prototype, so it’s a little different… but I digress. Maybe in another post.)

The point is, there’s nothing fundamentally wrong with how JavaScript handles objects; the ergonomics are just terrible.

Lo! They finally added a class keyword. Or, rather, they finally made the class keyword do something; it’s been reserved this entire time.

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class Vector {
    constructor(x, y) {
        this.x = x;
        this.y = y;
    }

    get magnitude() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    }

    dot(other) {
        return this.x * other.x + this.y * other.y;
    }
}

This is all just sugar for existing features: creating a Vector function to act as the constructor, assigning a function to Vector.prototype.dot, and whatever it is you do to make a property. (Oh, there are properties. I’ll get to that in a bit.)

The class block can be used as an expression, with or without a name. It also supports prototypical inheritance with an extends clause and has a super pseudo-value for superclass calls.

It’s a little weird that the inside of the class block has its own special syntax, with function omitted and whatnot, but honestly you’d have a hard time making a class block without special syntax.

One severe omission here is that you can’t declare values inside the block, i.e. you can’t just drop a bar = 3; in there if you want all your objects to share a default attribute. The workaround is to just do this.bar = 3; inside the constructor, but I find that unsatisfying, since it defeats half the point of using prototypes.

Properties

MDN docs — supported in Firefox 4, Chrome 5, IE 9, Safari 5.1

JavaScript historically didn’t have a way to intercept attribute access, which is a travesty. And by “intercept attribute access”, I mean that you couldn’t design a value foo such that evaluating foo.bar runs some code you wrote.

Exciting news: now it does. Or, rather, you can intercept specific attributes, like in the class example above. The above magnitude definition is equivalent to:

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Object.defineProperty(Vector.prototype, 'magnitude', {
    configurable: true,
    enumerable: true,
    get: function() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    },
});

Beautiful.

And what even are these configurable and enumerable things? It seems that every single key on every single object now has its own set of three Boolean twiddles:

  • configurable means the property itself can be reconfigured with another call to Object.defineProperty.
  • enumerable means the property appears in for..in or Object.keys().
  • writable means the property value can be changed, which only applies to properties with real values rather than accessor functions.

The incredibly wild thing is that for properties defined by Object.defineProperty, configurable and enumerable default to false, meaning that by default accessor properties are immutable and invisible. Super weird.

Nice to have, though. And luckily, it turns out the same syntax as in class also works in object literals.

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Vector.prototype = {
    get magnitude() {
        return Math.sqrt(this.x * this.x + this.y * this.y);
    },
    ...
};

Alas, I’m not aware of a way to intercept arbitrary attribute access.

Another feature along the same lines is Object.seal(), which marks all of an object’s properties as non-configurable and prevents any new properties from being added to the object. The object is still mutable, but its “shape” can’t be changed. And of course you can just make the object completely immutable if you want, via setting all its properties non-writable, or just using Object.freeze().

I have mixed feelings about the ability to irrevocably change something about a dynamic runtime. It would certainly solve some gripes of former Haskell-minded colleagues, and I don’t have any compelling argument against it, but it feels like it violates some unwritten contract about dynamic languages — surely any structural change made by user code should also be able to be undone by user code?

Slurpy arguments

MDN docs — supported in Firefox 15, Chrome 47, Edge 12, Safari 10

Officially this feature is called “rest parameters”, but that’s a terrible name, no one cares about “arguments” vs “parameters”, and “slurpy” is a good word. Bless you, Perl.

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function foo(a, b, ...args) {
    // ...
}

Now you can call foo with as many arguments as you want, and every argument after the second will be collected in args as a regular array.

You can also do the reverse with the spread operator:

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let args = [];
args.push(1);
args.push(2);
args.push(3);
foo(...args);

It even works in array literals, even multiple times:

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let args2 = [...args, ...args];
console.log(args2);  // [1, 2, 3, 1, 2, 3]

Apparently there’s also a proposal for allowing the same thing with objects inside object literals.

Default arguments

MDN docs — supported in Firefox 15, Chrome 49, Edge 14, Safari 10

Yes, arguments can have defaults now. It’s more like Sass than Python — default expressions are evaluated once per call, and later default expressions can refer to earlier arguments. I don’t know how I feel about that but whatever.

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function foo(n = 1, m = n + 1, list = []) {
    ...
}

Also, unlike Python, you can have an argument with a default and follow it with an argument without a default, since the default default (!) is and always has been defined as undefined. Er, let me just write it out.

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function bar(a = 5, b) {
    ...
}

Arrow functions

MDN docs — supported in Firefox 22, Chrome 45, Edge 12, Safari 10

Perhaps the most humble improvement is the arrow function. It’s a slightly shorter way to write an anonymous function.

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(a, b, c) => { ... }
a => { ... }
() => { ... }

An arrow function does not set this or some other magical values, so you can safely use an arrow function as a quick closure inside a method without having to rebind this. Hooray!

Otherwise, arrow functions act pretty much like regular functions; you can even use all the features of regular function signatures.

Arrow functions are particularly nice in combination with all the combinator-style array functions that were added a while ago, like Array.forEach.

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[7, 8, 9].forEach(value => {
    console.log(value);
});

Symbol

MDN docs — supported in Firefox 36, Chrome 38, Edge 12, Safari 9

This isn’t quite what I’d call an exciting feature, but it’s necessary for explaining the next one. It’s actually… extremely weird.

symbol is a new kind of primitive (like number and string), not an object (like, er, Number and String). A symbol is created with Symbol('foo'). No, not new Symbol('foo'); that throws a TypeError, for, uh, some reason.

The only point of a symbol is as a unique key. You see, symbols have one very special property: they can be used as object keys, and will not be stringified. Remember, only strings can be keys in JavaScript — even the indices of an array are, semantically speaking, still strings. Symbols are a new exception to this rule.

Also, like other objects, two symbols don’t compare equal to each other: Symbol('foo') != Symbol('foo').

The result is that symbols solve one of the problems that plauges most object systems, something I’ve talked about before: interfaces. Since an interface might be implemented by any arbitrary type, and any arbitrary type might want to implement any number of arbitrary interfaces, all the method names on an interface are effectively part of a single global namespace.

I think I need to take a moment to justify that. If you have IFoo and IBar, both with a method called method, and you want to implement both on the same type… you have a problem. Because most object systems consider “interface” to mean “I have a method called method, with no way to say which interface’s method you mean. This is a hard problem to avoid, because IFoo and IBar might not even come from the same library. Occasionally languages offer a clumsy way to “rename” one method or the other, but the most common approach seems to be for interface designers to avoid names that sound “too common”. You end up with redundant mouthfuls like IFoo.foo_method.

This incredibly sucks, and the only languages I’m aware of that avoid the problem are the ML family and Rust. In Rust, you define all the methods for a particular trait (interface) in a separate block, away from the type’s “own” methods. It’s pretty slick. You can still do obj.method(), and as long as there’s only one method among all the available traits, you’ll get that one. If not, there’s syntax for explicitly saying which trait you mean, which I can’t remember because I’ve never had to use it.

Symbols are JavaScript’s answer to this problem. If you want to define some interface, you can name its methods with symbols, which are guaranteed to be unique. You just have to make sure you keep the symbol around somewhere accessible so other people can actually use it. (Or… not?)

The interesting thing is that JavaScript now has several of its own symbols built in, allowing user objects to implement features that were previously reserved for built-in types. For example, you can use the Symbol.hasInstance symbol — which is simply where the language is storing an existing symbol and is not the same as Symbol('hasInstance')! — to override instanceof:

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// oh my god don't do this though
class EvenNumber {
    static [Symbol.hasInstance](obj) {
        return obj % 2 == 0;
    }
}
console.log(2 instanceof EvenNumber);  // true
console.log(3 instanceof EvenNumber);  // false

Oh, and those brackets around Symbol.hasInstance are a sort of reverse-quoting — they indicate an expression to use where the language would normally expect a literal identifier. I think they work as object keys, too, and maybe some other places.

The equivalent in Python is to implement a method called __instancecheck__, a name which is not special in any way except that Python has reserved all method names of the form __foo__. That’s great for Python, but doesn’t really help user code. JavaScript has actually outclassed (ho ho) Python here.

Of course, obj[BobNamespace.some_method]() is not the prettiest way to call an interface method, so it’s not perfect. I imagine this would be best implemented in user code by exposing a polymorphic function, similar to how Python’s len(obj) pretty much just calls obj.__len__().

I only bring this up because it’s the plumbing behind one of the most incredible things in JavaScript that I didn’t even know about until I started writing this post. I’m so excited oh my gosh. Are you ready? It’s:

Iteration protocol

MDN docs — supported in Firefox 27, Chrome 39, Safari 10; still experimental in Edge

Yes! Amazing! JavaScript has first-class support for iteration! I can’t even believe this.

It works pretty much how you’d expect, or at least, how I’d expect. You give your object a method called Symbol.iterator, and that returns an iterator.

What’s an iterator? It’s an object with a next() method that returns the next value and whether the iterator is exhausted.

Wait, wait, wait a second. Hang on. The method is called next? Really? You didn’t go for Symbol.next? Python 2 did exactly the same thing, then realized its mistake and changed it to __next__ in Python 3. Why did you do this?

Well, anyway. My go-to test of an iterator protocol is how hard it is to write an equivalent to Python’s enumerate(), which takes a list and iterates over its values and their indices. In Python it looks like this:

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for i, value in enumerate(['one', 'two', 'three']):
    print(i, value)
# 0 one
# 1 two
# 2 three

It’s super nice to have, and I’m always amazed when languages with “strong” “support” for iteration don’t have it. Like, C# doesn’t. So if you want to iterate over a list but also need indices, you need to fall back to a C-style for loop. And if you want to iterate over a lazy or arbitrary iterable but also need indices, you need to track it yourself with a counter. Ridiculous.

Here’s my attempt at building it in JavaScript.

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function enumerate(iterable) {
    // Return a new iter*able* object with a Symbol.iterator method that
    // returns an iterator.
    return {
        [Symbol.iterator]: function() {
            let iterator = iterable[Symbol.iterator]();
            let i = 0;

            return {
                next: function() {
                    let nextval = iterator.next();
                    if (! nextval.done) {
                        nextval.value = [i, nextval.value];
                        i++;
                    }
                    return nextval;
                },
            };
        },
    };
}
for (let [i, value] of enumerate(['one', 'two', 'three'])) {
    console.log(i, value);
}
// 0 one
// 1 two
// 2 three

Incidentally, for..of (which iterates over a sequence, unlike for..in which iterates over keys — obviously) is finally supported in Edge 12. Hallelujah.

Oh, and let [i, value] is destructuring assignment, which is also a thing now and works with objects as well. You can even use the splat operator with it! Like Python! (And you can use it in function signatures! Like Python! Wait, no, Python decided that was terrible and removed it in 3…)

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let [x, y, ...others] = ['apple', 'orange', 'cherry', 'banana'];

It’s a Halloween miracle. 🎃

Generators

MDN docs — supported in Firefox 26, Chrome 39, Edge 13, Safari 10

That’s right, JavaScript has goddamn generators now. It’s basically just copying Python and adding a lot of superfluous punctuation everywhere. Not that I’m complaining.

Also, generators are themselves iterable, so I’m going to cut to the chase and rewrite my enumerate() with a generator.

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function enumerate(iterable) {
    return {
        [Symbol.iterator]: function*() {
            let i = 0;
            for (let value of iterable) {
                yield [i, value];
                i++;
            }
        },
    };
}
for (let [i, value] of enumerate(['one', 'two', 'three'])) {
    console.log(i, value);
}
// 0 one
// 1 two
// 2 three

Amazing. function* is a pretty strange choice of syntax, but whatever? I guess it also lets them make yield only act as a keyword inside a generator, for ultimate backwards compatibility.

JavaScript generators support everything Python generators do: yield* yields every item from a subsequence, like Python’s yield from; generators can return final values; you can pass values back into the generator if you iterate it by hand. No, really, I wasn’t kidding, it’s basically just copying Python. It’s great. You could now built asyncio in JavaScript!

In fact, they did that! JavaScript now has async and await. An async function returns a Promise, which is also a built-in type now. Amazing.

Sets and maps

MDN docs for MapMDN docs for Set — supported in Firefox 13, Chrome 38, IE 11, Safari 7.1

I did not save the best for last. This is much less exciting than generators. But still exciting.

The only data structure in JavaScript is the object, a map where the strings are keys. (Or now, also symbols, I guess.) That means you can’t readily use custom values as keys, nor simulate a set of arbitrary objects. And you have to worry about people mucking with Object.prototype, yikes.

But now, there’s Map and Set! Wow.

Unfortunately, because JavaScript, Map couldn’t use the indexing operators without losing the ability to have methods, so you have to use a boring old method-based API. But Map has convenient methods that plain objects don’t, like entries() to iterate over pairs of keys and values. In fact, you can use a map with for..of to get key/value pairs. So that’s nice.

Perhaps more interesting, there’s also now a WeakMap and WeakSet, where the keys are weak references. I don’t think JavaScript had any way to do weak references before this, so that’s pretty slick. There’s no obvious way to hold a weak value, but I guess you could substitute a WeakSet with only one item.

Template literals

MDN docs — supported in Firefox 34, Chrome 41, Edge 12, Safari 9

Template literals are JavaScript’s answer to string interpolation, which has historically been a huge pain in the ass because it doesn’t even have string formatting in the standard library.

They’re just strings delimited by backticks instead of quotes. They can span multiple lines and contain expressions.

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console.log(`one plus
two is ${1 + 2}`);

Someone decided it would be a good idea to allow nesting more sets of backticks inside a ${} expression, so, good luck to syntax highlighters.

However, someone also had the most incredible idea ever, which was to add syntax allowing user code to do the interpolation — so you can do custom escaping, when absolutely necessary, which is virtually never, because “escaping” means you’re building a structured format by slopping strings together willy-nilly instead of using some API that works with the structure.

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// OF COURSE, YOU SHOULDN'T BE DOING THIS ANYWAY; YOU SHOULD BUILD HTML WITH
// THE DOM API AND USE .textContent FOR LITERAL TEXT.  BUT AS AN EXAMPLE:
function html(literals, ...values) {
    let ret = [];
    literals.forEach((literal, i) => {
        if (i > 0) {
            // Is there seriously still not a built-in function for doing this?
            // Well, probably because you SHOULDN'T BE DOING IT
            ret.push(values[i - 1]
                .replace(/&/g, '&amp;')
                .replace(/</g, '&lt;')
                .replace(/>/g, '&gt;')
                .replace(/"/g, '&quot;')
                .replace(/'/g, '&apos;'));
        }
        ret.push(literal);
    });
    return ret.join('');
}
let username = 'Bob<script>';
let result = html`<b>Hello, ${username}!</b>`;
console.log(result);
// <b>Hello, Bob&lt;script&gt;!</b>

It’s a shame this feature is in JavaScript, the language where you are least likely to need it.

Trailing commas

Remember how you couldn’t do this for ages, because ass-old IE considered it a syntax error and would reject the entire script?

1
2
3
4
5
{
    a: 'one',
    b: 'two',
    c: 'three',  // <- THIS GUY RIGHT HERE
}

Well now it’s part of the goddamn spec and if there’s anything in this post you can rely on, it’s this. In fact you can use AS MANY GODDAMN TRAILING COMMAS AS YOU WANT. But only in arrays.

1
[1, 2, 3,,,,,,,,,,,,,,,,,,,,,,,,,]

Apparently that has the bizarre side effect of reserving extra space at the end of the array, without putting values there.

And more, probably

Like strict mode, which makes a few silent “errors” be actual errors, forces you to declare variables (no implicit globals!), and forbids the completely bozotic with block.

Or String.trim(), which trims whitespace off of strings.

Or… Math.sign()? That’s new? Seriously? Well, okay.

Or the Proxy type, which lets you customize indexing and assignment and calling. Oh. I guess that is possible, though this is a pretty weird way to do it; why not just use symbol-named methods?

You can write Unicode escapes for astral plane characters in strings (or identifiers!), as \u{XXXXXXXX}.

There’s a const now? I extremely don’t care, just name it in all caps and don’t reassign it, come on.

There’s also a mountain of other minor things, which you can peruse at your leisure via MDN or the ECMAScript compatibility tables (note the links at the top, too).

That’s all I’ve got. I still wouldn’t say I’m a big fan of JavaScript, but it’s definitely making an effort to clean up some goofy inconsistencies and solve common problems. I think I could even write some without yelling on Twitter about it now.

On the other hand, if you’re still stuck supporting IE 10 for some reason… well, er, my condolences.

RaspiReader: build your own fingerprint reader

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/raspireader-fingerprint-scanner/

Three researchers from Michigan State University have developed a low-cost, open-source fingerprint reader which can detect fake prints. They call it RaspiReader, and they’ve built it using a Raspberry Pi 3 and two Camera Modules. Joshua and his colleagues have just uploaded all the info you need to build your own version — let’s go!

GIF of fingerprint match points being aligned on fingerprint, not real output of RaspiReader software

Sadly not the real output of the RaspiReader

Falsified fingerprints

We’ve probably all seen a movie in which a burglar crosses a room full of laser tripwires and then enters the safe full of loot by tricking the fingerprint-secured lock with a fake print. Turns out, the second part is not that unrealistic: you can fake fingerprints using a range of materials, such as glue or latex.

Examples of live and fake fingerprints collected by the RaspiReader team

The RaspiReader team collected live and fake fingerprints to test the device

If the spoof print layer capping the spoofer’s finger is thin enough, it can even fool readers that detect blood flow, pulse, or temperature. This is becoming a significant security risk, not least for anyone who unlocks their smartphone using a fingerprint.

The RaspiReader

This is where Anil K. Jain comes in: Professor Jain leads a biometrics research group. Under his guidance, Joshua J. Engelsma and Kai Cao set out to develop a fingerprint reader with improved spoof-print detection. Ultimately, they aim to help the development of more secure commercial technologies. With their project, the team has also created an amazing resource for anyone who wants to build their own fingerprint reader.

So that replicating their device would be easy, they wanted to make it using inexpensive, readily available components, which is why they turned to Raspberry Pi technology.

RaspiReader fingerprint scanner by PRIP lab

The Raspireader and its output

Inside the RaspiReader’s 3D-printed housing, LEDs shine light through an acrylic prism, on top of which the user rests their finger. The prism refracts the light so that the two Camera Modules can take images from different angles. The Pi receives these images via a Multi Camera Adapter Module feeding into the CSI port. Collecting two images means the researchers’ spoof detection algorithm has more information to work with.

Comparison of live and spoof fingerprints

Real on the left, fake on the right

RaspiReader software

The Camera Adaptor uses the RPi.GPIO Python package. The RaspiReader performs image processing, and its spoof detection takes image colour and 3D friction ridge patterns into account. The detection algorithm extracts colour local binary patterns … please don’t ask me to explain! You can have a look at the researchers’ manuscript if you want to get stuck into the fine details of their project.

Build your own fingerprint reader

I’ve had my eyes glued to my inbox waiting for Josh to send me links to instructions and files for this build, and here they are (thanks, Josh)! Check out the video tutorial, which walks you through how to assemble the RaspiReader:

RaspiReader: Cost-Effective Open-Source Fingerprint Reader

Building a cost-effective, open-source, and spoof-resilient fingerprint reader for $160* in under an hour. Code: https://github.com/engelsjo/RaspiReader Links to parts: 1. PRISM – https://www.amazon.com/gp/product/B00WL3OBK4/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1 (Better fit) https://www.thorlabs.com/thorproduct.cfm?partnumber=PS611 2. RaspiCams – https://www.amazon.com/gp/product/B012V1HEP4/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 3. Camera Multiplexer https://www.amazon.com/gp/product/B012UQWOOQ/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1 4. Raspberry Pi Kit: https://www.amazon.com/CanaKit-Raspberry-Clear-Power-Supply/dp/B01C6EQNNK/ref=sr_1_6?ie=UTF8&qid=1507058509&sr=8-6&keywords=raspberry+pi+3b Whitepaper: https://arxiv.org/abs/1708.07887 * Prices can vary based on Amazon’s pricing. P.s.

You can find a parts list with links to suppliers in the video description — the whole build costs around $160. All the STL files for the housing and the Python scripts you need to run on the Pi are available on Josh’s GitHub.

Enhance your home security

The RaspiReader is a great resource for researchers, and it would also be a terrific project to build at home! Is there a more impressive way to protect a treasured possession, or secure access to your computer, than with a DIY fingerprint scanner?

Check out this James-Bond-themed blog post for Raspberry Pi resources to help you build a high-security lair. If you want even more inspiration, watch this video about a laser-secured cookie jar which Estefannie made for us. And be sure to share your successful fingerprint scanner builds with us via social media!

The post RaspiReader: build your own fingerprint reader appeared first on Raspberry Pi.

Now Available – Amazon Linux AMI 2017.09

Post Syndicated from Jeff Barr original https://aws.amazon.com/blogs/aws/now-available-amazon-linux-ami-2017-09/

I’m happy to announce that the latest version of the Amazon Linux AMI (2017.09) is now available in all AWS Regions for all current-generation EC2 instances. The AMI contains a supported and maintained Linux image that is designed to provide a stable, secure, high performance environment for applications running on EC2.

Easy Upgrade
You can upgrade your existing instances by running two commands and then rebooting:

$ sudo yum clean all
$ sudo yum update

Lots of Goodies
The AMI contains many new features, many of which were added in response to requests from our customers. Here’s a summary:

Kernel 4.9.51 – Based on the 4.9 stable kernel series, this kernel includes the ENA 1.3.0 driver along with support for TCP Bottleneck Bandwidth and RTT (BBR). Read my post, Elastic Network Adapter – High-Performance Network Interface for Amazon EC2 to learn more about ENA. Read the Release Notes to learn how to enable BBR.

Amazon SSM Agent – The Amazon SSM Agent is now installed by default. This means that you can now use EC2 Run Command to configure and run scripts on your instances with no further setup. To learn more, read Executing Commands Using Systems Manager Run Command or Manage Instances at Scale Without SSH Access Using EC2 Run Command.

Python 3.6 – The newest version of Python is now included and can be managed via virtualenv and alternatives. You can install Python 3.6 like this:

$ sudo yum install python36 python36-virtualenv python36-pip

Ruby 2.4 – The latest version of Ruby in the 2.4 series is now available. Install it like this:

$ sudo yum install ruby24

OpenSSL – The AMI now uses OpenSSL 1.0.2k.

HTTP/2 – The HTTP/2 protocol is now supported by the AMI’s httpd24, nginx, and curl packages.

Relational DatabasesPostgres 9.6 and MySQL 5.7 are now available, and can be installed like this:

$ sudo yum install postgresql96
$ sudo yum install mysql57

OpenMPI – The OpenMPI package has been upgraded from 1.6.4 to 2.1.1. OpenMPI compatibility packages are available and can be used to build and run older OpenMPI applications.

And More – Other updated packages include Squid 3.5, Nginx 1.12, Tomcat 8.5, and GCC 6.4.

Launch it Today
You can use this AMI to launch EC2 instances in all AWS Regions today. It is available for EBS-backed and Instance Store-backed instances and supports HVM and PV modes.

Jeff;

PlayerUnknown’s Battlegrounds on a Game Boy?!

Post Syndicated from Alex Bate original https://www.raspberrypi.org/blog/playerunknowns-battlegrounds-game-boy/

My evenings spent watching the Polygon Awful Squad play PlayerUnknown’s Battlegrounds for hours on end have made me mildly obsessed with this record-breaking Steam game.

PlayerUnknown's Battlegrounds Raspberry Pi

So when Michael Darby’s latest PUBG-inspired Game Boy build appeared in my notifications last week, I squealed with excitement and quickly sent the link to my team…while drinking a cocktail by a pool in Turkey ☀️🍹

PUBG ON A GAMEBOY

https://314reactor.com/ https://www.hackster.io/314reactor https://twitter.com/the_mikey_d

PlayerUnknown’s Battlegrounds

For those unfamiliar with the game: PlayerUnknown’s Battlegrounds, or PUBG for short, is a Battle-Royale-style multiplayer online video game in which individuals or teams fight to the death on an island map. As players collect weapons, ammo, and transport, their ‘safe zone’ shrinks, forcing a final face-off until only one character remains.

The game has been an astounding success on Steam, the digital distribution platform which brings PUBG to the masses. It records daily player counts of over a million!

PlayerUnknown's Battlegrounds Raspberry Pi

Yeah, I’d say one or two people seem to enjoy it!

PUBG on a Game Boy?!

As it’s a fairly complex game, let’s get this out of the way right now: no, Michael is not running the entire game on a Nintendo Game Boy. That would be magic silly impossible. Instead, he’s streaming the game from his home PC to a Raspberry Pi Zero W fitted within the hacked handheld console.

Michael removed the excess plastic inside an old Game Boy Color shell to make space for a Zero W, LiPo battery, and TFT screen. He then soldered the necessary buttons to GPIO pins, and wrote a Python script to control them.

PlayerUnknown's Battlegrounds Raspberry Pi

The maker battleground

The full script can be found here, along with a more detailed tutorial for the build.

In order to stream PUBG to the Zero W, Michael uses the open-source NVIDIA steaming service Moonlight. He set his PC’s screen resolution to 800×600 and its frame rate to 30, so that streaming the game to the TFT screen works perfectly, albeit with no sound.

PlayerUnknown's Battlegrounds Raspberry Pi

The end result is a rather impressive build that has confused YouTube commenters since he uploaded footage for it last week. The video has more than 60000 views to date, so it appears we’re not the only ones impressed with Michael’s make.

314reactor

If you’re a regular reader of our blog, you may recognise Michael’s name from his recent Nerf blaster mod. And fans of Raspberry Pi may also have seen his Pi-powered Windows 98 wristwatch earlier in the year. He blogs at 314reactor, where you can read more about his digital making projects.

Windows 98 Wrist watch Raspberry Pi PlayerUnknown's Battlegrounds

Player Two has entered the game

Now it’s your turn. Have you used a Raspberry Pi to create a gaming system? I’m not just talking arcades and RetroPie here. We want to see everything, from Pi-powered board games to tech on the football field.

Share your builds in the comments below and while you’re at it, what game would you like to stream to a handheld device?

The post PlayerUnknown’s Battlegrounds on a Game Boy?! appeared first on Raspberry Pi.

Algo-rhythmic PianoAI

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/pianoai/

It’s no secret that we love music projects at Pi Towers. On the contrary, we often shout it from the rooftops like we’re in Moulin Rouge! But the PianoAI project by Zack left us slack-jawed: he built an AI on a Raspberry Pi that listens to his piano playing, and then produces improvised, real-time accompaniment.

Jamming with PIanoAI (clip #1) (Version 1.0)

Another example of a short teaching and then jamming with piano with a version I’m more happy with. I have to play for the Pi for a little while before the Pi has enough data to make its own music.

The PianoAI

Inspired by a story about jazz musician Dan Tepfer, Zack set out to create an AI able to imitate his piano-playing style in real time. He began programming the AI in Python, before starting over in the open-source programming language Go.

The Go language gopher mascot with headphones and a MIDI keyboard

The Go mascot is a gopher. Why not?

Zack has published an excellent write-up of how he built PianoAI. It’s a very readable account of the progress he made and the obstacles he had to overcome while writing PianoAI, and it includes more example videos. It’s hard to add anything to Zack’s own words, so I shan’t try.

Paper notes for PianoAI algorithm

Some of Zack’s notes for his AI

If you just want to try out PianoAI, head over to his GitHub. He provides a detailed guide that talks you through how to implement and use it.

Music to our ears

The Raspberry Pi community never fails to amaze us with their wonderful builds, not least when it comes to musical ones. Check out this cool-looking synth by Toby Hendricks, this geometric instrument by David Sharples, and this pyrite-disc-reading music player by Dmitry Morozov. Aren’t they all splendid? And the list goes on and on

Which instrument do you play? The recorder? The ocarina? The jaw harp? Could you create an AI like Zack’s for it? Let us know in the comments below, and share your builds with us via social media.

The post Algo-rhythmic PianoAI appeared first on Raspberry Pi.

Creating a Cost-Efficient Amazon ECS Cluster for Scheduled Tasks

Post Syndicated from Nathan Taber original https://aws.amazon.com/blogs/compute/creating-a-cost-efficient-amazon-ecs-cluster-for-scheduled-tasks/

Madhuri Peri
Sr. DevOps Consultant

When you use Amazon Relational Database Service (Amazon RDS), depending on the logging levels on the RDS instances and the volume of transactions, you could generate a lot of log data. To ensure that everything is running smoothly, many customers search for log error patterns using different log aggregation and visualization systems, such as Amazon Elasticsearch Service, Splunk, or other tool of their choice. A module needs to periodically retrieve the RDS logs using the SDK, and then send them to Amazon S3. From there, you can stream them to your log aggregation tool.

One option is writing an AWS Lambda function to retrieve the log files. However, because of the time that this function needs to execute, depending on the volume of log files retrieved and transferred, it is possible that Lambda could time out on many instances.  Another approach is launching an Amazon EC2 instance that runs this job periodically. However, this would require you to run an EC2 instance continuously, not an optimal use of time or money.

Using the new Amazon CloudWatch integration with Amazon EC2 Container Service, you can trigger this job to run in a container on an existing Amazon ECS cluster. Additionally, this would allow you to improve costs by running containers on a fleet of Spot Instances.

In this post, I will show you how to use the new scheduled tasks (cron) feature in Amazon ECS and launch tasks using CloudWatch events, while leveraging Spot Fleet to maximize availability and cost optimization for containerized workloads.

Architecture

The following diagram shows how the various components described schedule a task that retrieves log files from Amazon RDS database instances, and deposits the logs into an S3 bucket.

Amazon ECS cluster container instances are using Spot Fleet, which is a perfect match for the workload that needs to run when it can. This improves cluster costs.

The task definition defines which Docker image to retrieve from the Amazon EC2 Container Registry (Amazon ECR) repository and run on the Amazon ECS cluster.

The container image has Python code functions to make AWS API calls using boto3. It iterates over the RDS database instances, retrieves the logs, and deposits them in the S3 bucket. Many customers choose these logs to be delivered to their centralized log-store. CloudWatch Events defines the schedule for when the container task has to be launched.

Walkthrough

To provide the basic framework, we have built an AWS CloudFormation template that creates the following resources:

  • Amazon ECR repository for storing the Docker image to be used in the task definition
  • S3 bucket that holds the transferred logs
  • Task definition, with image name and S3 bucket as environment variables provided via input parameter
  • CloudWatch Events rule
  • Amazon ECS cluster
  • Amazon ECS container instances using Spot Fleet
  • IAM roles required for the container instance profiles

Before you begin

Ensure that Git, Docker, and the AWS CLI are installed on your computer.

In your AWS account, instantiate one Amazon Aurora instance using the console. For more information, see Creating an Amazon Aurora DB Cluster.

Implementation Steps

  1. Clone the code from GitHub that performs RDS API calls to retrieve the log files.
    git clone https://github.com/awslabs/aws-ecs-scheduled-tasks.git
  2. Build and tag the image.
    cd aws-ecs-scheduled-tasks/container-code/src && ls

    Dockerfile		rdslogsshipper.py	requirements.txt

    docker build -t rdslogsshipper .

    Sending build context to Docker daemon 9.728 kB
    Step 1 : FROM python:3
     ---> 41397f4f2887
    Step 2 : WORKDIR /usr/src/app
     ---> Using cache
     ---> 59299c020e7e
    Step 3 : COPY requirements.txt ./
     ---> 8c017e931c3b
    Removing intermediate container df09e1bed9f2
    Step 4 : COPY rdslogsshipper.py /usr/src/app
     ---> 099a49ca4325
    Removing intermediate container 1b1da24a6699
    Step 5 : RUN pip install --no-cache-dir -r requirements.txt
     ---> Running in 3ed98b30901d
    Collecting boto3 (from -r requirements.txt (line 1))
      Downloading boto3-1.4.6-py2.py3-none-any.whl (128kB)
    Collecting botocore (from -r requirements.txt (line 2))
      Downloading botocore-1.6.7-py2.py3-none-any.whl (3.6MB)
    Collecting s3transfer<0.2.0,>=0.1.10 (from boto3->-r requirements.txt (line 1))
      Downloading s3transfer-0.1.10-py2.py3-none-any.whl (54kB)
    Collecting jmespath<1.0.0,>=0.7.1 (from boto3->-r requirements.txt (line 1))
      Downloading jmespath-0.9.3-py2.py3-none-any.whl
    Collecting python-dateutil<3.0.0,>=2.1 (from botocore->-r requirements.txt (line 2))
      Downloading python_dateutil-2.6.1-py2.py3-none-any.whl (194kB)
    Collecting docutils>=0.10 (from botocore->-r requirements.txt (line 2))
      Downloading docutils-0.14-py3-none-any.whl (543kB)
    Collecting six>=1.5 (from python-dateutil<3.0.0,>=2.1->botocore->-r requirements.txt (line 2))
      Downloading six-1.10.0-py2.py3-none-any.whl
    Installing collected packages: six, python-dateutil, docutils, jmespath, botocore, s3transfer, boto3
    Successfully installed boto3-1.4.6 botocore-1.6.7 docutils-0.14 jmespath-0.9.3 python-dateutil-2.6.1 s3transfer-0.1.10 six-1.10.0
     ---> f892d3cb7383
    Removing intermediate container 3ed98b30901d
    Step 6 : COPY . .
     ---> ea7550c04fea
    Removing intermediate container b558b3ebd406
    Successfully built ea7550c04fea
  3. Run the CloudFormation stack and get the names for the Amazon ECR repo and S3 bucket. In the stack, choose Outputs.
  4. Open the ECS console and choose Repositories. The rdslogs repo has been created. Choose View Push Commands and follow the instructions to connect to the repository and push the image for the code that you built in Step 2. The screenshot shows the final result:
  5. Associate the CloudWatch scheduled task with the created Amazon ECS Task Definition, using a new CloudWatch event rule that is scheduled to run at intervals. The following rule is scheduled to run every 15 minutes:
    aws --profile default --region us-west-2 events put-rule --name demo-ecs-task-rule  --schedule-expression "rate(15 minutes)"

    {
        "RuleArn": "arn:aws:events:us-west-2:12345678901:rule/demo-ecs-task-rule"
    }
  6. CloudWatch requires IAM permissions to place a task on the Amazon ECS cluster when the CloudWatch event rule is executed, in addition to an IAM role that can be assumed by CloudWatch Events. This is done in three steps:
    1. Create the IAM role to be assumed by CloudWatch.
      aws --profile default --region us-west-2 iam create-role --role-name Test-Role --assume-role-policy-document file://event-role.json

      {
          "Role": {
              "AssumeRolePolicyDocument": {
                  "Version": "2012-10-17", 
                  "Statement": [
                      {
                          "Action": "sts:AssumeRole", 
                          "Effect": "Allow", 
                          "Principal": {
                              "Service": "events.amazonaws.com"
                          }
                      }
                  ]
              }, 
              "RoleId": "AROAIRYYLDCVZCUACT7FS", 
              "CreateDate": "2017-07-14T22:44:52.627Z", 
              "RoleName": "Test-Role", 
              "Path": "/", 
              "Arn": "arn:aws:iam::12345678901:role/Test-Role"
          }
      }

      The following is an example of the event-role.json file used earlier:

      {
          "Version": "2012-10-17",
          "Statement": [
              {
                  "Effect": "Allow",
                  "Principal": {
                    "Service": "events.amazonaws.com"
                  },
                  "Action": "sts:AssumeRole"
              }
          ]
      }
    2. Create the IAM policy defining the ECS cluster and task definition. You need to get these values from the CloudFormation outputs and resources.
      aws --profile default --region us-west-2 iam create-policy --policy-name test-policy --policy-document file://event-policy.json

      {
          "Policy": {
              "PolicyName": "test-policy", 
              "CreateDate": "2017-07-14T22:51:20.293Z", 
              "AttachmentCount": 0, 
              "IsAttachable": true, 
              "PolicyId": "ANPAI7XDIQOLTBUMDWGJW", 
              "DefaultVersionId": "v1", 
              "Path": "/", 
              "Arn": "arn:aws:iam::123455678901:policy/test-policy", 
              "UpdateDate": "2017-07-14T22:51:20.293Z"
          }
      }

      The following is an example of the event-policy.json file used earlier:

      {
          "Version": "2012-10-17",
          "Statement": [
            {
                "Effect": "Allow",
                "Action": [
                    "ecs:RunTask"
                ],
                "Resource": [
                    "arn:aws:ecs:*::task-definition/"
                ],
                "Condition": {
                    "ArnLike": {
                        "ecs:cluster": "arn:aws:ecs:*::cluster/"
                    }
                }
            }
          ]
      }
    3. Attach the IAM policy to the role.
      aws --profile default --region us-west-2 iam attach-role-policy --role-name Test-Role --policy-arn arn:aws:iam::1234567890:policy/test-policy
  7. Associate the CloudWatch rule created earlier to place the task on the ECS cluster. The following command shows an example. Replace the AWS account ID and region with your settings.
    aws events put-targets --rule demo-ecs-task-rule --targets "Id"="1","Arn"="arn:aws:ecs:us-west-2:12345678901:cluster/test-cwe-blog-ecsCluster-15HJFWCH4SP67","EcsParameters"={"TaskDefinitionArn"="arn:aws:ecs:us-west-2:12345678901:task-definition/test-cwe-blog-taskdef:8"},"RoleArn"="arn:aws:iam::12345678901:role/Test-Role"

    {
        "FailedEntries": [], 
        "FailedEntryCount": 0
    }

That’s it. The logs now run based on the defined schedule.

To test this, open the Amazon ECS console, select the Amazon ECS cluster that you created, and then choose Tasks, Run New Task. Select the task definition created by the CloudFormation template, and the cluster should be selected automatically. As this runs, the S3 bucket should be populated with the RDS logs for the instance.

Conclusion

In this post, you’ve seen that the choices for workloads that need to run at a scheduled time include Lambda with CloudWatch events or EC2 with cron. However, sometimes the job could run outside of Lambda execution time limits or be not cost-effective for an EC2 instance.

In such cases, you can schedule the tasks on an ECS cluster using CloudWatch rules. In addition, you can use a Spot Fleet cluster with Amazon ECS for cost-conscious workloads that do not have hard requirements on execution time or instance availability in the Spot Fleet. For more information, see Powering your Amazon ECS Cluster with Amazon EC2 Spot Instances and Scheduled Events.

If you have questions or suggestions, please comment below.

Using Enhanced Request Authorizers in Amazon API Gateway

Post Syndicated from Stefano Buliani original https://aws.amazon.com/blogs/compute/using-enhanced-request-authorizers-in-amazon-api-gateway/

Recently, AWS introduced a new type of authorizer in Amazon API Gateway, enhanced request authorizers. Previously, custom authorizers received only the bearer token included in the request and the ARN of the API Gateway method being called. Enhanced request authorizers receive all of the headers, query string, and path parameters as well as the request context. This enables you to make more sophisticated authorization decisions based on parameters such as the client IP address, user agent, or a query string parameter alongside the client bearer token.

Enhanced request authorizer configuration

From the API Gateway console, you can declare a new enhanced request authorizer by selecting the Request option as the AWS Lambda event payload:

Create enhanced request authorizer

 

Just like normal custom authorizers, API Gateway can cache the policy returned by your Lambda function. With enhanced request authorizers, however, you can also specify the values that form the unique key of a policy in the cache. For example, if your authorization decision is based on both the bearer token and the IP address of the client, both values should be part of the unique key in the policy cache. The identity source parameter lets you specify these values as mapping expressions:

  • The bearer token appears in the Authorization header
  • The client IP address is stored in the sourceIp parameter of the request context.

Configure identity sources

 

Using enhanced request authorizers with Swagger

You can also define enhanced request authorizers in your Swagger (Open API) definitions. In the following example, you can see that all of the options configured in the API Gateway console are available as custom extensions in the API definition. For example, the identitySource field is a comma-separated list of mapping expressions.

securityDefinitions:
  IpAuthorizer:
    type: "apiKey"
    name: "IpAuthorizer"
    in: "header"
    x-amazon-apigateway-authtype: "custom"
    x-amazon-apigateway-authorizer:
      authorizerResultTtlInSeconds: 300
      identitySource: "method.request.header.Authorization, context.identity.sourceIp"
      authorizerUri: "arn:aws:apigateway:us-east-1:lambda:path/2015-03-31/functions/arn:aws:lambda:us-east-1:XXXXXXXXXX:function:py-ip-authorizer/invocations"
      type: "request"

After you have declared your authorizer in the security definitions section, you can use it in your API methods:

---
swagger: "2.0"
info:
  title: "request-authorizer-demo"
basePath: "/dev"
paths:
  /hello:
    get:
      security:
      - IpAuthorizer: []
...

Enhanced request authorizer Lambda functions

Enhanced request authorizer Lambda functions receive an event object that is similar to proxy integrations. It contains all of the information about a request, excluding the body.

{
    "methodArn": "arn:aws:execute-api:us-east-1:XXXXXXXXXX:xxxxxx/dev/GET/hello",
    "resource": "/hello",
    "requestContext": {
        "resourceId": "xxxx",
        "apiId": "xxxxxxxxx",
        "resourcePath": "/hello",
        "httpMethod": "GET",
        "requestId": "9e04ff18-98a6-11e7-9311-ef19ba18fc8a",
        "path": "/dev/hello",
        "accountId": "XXXXXXXXXXX",
        "identity": {
            "apiKey": "",
            "sourceIp": "58.240.196.186"
        },
        "stage": "dev"
    },
    "queryStringParameters": {},
    "httpMethod": "GET",
    "pathParameters": {},
    "headers": {
        "cache-control": "no-cache",
        "x-amzn-ssl-client-hello": "AQACJAMDAAAAAAAAAAAAAAAAAAAAAAAAAAAA…",
        "Accept-Encoding": "gzip, deflate",
        "X-Forwarded-For": "54.240.196.186, 54.182.214.90",
        "Accept": "*/*",
        "User-Agent": "PostmanRuntime/6.2.5",
        "Authorization": "hello"
    },
    "stageVariables": {},
    "path": "/hello",
    "type": "REQUEST"
}

The following enhanced request authorizer snippet is written in Python and compares the source IP address against a list of valid IP addresses. The comments in the code explain what happens in each step.

...
VALID_IPS = ["58.240.195.186", "201.246.162.38"]

def lambda_handler(event, context):

    # Read the client’s bearer token.
    jwtToken = event["headers"]["Authorization"]
    
    # Read the source IP address for the request form 
    # for the API Gateway context object.
    clientIp = event["requestContext"]["identity"]["sourceIp"]
    
    # Verify that the client IP address is allowed.
    # If it’s not valid, raise an exception to make sure
    # that API Gateway returns a 401 status code.
    if clientIp not in VALID_IPS:
        raise Exception('Unauthorized')
    
    # Only allow hello users in!
    if not validate_jwt(userId):
        raise Exception('Unauthorized')

    # Use the values from the event object to populate the 
    # required parameters in the policy object.
    policy = AuthPolicy(userId, event["requestContext"]["accountId"])
    policy.restApiId = event["requestContext"]["apiId"]
    policy.region = event["methodArn"].split(":")[3]
    policy.stage = event["requestContext"]["stage"]
    
    # Use the scopes from the bearer token to make a 
    # decision on which methods to allow in the API.
    policy.allowMethod(HttpVerb.GET, '/hello')

    # Finally, build the policy.
    authResponse = policy.build()

    return authResponse
...

Conclusion

API Gateway customers build complex APIs, and authorization decisions often go beyond the simple properties in a JWT token. For example, users may be allowed to call the “list cars” endpoint but only with a specific subset of filter parameters. With enhanced request authorizers, you have access to all request parameters. You can centralize all of your application’s access control decisions in a Lambda function, making it easier to manage your application security.

The possibilities of the Sense HAT

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/sense-hat-projects/

Did you realise the Sense HAT has been available for over two years now? Used by astronauts on the International Space Station, the exact same hardware is available to you on Earth. With a new Astro Pi challenge just launched, it’s time for a retrospective/roundup/inspiration post about this marvellous bit of kit.

Sense HAT attached to Pi and power cord

The Sense HAT on a Pi in full glory

The Sense HAT explained

We developed our scientific add-on board to be part of the Astro Pi computers we sent to the International Space Station with ESA astronaut Tim Peake. For a play-by-play of Astro Pi’s history, head to the blog archive.

Astro Pi logo with starry background

Just to remind you, this is all the cool stuff our engineers have managed to fit onto the HAT:

  • A gyroscope (sensing pitch, roll, and yaw)
  • An accelerometer
  • A magnetometer
  • Sensors for temperature, humidity, and barometric pressure
  • A joystick
  • An 8×8 LED matrix

You can find a roundup of the technical specs here on the blog.

How to Sense HAT

It’s easy to begin exploring this device: take a look at our free Getting started with the Sense HAT resource, or use one of our Code Club Sense HAT projects. You can also try out the emulator, available offline on Raspbian and online on Trinket.

Sense HAT emulator on Trinket

The Sense HAT emulator on trinket.io

Fun and games with the Sense HAT

Use the LED matrix and joystick to recreate games such as Pong or Flappy Bird. Of course, you could also add sensor input to your game: code an egg drop game or a Magic 8 Ball that reacts to how the device moves.

Sense HAT Random Sparkles

Create random sparkles on the Sense HAT

Once December rolls around, you could brighten up your home with a voice-controlled Christmas tree or an advent calendar on your Sense HAT.

If you like the great outdoors, you could also use your Sense HAT to recreate this Hiking Companion by Marcus Johnson. Take it with you on your next hike!

Art with the Sense HAT

The LED matrix is perfect for getting creative. To draw something basic without having to squint at a Python list, use this app by our very own Richard Hayler. Feeling more ambitious? The MagPi will teach you how to create magnificent pixel art. Ben Nuttall has created this neat little Python script for displaying a photo taken by the Raspberry Pi Camera Module on the Sense HAT.

Brett Haines Mathematica on the Sense HAT

It’s also possible to incorporate Sense HAT data into your digital art! The Python Turtle module and the Processing language are both useful tools for creating beautiful animations based on real-world information.

A Sense HAT project that also uses this principle is Giorgio Sancristoforo’s Tableau, a ‘generative music album’. This device creates music according to the sensor data:

Tableau Generative Album

“There is no doubt that, as music is removed by the phonographrecord from the realm of live production and from the imperative of artistic activity and becomes petrified, it absorbs into itself, in this process of petrification, the very life that would otherwise vanish.”

Science with the Sense HAT

This free Essentials book from The MagPi team covers all the Sense HAT science basics. You can, for example, learn how to measure gravity.

Cropped cover of Experiment with the Sense HAT book

Our online resource shows you how to record the information your HAT picks up. Next you can analyse and graph your data using Mathematica, which is included for free on Raspbian. This resource walks you through how this software works.

If you’re seeking inspiration for experiments you can do on our Astro Pis Izzy and Ed on the ISS, check out the winning entries of previous rounds of the Astro Pi challenge.

Thomas Pesquet with Ed and Izzy

Thomas Pesquet with Ed and Izzy

But you can also stick to terrestrial scientific investigations. For example, why not build a weather station and share its data on your own web server or via Weather Underground?

Your code in space!

If you’re a student or an educator in one of the 22 ESA member states, you can get a team together to enter our 2017-18 Astro Pi challenge. There are two missions to choose from, including Mission Zero: follow a few guidelines, and your code is guaranteed to run in space!

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Security updates for Monday

Post Syndicated from ris original https://lwn.net/Articles/734761/rss

Security updates have been issued by Debian (bzr, clamav, libgd2, libraw, samba, and tomcat7), Fedora (drupal7-views, gnome-shell, httpd, krb5, libmspack, LibRaw, mingw-LibRaw, mpg123, pkgconf, python-jwt, and samba), Gentoo (adobe-flash, chromium, cvs, exim, mercurial, oracle-jdk-bin, php, postfix, and tcpdump), openSUSE (Chromium and libraw), Red Hat (chromium-browser), and Slackware (libxml2 and python).

Announcing the 2017-18 European Astro Pi challenge!

Post Syndicated from David Honess original https://www.raspberrypi.org/blog/announcing-2017-18-astro-pi/

Astro Pi is back! Today we’re excited to announce the 2017-18 European Astro Pi challenge in partnership with the European Space Agency (ESA). We are searching for the next generation of space scientists.

YouTube

Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube.

Astro Pi is an annual science and coding competition where student-written code is run on the International Space Station under the oversight of an ESA astronaut. The challenge is open to students from all 22 ESA member countries, including — for the first time — associate members Canada and Slovenia.

The format of the competition is changing slightly this year, and we also have a brand-new non-competitive mission in which participants are guaranteed to have their code run on the ISS for 30 seconds!

Mission Zero

Until now, students have worked on Astro Pi projects in an extra-curricular context and over multiple sessions. For teachers and students who don’t have much spare capacity, we wanted to provide an accessible activity that teams can complete in just one session.

So we came up with Mission Zero for young people no older than 14. To complete it, form a team of two to four people and use our step-by-step guide to help you write a simple Python program that shows your personal message and the ambient temperature on the Astro Pi. If you adhere to a few rules, your code is guaranteed to run in space for 30 seconds, and you’ll receive a certificate showing the exact time period during which your code has run in space. No special hardware is needed for this mission, since everything is done in a web browser.

Mission Zero is open until 26 November 2017! Find out more.

Mission Space Lab

Students aged up to 19 can take part in Mission Space Lab. Form a team of two to six people, and work like real space scientists to design your own experiment. Receive free kit to work with, and write the Python code to carry out your experiment.

There are two themes for Mission Space Lab teams to choose from for their projects:

  • Life in space
    You will make use of Astro Pi Vis (“Ed”) in the European Columbus module. You can use all of its sensors, but you cannot record images or videos.
  • Life on Earth
    You will make use of Astro Pi IR (“Izzy”), which will be aimed towards the Earth through a window. You can use all of its sensors and its camera.

The Astro Pi kit, delivered to Space Lab teams by ESA

If you achieve flight status, your code will be uploaded to the ISS and run for three hours (two orbits). All the data that your code records in space will be downloaded and returned to you for analysis. Then submit a short report on your findings to be in with a chance to win exclusive, money-can’t-buy prizes! You can also submit your project for a Bronze CREST Award.

Mission Space Lab registration is open until 29 October 2017, and accepted teams will continue to spring 2018. Find out more.

How do I get started?

There are loads of materials available that will help you begin your Astro Pi journey — check out the Getting started with the Sense HAT resource and this video explaining how to build the flight case.

Questions?

If you have any questions, please post them in the comments below. We’re standing by to answer them!

The post Announcing the 2017-18 European Astro Pi challenge! appeared first on Raspberry Pi.

Dialekt-o-maten vending machine

Post Syndicated from Janina Ander original https://www.raspberrypi.org/blog/dialekt-o-maten-vending-machine/

At some point, many of you will have become exasperated with your AI personal assistant for not understanding you due to your accent – or worse, your fantastic regional dialect! A vending machine from Coca-Cola Sweden turns this issue inside out: the Dialekt-o-maten rewards users with a free soft drink for speaking in a Swedish regional dialect.

The world’s first vending machine where you pay with a dialect!

Thirsty fans along with journalists were invited to try Dialekt-o-maten at Stureplan in central Stockholm. Depending on how well they could pronounce the different phrases in assorted Swedish dialects – they were rewarded an ice cold Coke with that destination on the label.

The Dialekt-o-maten

The machine, which uses a Raspberry Pi, was set up in Stureplan Square in Stockholm. A person presses one of six buttons to choose the regional dialect they want to try out. They then hit ‘record’, and speak into the microphone. The recording is compared to a library of dialect samples, and, if it matches closely enough, voila! — the Dialekt-o-maten dispenses a soft drink for free.

Dialekt-o-maten on the highstreet in Stockholm

Code for the Dialekt-o-maten

The team of developers used the dejavu Python library, as well as custom-written code which responded to new recordings. Carl-Anders Svedberg, one of the developers, said:

Testing the voices and fine-tuning the right level of difficulty for the users was quite tricky. And we really should have had more voice samples. Filtering out noise from the surroundings, like cars and music, was also a small hurdle.

While they wrote the initial software on macOS, the team transferred it to a Raspberry Pi so they could install the hardware inside the Dialekt-o-maten.

Regional dialects

Even though Sweden has only ten million inhabitants, there are more than 100 Swedish dialects. In some areas of Sweden, the local language even still resembles Old Norse. The Dialekt-o-maten recorded how well people spoke the six dialects it used. Apparently, the hardest one to imitate is spoken in Vadstena, and the easiest is spoken in Smögen.

Dialekt-o-maten on Stockholm highstreet

Speech recognition with the Pi

Because of its audio input capabilities, the Raspberry Pi is very useful for building devices that use speech recognition software. One of our favourite projects in this vein is of course Allen Pan’s Real-Life Wizard Duel. We also think this pronunciation training machine by Japanese makers HomeMadeGarbage is really neat. Ideas from these projects and the Dialekt-o-maten could potentially be combined to make a fully fledged language-learning tool!

How about you? Have you used a Raspberry Pi to help you become multilingual? If so, do share your project with us in the comments or via social media.

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