Tag Archives: javascript

Implementing Default Directory Indexes in Amazon S3-backed Amazon CloudFront Origins Using [email protected]

Post Syndicated from Ronnie Eichler original https://aws.amazon.com/blogs/compute/implementing-default-directory-indexes-in-amazon-s3-backed-amazon-cloudfront-origins-using-lambdaedge/

With the recent launch of [email protected], it’s now possible for you to provide even more robust functionality to your static websites. Amazon CloudFront is a content distribution network service. In this post, I show how you can use [email protected] along with the CloudFront origin access identity (OAI) for Amazon S3 and still provide simple URLs (such as www.example.com/about/ instead of www.example.com/about/index.html).

Background

Amazon S3 is a great platform for hosting a static website. You don’t need to worry about managing servers or underlying infrastructure—you just publish your static to content to an S3 bucket. S3 provides a DNS name such as <bucket-name>.s3-website-<AWS-region>.amazonaws.com. Use this name for your website by creating a CNAME record in your domain’s DNS environment (or Amazon Route 53) as follows:

www.example.com -> <bucket-name>.s3-website-<AWS-region>.amazonaws.com

You can also put CloudFront in front of S3 to further scale the performance of your site and cache the content closer to your users. CloudFront can enable HTTPS-hosted sites, by either using a custom Secure Sockets Layer (SSL) certificate or a managed certificate from AWS Certificate Manager. In addition, CloudFront also offers integration with AWS WAF, a web application firewall. As you can see, it’s possible to achieve some robust functionality by using S3, CloudFront, and other managed services and not have to worry about maintaining underlying infrastructure.

One of the key concerns that you might have when implementing any type of WAF or CDN is that you want to force your users to go through the CDN. If you implement CloudFront in front of S3, you can achieve this by using an OAI. However, in order to do this, you cannot use the HTTP endpoint that is exposed by S3’s static website hosting feature. Instead, CloudFront must use the S3 REST endpoint to fetch content from your origin so that the request can be authenticated using the OAI. This presents some challenges in that the REST endpoint does not support redirection to a default index page.

CloudFront does allow you to specify a default root object (index.html), but it only works on the root of the website (such as http://www.example.com > http://www.example.com/index.html). It does not work on any subdirectory (such as http://www.example.com/about/). If you were to attempt to request this URL through CloudFront, CloudFront would do a S3 GetObject API call against a key that does not exist.

Of course, it is a bad user experience to expect users to always type index.html at the end of every URL (or even know that it should be there). Until now, there has not been an easy way to provide these simpler URLs (equivalent to the DirectoryIndex Directive in an Apache Web Server configuration) to users through CloudFront. Not if you still want to be able to restrict access to the S3 origin using an OAI. However, with the release of [email protected], you can use a JavaScript function running on the CloudFront edge nodes to look for these patterns and request the appropriate object key from the S3 origin.

Solution

In this example, you use the compute power at the CloudFront edge to inspect the request as it’s coming in from the client. Then re-write the request so that CloudFront requests a default index object (index.html in this case) for any request URI that ends in ‘/’.

When a request is made against a web server, the client specifies the object to obtain in the request. You can use this URI and apply a regular expression to it so that these URIs get resolved to a default index object before CloudFront requests the object from the origin. Use the following code:

'use strict';
exports.handler = (event, context, callback) => {
    
    // Extract the request from the CloudFront event that is sent to [email protected] 
    var request = event.Records[0].cf.request;

    // Extract the URI from the request
    var olduri = request.uri;

    // Match any '/' that occurs at the end of a URI. Replace it with a default index
    var newuri = olduri.replace(/\/$/, '\/index.html');
    
    // Log the URI as received by CloudFront and the new URI to be used to fetch from origin
    console.log("Old URI: " + olduri);
    console.log("New URI: " + newuri);
    
    // Replace the received URI with the URI that includes the index page
    request.uri = newuri;
    
    // Return to CloudFront
    return callback(null, request);

};

To get started, create an S3 bucket to be the origin for CloudFront:

Create bucket

On the other screens, you can just accept the defaults for the purposes of this walkthrough. If this were a production implementation, I would recommend enabling bucket logging and specifying an existing S3 bucket as the destination for access logs. These logs can be useful if you need to troubleshoot issues with your S3 access.

Now, put some content into your S3 bucket. For this walkthrough, create two simple webpages to demonstrate the functionality:  A page that resides at the website root, and another that is in a subdirectory.

<s3bucketname>/index.html

<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Root home page</title>
    </head>
    <body>
        <p>Hello, this page resides in the root directory.</p>
    </body>
</html>

<s3bucketname>/subdirectory/index.html

<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Subdirectory home page</title>
    </head>
    <body>
        <p>Hello, this page resides in the /subdirectory/ directory.</p>
    </body>
</html>

When uploading the files into S3, you can accept the defaults. You add a bucket policy as part of the CloudFront distribution creation that allows CloudFront to access the S3 origin. You should now have an S3 bucket that looks like the following:

Root of bucket

Subdirectory in bucket

Next, create a CloudFront distribution that your users will use to access the content. Open the CloudFront console, and choose Create Distribution. For Select a delivery method for your content, under Web, choose Get Started.

On the next screen, you set up the distribution. Below are the options to configure:

  • Origin Domain Name:  Select the S3 bucket that you created earlier.
  • Restrict Bucket Access: Choose Yes.
  • Origin Access Identity: Create a new identity.
  • Grant Read Permissions on Bucket: Choose Yes, Update Bucket Policy.
  • Object Caching: Choose Customize (I am changing the behavior to avoid having CloudFront cache objects, as this could affect your ability to troubleshoot while implementing the Lambda code).
    • Minimum TTL: 0
    • Maximum TTL: 0
    • Default TTL: 0

You can accept all of the other defaults. Again, this is a proof-of-concept exercise. After you are comfortable that the CloudFront distribution is working properly with the origin and Lambda code, you can re-visit the preceding values and make changes before implementing it in production.

CloudFront distributions can take several minutes to deploy (because the changes have to propagate out to all of the edge locations). After that’s done, test the functionality of the S3-backed static website. Looking at the distribution, you can see that CloudFront assigns a domain name:

CloudFront Distribution Settings

Try to access the website using a combination of various URLs:

http://<domainname>/:  Works

› curl -v http://d3gt20ea1hllb.cloudfront.net/
*   Trying 54.192.192.214...
* TCP_NODELAY set
* Connected to d3gt20ea1hllb.cloudfront.net (54.192.192.214) port 80 (#0)
> GET / HTTP/1.1
> Host: d3gt20ea1hllb.cloudfront.net
> User-Agent: curl/7.51.0
> Accept: */*
>
< HTTP/1.1 200 OK
< ETag: "cb7e2634fe66c1fd395cf868087dd3b9"
< Accept-Ranges: bytes
< Server: AmazonS3
< X-Cache: Miss from cloudfront
< X-Amz-Cf-Id: -D2FSRwzfcwyKZKFZr6DqYFkIf4t7HdGw2MkUF5sE6YFDxRJgi0R1g==
< Content-Length: 209
< Content-Type: text/html
< Last-Modified: Wed, 19 Jul 2017 19:21:16 GMT
< Via: 1.1 6419ba8f3bd94b651d416054d9416f1e.cloudfront.net (CloudFront), 1.1 iad6-proxy-3.amazon.com:80 (Cisco-WSA/9.1.2-010)
< Connection: keep-alive
<
<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Root home page</title>
    </head>
    <body>
        <p>Hello, this page resides in the root directory.</p>
    </body>
</html>
* Curl_http_done: called premature == 0
* Connection #0 to host d3gt20ea1hllb.cloudfront.net left intact

This is because CloudFront is configured to request a default root object (index.html) from the origin.

http://<domainname>/subdirectory/:  Doesn’t work

› curl -v http://d3gt20ea1hllb.cloudfront.net/subdirectory/
*   Trying 54.192.192.214...
* TCP_NODELAY set
* Connected to d3gt20ea1hllb.cloudfront.net (54.192.192.214) port 80 (#0)
> GET /subdirectory/ HTTP/1.1
> Host: d3gt20ea1hllb.cloudfront.net
> User-Agent: curl/7.51.0
> Accept: */*
>
< HTTP/1.1 200 OK
< ETag: "d41d8cd98f00b204e9800998ecf8427e"
< x-amz-server-side-encryption: AES256
< Accept-Ranges: bytes
< Server: AmazonS3
< X-Cache: Miss from cloudfront
< X-Amz-Cf-Id: Iqf0Gy8hJLiW-9tOAdSFPkL7vCWBrgm3-1ly5tBeY_izU82ftipodA==
< Content-Length: 0
< Content-Type: application/x-directory
< Last-Modified: Wed, 19 Jul 2017 19:21:24 GMT
< Via: 1.1 6419ba8f3bd94b651d416054d9416f1e.cloudfront.net (CloudFront), 1.1 iad6-proxy-3.amazon.com:80 (Cisco-WSA/9.1.2-010)
< Connection: keep-alive
<
* Curl_http_done: called premature == 0
* Connection #0 to host d3gt20ea1hllb.cloudfront.net left intact

If you use a tool such like cURL to test this, you notice that CloudFront and S3 are returning a blank response. The reason for this is that the subdirectory does exist, but it does not resolve to an S3 object. Keep in mind that S3 is an object store, so there are no real directories. User interfaces such as the S3 console present a hierarchical view of a bucket with folders based on the presence of forward slashes, but behind the scenes the bucket is just a collection of keys that represent stored objects.

http://<domainname>/subdirectory/index.html:  Works

› curl -v http://d3gt20ea1hllb.cloudfront.net/subdirectory/index.html
*   Trying 54.192.192.130...
* TCP_NODELAY set
* Connected to d3gt20ea1hllb.cloudfront.net (54.192.192.130) port 80 (#0)
> GET /subdirectory/index.html HTTP/1.1
> Host: d3gt20ea1hllb.cloudfront.net
> User-Agent: curl/7.51.0
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Thu, 20 Jul 2017 20:35:15 GMT
< ETag: "ddf87c487acf7cef9d50418f0f8f8dae"
< Accept-Ranges: bytes
< Server: AmazonS3
< X-Cache: RefreshHit from cloudfront
< X-Amz-Cf-Id: bkh6opXdpw8pUomqG3Qr3UcjnZL8axxOH82Lh0OOcx48uJKc_Dc3Cg==
< Content-Length: 227
< Content-Type: text/html
< Last-Modified: Wed, 19 Jul 2017 19:21:45 GMT
< Via: 1.1 3f2788d309d30f41de96da6f931d4ede.cloudfront.net (CloudFront), 1.1 iad6-proxy-3.amazon.com:80 (Cisco-WSA/9.1.2-010)
< Connection: keep-alive
<
<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Subdirectory home page</title>
    </head>
    <body>
        <p>Hello, this page resides in the /subdirectory/ directory.</p>
    </body>
</html>
* Curl_http_done: called premature == 0
* Connection #0 to host d3gt20ea1hllb.cloudfront.net left intact

This request works as expected because you are referencing the object directly. Now, you implement the [email protected] function to return the default index.html page for any subdirectory. Looking at the example JavaScript code, here’s where the magic happens:

var newuri = olduri.replace(/\/$/, '\/index.html');

You are going to use a JavaScript regular expression to match any ‘/’ that occurs at the end of the URI and replace it with ‘/index.html’. This is the equivalent to what S3 does on its own with static website hosting. However, as I mentioned earlier, you can’t rely on this if you want to use a policy on the bucket to restrict it so that users must access the bucket through CloudFront. That way, all requests to the S3 bucket must be authenticated using the S3 REST API. Because of this, you implement a [email protected] function that takes any client request ending in ‘/’ and append a default ‘index.html’ to the request before requesting the object from the origin.

In the Lambda console, choose Create function. On the next screen, skip the blueprint selection and choose Author from scratch, as you’ll use the sample code provided.

Next, configure the trigger. Choosing the empty box shows a list of available triggers. Choose CloudFront and select your CloudFront distribution ID (created earlier). For this example, leave Cache Behavior as * and CloudFront Event as Origin Request. Select the Enable trigger and replicate box and choose Next.

Lambda Trigger

Next, give the function a name and a description. Then, copy and paste the following code:

'use strict';
exports.handler = (event, context, callback) => {
    
    // Extract the request from the CloudFront event that is sent to [email protected] 
    var request = event.Records[0].cf.request;

    // Extract the URI from the request
    var olduri = request.uri;

    // Match any '/' that occurs at the end of a URI. Replace it with a default index
    var newuri = olduri.replace(/\/$/, '\/index.html');
    
    // Log the URI as received by CloudFront and the new URI to be used to fetch from origin
    console.log("Old URI: " + olduri);
    console.log("New URI: " + newuri);
    
    // Replace the received URI with the URI that includes the index page
    request.uri = newuri;
    
    // Return to CloudFront
    return callback(null, request);

};

Next, define a role that grants permissions to the Lambda function. For this example, choose Create new role from template, Basic Edge Lambda permissions. This creates a new IAM role for the Lambda function and grants the following permissions:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "logs:CreateLogGroup",
                "logs:CreateLogStream",
                "logs:PutLogEvents"
            ],
            "Resource": [
                "arn:aws:logs:*:*:*"
            ]
        }
    ]
}

In a nutshell, these are the permissions that the function needs to create the necessary CloudWatch log group and log stream, and to put the log events so that the function is able to write logs when it executes.

After the function has been created, you can go back to the browser (or cURL) and re-run the test for the subdirectory request that failed previously:

› curl -v http://d3gt20ea1hllb.cloudfront.net/subdirectory/
*   Trying 54.192.192.202...
* TCP_NODELAY set
* Connected to d3gt20ea1hllb.cloudfront.net (54.192.192.202) port 80 (#0)
> GET /subdirectory/ HTTP/1.1
> Host: d3gt20ea1hllb.cloudfront.net
> User-Agent: curl/7.51.0
> Accept: */*
>
< HTTP/1.1 200 OK
< Date: Thu, 20 Jul 2017 21:18:44 GMT
< ETag: "ddf87c487acf7cef9d50418f0f8f8dae"
< Accept-Ranges: bytes
< Server: AmazonS3
< X-Cache: Miss from cloudfront
< X-Amz-Cf-Id: rwFN7yHE70bT9xckBpceTsAPcmaadqWB9omPBv2P6WkIfQqdjTk_4w==
< Content-Length: 227
< Content-Type: text/html
< Last-Modified: Wed, 19 Jul 2017 19:21:45 GMT
< Via: 1.1 3572de112011f1b625bb77410b0c5cca.cloudfront.net (CloudFront), 1.1 iad6-proxy-3.amazon.com:80 (Cisco-WSA/9.1.2-010)
< Connection: keep-alive
<
<!doctype html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Subdirectory home page</title>
    </head>
    <body>
        <p>Hello, this page resides in the /subdirectory/ directory.</p>
    </body>
</html>
* Curl_http_done: called premature == 0
* Connection #0 to host d3gt20ea1hllb.cloudfront.net left intact

You have now configured a way for CloudFront to return a default index page for subdirectories in S3!

Summary

In this post, you used [email protected] to be able to use CloudFront with an S3 origin access identity and serve a default root object on subdirectory URLs. To find out some more about this use-case, see [email protected] integration with CloudFront in our documentation.

If you have questions or suggestions, feel free to comment below. For troubleshooting or implementation help, check out the Lambda forum.

Pirate Bay is Mining Cryptocurrency Again, No Opt Out

Post Syndicated from Ernesto original https://torrentfreak.com/pirate-bay-is-mining-cryptocurrency-again-no-opt-out-171011/

Last month The Pirate Bay caused some uproar by adding a Javascript-based cryptocurrency miner to its website.

The miner utilizes CPU power from visitors to generate Monero coins for the site, providing an extra source of revenue.

The Pirate Bay only tested the option briefly, but that was enough to inspire many others to follow suit. Now, a few weeks later, Pirate Bay has also turned on the miners again.

The miner is not directly embedded in the site’s core code but runs through an ad script. Many ad blockers and anti-malware tools are stopping these request, but people who don’t use any will see a clear spike in CPU usage when they access the site.

The Pirate Bay team previously said that they were testing the miner to see if it can replace ads. While there is some real revenue potential, for now, it’s running in addition to the regular banners. It’s unclear whether the current mining period is another test or if it will run permanently from now on.

The miner does appear to be throttled to a certain degree, so most users might not even notice that it’s running.

Pirate Bay load requests

Running a cryptocurrency miner such as the Coin-Hive script TPB is currently using is not without risk. Aside from user complaints, there is an issue that may make it harder for the site to operate in the future.

Last week we reported that CDN provider Cloudflare had suspended the account of torrent proxy site ProxyBunker, flagging its coin miner as malware. This means that The Pirate Bay now risks losing the Cloudflare service, which they rely on for DDoS protection, among other things.

Cloudflare’s suspension of ProxyBunker occurred even though the site provided users with an option to disable the miner. This functionality was implemented by Coinhive after the script was misused by some sites, which ran it without alerting their users.

The Pirate Bay currently has no opt-out option, nor has it informed users about the latest mining efforts. This could lead to another problem since Coinhive said it would crack down on customers who failed to keep users in the loop.

“We will verify this opt-in on our servers and will implement it in a way that it can not be circumvented. We will pledge to keep the opt-in intact at all times, without exceptions,” the Coinhive team previously noted.

The Pirate Bay team has not commented on the issue thus far. In theory, it’s possible that a rogue advertiser is responsible for the latest mining efforts. If that’s the case it will be disabled soon enough.

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

Weekly roundup: Slow start

Post Syndicated from Eevee original https://eev.ee/dev/2017/10/08/weekly-roundup-slow-start/

Getting back up to speed, finishing getting my computer back how it was, etc. Also we got a SNES Classic and Stardew Valley so, those have been things. But between all that, I somehow found time to do a microscopic amount of actual work!

  • art: Sketched some stuff! It wasn’t very good. Need to do this more often.

  • fox flux: Finally, after a great many attempts, I drew a pixel art bush I’m fairly happy with. And yet, I can already see ways to improve it! But hey I’m learning stuff and that’s really cool. I’ve been working on a much larger pixel art forest background, too, which is proving a little harder to figure out.

  • blog: After a long period of silence, I wrote about how JavaScript has gotten a bit better lately. More words to come, probably!

I’ve got some high aspirations for the month, so I’m gonna get to it and definitely not go visit my video game chickens.

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:

1
<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:

1
2
3
4
5
6
// 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:

1
2
3
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5
6
7
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:

1
2
3
4
5
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7
8
9
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?

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{
    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.

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[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.

Cloudflare Bans Sites For Using Cryptocurrency Miners

Post Syndicated from Andy original https://torrentfreak.com/cloudflare-bans-sites-for-using-cryptocurrency-miners-171004/

After years of accepting donations via Bitcoin, last month various ‘pirate’ sites began to generate digital currency revenues in a brand new way.

It all began with The Pirate Bay, which quietly added a Javascript cryptocurrency miner to its main site, something that first manifested itself as a large spike in CPU utilization on the machines of visitors.

The stealth addition to the platform, which its operators later described as a test, was extremely controversial. While many thought of the miner as a cool and innovative way to generate revenue in a secure fashion, a vocal majority expressed a preference for permission being requested first, in case they didn’t want to participate in the program.

Over the past couple of weeks, several other sites have added similar miners, some which ask permission to run and others that do not. While the former probably aren’t considered problematic, the latter are now being viewed as a serious problem by an unexpected player in the ecosystem.

TorrentFreak has learned that popular CDN service Cloudflare, which is often criticized for not being harsh enough on ‘pirate’ sites, is actively suspending the accounts of sites that deploy cryptocurrency miners on their platforms.

“Cloudflare kicked us from their service for using a Coinhive miner,” the operator of ProxyBunker.online informed TF this morning.

ProxyBunker is a site that that links to several other domains that offer unofficial proxy services for the likes of The Pirate Bay, RARBG, KickassTorrents, Torrentz2, and dozens of other sites. It first tested a miner for four days starting September 23. Official implementation began October 1 but was ended last evening, abruptly.

“Late last night, all our domains got deleted off Cloudflare without warning so I emailed Cloudflare to ask what was going on,” the operator explained.

Bye bye

As the email above shows, Cloudflare cited only a “possible” terms of service violation. Further clarification was needed to get to the root of the problem.

So, just a few minutes later, the site operator contacted Cloudflare, acknowledging the suspension but pointing out that the notification email was somewhat vague and didn’t give a reason for the violation. A follow-up email from Cloudflare certainly put some meat on the bones.

“Multiple domains in your account were injecting Coinhive mining code without
notifying users and without any option to disabling [sic] the mining,” wrote Justin Paine, Head of Trust & Safety at Cloudflare.

“We consider this to be malware, and as such the account was suspended, and all domains removed from Cloudflare.”

Cloudflare: Unannounced miners are malware

ProxyBunker’s operator wrote back to Cloudflare explaining that the Coinhive miner had been running on his domains but that his main domain had a way of disabling mining, as per new code made available from Coinhive.

“We were running the miner on our proxybunker.online domain using Coinhive’s new Javacode Simple Miner UI that lets the user stop the miner at anytime and set the CPU speed it mines at,” he told TF.

Nevertheless, some element of the configuration appears to have fallen short of Cloudflare’s standards. So, shortly after Cloudflare’s explanation, the site operator asked if he could be reinstated if he completely removed the miner from his site. The response was a ‘yes’ but with a stern caveat attached.

“We will remove the account suspension, however do note you’ll need to re-sign up the domains as they were removed as a result of the account suspension. Please note — if we discover similar activity again the domains and account will be permanently blocked,” Cloudflare’s Justin warned.

ProxyBunker’s operator says that while he sees the value in cryptocurrency miners, he can understand why people might be opposed to them too. That being said, he would appreciate it if services like Cloudflare published clear guidelines on what is and is not acceptable.

“We do understand that most users will not like the miner using up a bit of their CPU but we do see the full potential as a new revenue stream,” he explains.

“I think third-party services need to post clear information that they’re not allowed on their services, if that’s the case.”

At time of publication, Cloudflare had not responded to TorrentFreak’s requests for comment.

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

Backing Up WordPress

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/backing-up-wordpress/

WordPress cloud backup
WordPress logo

WordPress is the most popular CMS (Content Management System) for websites, with almost 30% of all websites in the world using WordPress. That’s a lot of sites — over 350 million!

In this post we’ll talk about the different approaches to keeping the data on your WordPress website safe.


Stop the Presses! (Or the Internet!)

As we were getting ready to publish this post, we received news from UpdraftPlus, one of the biggest WordPress plugin developers, that they are supporting Backblaze B2 as a storage solution for their backup plugin. They shipped the update (1.13.9) this week. This is great news for Backblaze customers! UpdraftPlus is also offering a 20% discount to Backblaze customers wishing to purchase or upgrade to UpdraftPlus Premium. The complete information is below.

UpdraftPlus joins backup plugin developer XCloner — Backup and Restore in supporting Backblaze B2. A third developer, BlogVault, also announced their intent to support Backblaze B2. Contact your favorite WordPress backup plugin developer and urge them to support Backblaze B2, as well.

Now, back to our post…


Your WordPress website data is on a web server that’s most likely located in a large data center. You might wonder why it is necessary to have a backup of your website if it’s in a data center. Website data can be lost in a number of ways, including mistakes by the website owner (been there), hacking, or even domain ownership dispute (I’ve seen it happen more than once). A website backup also can provide a history of changes you’ve made to the website, which can be useful. As an overall strategy, it’s best to have a backup of any data that you can’t afford to lose for personal or business reasons.

Your web hosting company might provide backup services as part of your hosting plan. If you are using their service, you should know where and how often your data is being backed up. You don’t want to find out too late that your backup plan was not adequate.

Sites on WordPress.com are automatically backed up by VaultPress (Automattic), which also is available for self-hosted WordPress installations. If you don’t want the work or decisions involved in managing the hosting for your WordPress site, WordPress.com will handle it for you. You do, however, give up some customization abilities, such as the option to add plugins of your own choice.

Very large and active websites might consider WordPress VIP by Automattic, or another premium WordPress hosting service such as Pagely.com.

This post is about backing up self-hosted WordPress sites, so we’ll focus on those options.

WordPress Backup

Backup strategies for WordPress can be divided into broad categories depending on 1) what you back up, 2) when you back up, and 3) where the data is backed up.

With server data, such as with a WordPress installation, you should plan to have three copies of the data (the 3-2-1 backup strategy). The first is the active data on the WordPress web server, the second is a backup stored on the web server or downloaded to your local computer, and the third should be in another location, such as the cloud.

We’ll talk about the different approaches to backing up WordPress, but we recommend using a WordPress plugin to handle your backups. A backup plugin can automate the task, optimize your backup storage space, and alert you of problems with your backups or WordPress itself. We’ll cover plugins in more detail, below.

What to Back Up?

The main components of your WordPress installation are:

You should decide which of these elements you wish to back up. The database is the top priority, as it contains all your website posts and pages (exclusive of media). Your current theme is important, as it likely contains customizations you’ve made. Following those in priority are any other files you’ve customized or made changes to.

You can choose to back up the WordPress core installation and plugins, if you wish, but these files can be downloaded again if necessary from the source, so you might not wish to include them. You likely have all the media files you use on your website on your local computer (which should be backed up), so it is your choice whether to back these up from the server as well.

If you wish to be able to recreate your entire website easily in case of data loss or disaster, you might choose to back up everything, though on a large website this could be a lot of data.

Generally, you should 1) prioritize any file that you’ve customized that you can’t afford to lose, and 2) decide whether you need a copy of everything in order to get your site back up quickly. These choices will determine your backup method and the amount of storage you need.

A good backup plugin for WordPress enables you to specify which files you wish to back up, and even to create separate backups and schedules for different backup contents. That’s another good reason to use a plugin for backing up WordPress.

When to Back Up?

You can back up manually at any time by using the Export tool in WordPress. This is handy if you wish to do a quick backup of your site or parts of it. Since it is manual, however, it is not a part of a dependable backup plan that should be done regularly. If you wish to use this tool, go to Tools, Export, and select what you wish to back up. The output will be an XML file that uses the WordPress Extended RSS format, also known as WXR. You can create a WXR file that contains all of the information on your site or just portions of the site, such as posts or pages by selecting: All content, Posts, Pages, or Media.
Note: You can use WordPress’s Export tool for sites hosted on WordPress.com, as well.

Export instruction for WordPress

Many of the backup plugins we’ll be discussing later also let you do a manual backup on demand in addition to regularly scheduled or continuous backups.

Note:  Another use of the WordPress Export tool and the WXR file is to transfer or clone your website to another server. Once you have exported the WXR file from the website you wish to transfer from, you can import the WXR file from the Tools, Import menu on the new WordPress destination site. Be aware that there are file size limits depending on the settings on your web server. See the WordPress Codex entry for more information. To make this job easier, you may wish to use one of a number of WordPress plugins designed specifically for this task.

You also can manually back up the WordPress MySQL database using a number of tools or a plugin. The WordPress Codex has good information on this. All WordPress plugins will handle this for you and do it automatically. They also typically include tools for optimizing the database tables, which is just good housekeeping.

A dependable backup strategy doesn’t rely on manual backups, which means you should consider using one of the many backup plugins available either free or for purchase. We’ll talk more about them below.

Which Format To Back Up In?

In addition to the WordPress WXR format, plugins and server tools will use various file formats and compression algorithms to store and compress your backup. You may get to choose between zip, tar, tar.gz, tar.gz2, and others. See The Most Common Archive File Formats for more information on these formats.

Select a format that you know you can access and unarchive should you need access to your backup. All of these formats are standard and supported across operating systems, though you might need to download a utility to access the file.

Where To Back Up?

Once you have your data in a suitable format for backup, where do you back it up to?

We want to have multiple copies of our active website data, so we’ll choose more than one destination for our backup data. The backup plugins we’ll discuss below enable you to specify one or more possible destinations for your backup. The possible destinations for your backup include:

A backup folder on your web server
A backup folder on your web server is an OK solution if you also have a copy elsewhere. Depending on your hosting plan, the size of your site, and what you include in the backup, you may or may not have sufficient disk space on the web server. Some backup plugins allow you to configure the plugin to keep only a certain number of recent backups and delete older ones, saving you disk space on the server.
Email to you
Because email servers have size limitations, the email option is not the best one to use unless you use it to specifically back up just the database or your main theme files.
FTP, SFTP, SCP, WebDAV
FTP, SFTP, SCP, and WebDAV are all widely-supported protocols for transferring files over the internet and can be used if you have access credentials to another server or supported storage device that is suitable for storing a backup.
Sync service (Dropbox, SugarSync, Google Drive, OneDrive)
A sync service is another possible server storage location though it can be a pricier choice depending on the plan you have and how much you wish to store.
Cloud storage (Backblaze B2, Amazon S3, Google Cloud, Microsoft Azure, Rackspace)
A cloud storage service can be an inexpensive and flexible option with pay-as-you go pricing for storing backups and other data.

A good website backup strategy would be to have multiple backups of your website data: one in a backup folder on your web hosting server, one downloaded to your local computer, and one in the cloud, such as with Backblaze B2.

If I had to choose just one of these, I would choose backing up to the cloud because it is geographically separated from both your local computer and your web host, it uses fault-tolerant and redundant data storage technologies to protect your data, and it is available from anywhere if you need to restore your site.

Backup Plugins for WordPress

Probably the easiest and most common way to implement a solid backup strategy for WordPress is to use one of the many backup plugins available for WordPress. Fortunately, there are a number of good ones and are available free or in “freemium” plans in which you can use the free version and pay for more features and capabilities only if you need them. The premium options can give you more flexibility in configuring backups or have additional options for where you can store the backups.

How to Choose a WordPress Backup Plugin

screenshot of WordPress plugins search

When considering which plugin to use, you should take into account a number of factors in making your choice.

Is the plugin actively maintained and up-to-date? You can determine this from the listing in the WordPress Plugin Repository. You also can look at reviews and support comments to get an idea of user satisfaction and how well issues are resolved.

Does the plugin work with your web hosting provider? Generally, well-supported plugins do, but you might want to check to make sure there are no issues with your hosting provider.

Does it support the cloud service or protocol you wish to use? This can be determined from looking at the listing in the WordPress Plugin Repository or on the developer’s website. Developers often will add support for cloud services or other backup destinations based on user demand, so let the developer know if there is a feature or backup destination you’d like them to add to their plugin.

Other features and options to consider in choosing a backup plugin are:

  • Whether encryption of your backup data is available
  • What are the options for automatically deleting backups from the storage destination?
  • Can you globally exclude files, folders, and specific types of files from the backup?
  • Do the options for scheduling automatic backups meet your needs for frequency?
  • Can you exclude/include specific database tables (a good way to save space in your backup)?

WordPress Backup Plugins Review

Let’s review a few of the top choices for WordPress backup plugins.

UpdraftPlus

UpdraftPlus is one of the most popular backup plugins for WordPress with over one million active installations. It is available in both free and Premium versions.

UpdraftPlus just released support for Backblaze B2 Cloud Storage in their 1.13.9 update on September 25. According to the developer, support for Backblaze B2 was the most frequent request for a new storage option for their plugin. B2 support is available in their Premium plugin and as a stand-alone update to their standard product.

Note: The developers of UpdraftPlus are offering a special 20% discount to Backblaze customers on the purchase of UpdraftPlus Premium by using the coupon code backblaze20. The discount is valid until the end of Friday, October 6th, 2017.

screenshot of Backblaze B2 cloud backup for WordPress in UpdraftPlus

XCloner — Backup and Restore

XCloner — Backup and Restore is a useful open-source plugin with many options for backing up WordPress.

XCloner supports B2 Cloud Storage in their free plugin.

screenshot of XCloner WordPress Backblaze B2 backup settings

BlogVault

BlogVault describes themselves as a “complete WordPress backup solution.” They offer a free trial of their paid WordPress backup subscription service that features real-time backups of changes to your WordPress site, as well as many other features.

BlogVault has announced their intent to support Backblaze B2 Cloud Storage in a future update.

screenshot of BlogValut WordPress Backup settings

BackWPup

BackWPup is a popular and free option for backing up WordPress. It supports a number of options for storing your backup, including the cloud, FTP, email, or on your local computer.

screenshot of BackWPup WordPress backup settings

WPBackItUp

WPBackItUp has been around since 2012 and is highly rated. It has both free and paid versions.

screenshot of WPBackItUp WordPress backup settings

VaultPress

VaultPress is part of Automattic’s well-known WordPress product, JetPack. You will need a JetPack subscription plan to use VaultPress. There are different pricing plans with different sets of features.

screenshot of VaultPress backup settings

Backup by Supsystic

Backup by Supsystic supports a number of options for backup destinations, encryption, and scheduling.

screenshot of Backup by Supsystic backup settings

BackupWordPress

BackUpWordPress is an open-source project on Github that has a popular and active following and many positive reviews.

screenshot of BackupWordPress WordPress backup settings

BackupBuddy

BackupBuddy, from iThemes, is the old-timer of backup plugins, having been around since 2010. iThemes knows a lot about WordPress, as they develop plugins, themes, utilities, and provide training in WordPress.

BackupBuddy’s backup includes all WordPress files, all files in the WordPress Media library, WordPress themes, and plugins. BackupBuddy generates a downloadable zip file of the entire WordPress website. Remote storage destinations also are supported.

screenshot of BackupBuddy settings

WordPress and the Cloud

Do you use WordPress and back up to the cloud? We’d like to hear about it. We’d also like to hear whether you are interested in using B2 Cloud Storage for storing media files served by WordPress. If you are, we’ll write about it in a future post.

In the meantime, keep your eye out for new plugins supporting Backblaze B2, or better yet, urge them to support B2 if they’re not already.

The Best Backup Strategy is the One You Use

There are other approaches and tools for backing up WordPress that you might use. If you have an approach that works for you, we’d love to hear about it in the comments.

The post Backing Up WordPress appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

Firefox takes a Quantum leap forward with new developer edition (ars technica)

Post Syndicated from ris original https://lwn.net/Articles/734831/rss

Ars technica takes
a look
at the Firefox 57 developer edition. “More important, but less immediately visible, is that Firefox 57 has received a ton of performance enhancement. Project Quantum has several strands to it: Mozilla has developed a new CSS engine, Stylo, that parses CSS files, applies the styling rules to elements on the page, and calculates object sizes and positions. There is also a new rendering engine, WebRender, that uses the GPU to draw the (styled) elements of the page. Compositor combines the individual rendered elements and builds them into a complete page, while Quantum DOM changes how JavaScript runs, especially in background tabs. As well as this new development, there’s a final part, Quantum Flow, which has focused on fixing bugs and adding optimizations to those parts of the browser that aren’t being redeveloped.

WebRender is due to arrive in Firefox 59, but the rest of Quantum is part of Firefox 57.”

Cryptocurrency Miner Targeted by Anti-Virus and Adblock Tools

Post Syndicated from Ernesto original https://torrentfreak.com/cryptocurrency-miner-targeted-by-anti-virus-and-adblock-tools-170926/

Earlier this month The Pirate Bay caused some uproar by adding a Javascript-based cryptocurrency miner to its website.

The miner utilizes CPU power from visitors to generate Monero coins for the site, providing an extra revenue source.

While Pirate Bay only tested the option briefly, it inspired many others to follow suit. Streaming related sites such as Alluc, Vidoza, and Rapidvideo jumped on board, and torrent site Demonoid also ran some tests.

During the weekend, Coinhive’s miner code even appeared on the official website of Showtime. The code was quickly removed and it’s still unclear how it got there, as the company refuses to comment. It’s clear, though, that miners are a hot topic thanks to The Pirate Bay.

The revenue potential is also real. TorrentFreak spoke to Vidoza who say that with 30,000 online users throughout the day (2M unique visitors), they can make between $500 and $600. That’s when the miner is throttled at 50%. Although ads can bring in more, it’s not insignificant.

That said, all the uproar about cryptocurrency miners and their possible abuse has also attracted the attention of ad-blockers. Some people have coded new browser add-ons to block miners specifically and the popular uBlock Origin added Coinhive to its default blocklist as well. And that’s just after a few days.

Needless to say, this limits the number of miners, and thus the money that comes in. And there’s another problem with a similar effect.

In addition to ad-blockers, anti-virus tools are also flagging Coinhive. Malwarebytes is one of the companies that lists it as a malicious activity, warning users about the threat.

The anti-virus angle is one of the issues that worries Demonoid’s operator. The site is used to ad-blockers, but getting flagged by anti-virus companies is of a different order.

“The problem I see there and the reason we will likely discontinue [use of the miner] is that some anti-virus programs block it, and that might get the site on their blacklists,” Deimos informs TorrentFreak.

Demonoid’s miner announcement

Vidoza operator Eugene sees all the blocking as an unwelcome development and hopes that Coinhive will tackle it. Coinhive may want to come out in public and start to discuss the issue with ad-blockers and anti-virus companies, he says.

“They should find out under what conditions all these guys will stop blocking the script,” he notes.

The other option would be to circumvent the blocking through proxies and circumvention tools, but that might not be the best choice in the long run.

Coinhive, meanwhile, has chimed in as well. The company says that it wasn’t properly prepared for the massive attention and understands why some ad-blockers have put them on the blacklist.

“Providing a real alternative to ads and users who block them turned out to be a much harder problem. Coinhive, too, is now blocked by many ad-block browser extensions, which – we have to admit – is reasonable at this point.”

Most complaints have been targeted at sites that implemented the miner without the user’s consent. Coinhive doesn’t like this either and will take steps to prevent it in future.

“We’re a bit saddened to see that some of our customers integrate Coinhive into their pages without disclosing to their users what’s going on, let alone asking for their permission,” the Coinhive team notes.

The crypto miner provider is working on a new implementation that requires explicit consent from website visitors in order to run. This should deal with most of the negative responses.

If users start mining voluntarily, then ad-blockers and anti-virus companies should no longer have a reason to block the script. Nor will it be easy for malware peddlers to abuse it.

To be continued.

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

Are Cryptocurrency Miners The Future for Pirate Sites?

Post Syndicated from Ernesto original https://torrentfreak.com/are-cryptocurrency-miners-the-future-for-pirate-sites-170921/

Last weekend The Pirate Bay surprised friend and foe by adding a Javascript-based cryptocurrency miner to its website.

The miner utilizes CPU power from visitors to generate Monero coins for the site, providing an extra revenue source.

Initially, this caused the CPUs of visitors to max out due to a configuration error, but it was later adjusted to be less demanding. Still, there was plenty of discussion on the move, with greatly varying opinions.

Some criticized the site for “hijacking” their computer resources for personal profit, without prior warning. However, there are also people who are happy to give something back to TPB, especially if it can help the site to remain online.

Aside from the configuration error, there was another major mistake everyone agreed on. The Pirate Bay team should have alerted its visitors to this change beforehand, and not after the fact, as they did last weekend.

Despite the sensitivities, The Pirate Bay’s move has inspired others to follow suit. Pirate linking site Alluc.ee is one of the first. While they use the same mining service, their implementation is more elegant.

Alluc shows how many hashes are mined and the site allows users to increase or decrease the CPU load, or turn the miner off completely.

Alluc.ee miner

Putting all the controversy aside for a minute, the idea to let visitors mine coins is a pretty ingenious idea. The Pirate Bay said it was testing the feature to see if it’s possible as a replacement for ads, which might be much needed in the future.

In recent years many pirate sites have struggled to make a decent income. Not only are more people using ad-blockers now, the ad-quality is also dropping as copyright holders actively go after this revenue source, trying to dry up the funds of pirate sites. And with Chrome planning to add a default ad-blocker to its browser, the outlook is grim.

A cryptocurrency miner might alleviate this problem. That is, as long as ad-blockers don’t start to interfere with this revenue source as well.

Interestingly, this would also counter one of the main anti-piracy talking points. Increasingly, industry groups are using the “public safety” argument as a reason to go after pirate sites. They point to malicious advertisements as a great danger, hoping that this will further their calls for tougher legislation and enforcement.

If The Pirate Bay and other pirate sites can ditch the ads, they would be less susceptible to these and other anti-piracy pushes. Of course, copyright holders could still go after the miner revenues, but this might not be easy.

TorrentFreak spoke to Coinhive, the company that provides the mining service to The Pirate Bay, and they don’t seem eager to take action without a court order.

“We don’t track where users come from. We are just providing servers and a script to submit hashes for the Monero blockchain. We don’t see it as our responsibility to determine if a website is ‘valid’ and we don’t have the technical capabilities to do so,” a Coinhive representative says.

We also contacted several site owners and thus far the response has been mixed. Some like the idea and would consider adding a miner, if it doesn’t affect visitors too much. Others are more skeptical and don’t believe that the extra revenue is worth the trouble.

The Pirate Bay itself, meanwhile, has completed its test run and has removed the miner from the site. They will now analyze the results before deciding whether or not it’s “the future” for them.

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

SecureLogin For Java Web Applications

Post Syndicated from Bozho original https://techblog.bozho.net/securelogin-java-web-applications/

No, there is not a missing whitespace in the title. It’s not about any secure login, it’s about the SecureLogin protocol developed by Egor Homakov, a security consultant, who became famous for committing to master in the Rails project without having permissions.

The SecureLogin protocol is very interesting, as it does not rely on any central party (e.g. OAuth providers like Facebook and Twitter), thus avoiding all the pitfalls of OAuth (which Homakov has often criticized). It is not a password manager either. It is just a client-side software that performs a bit of crypto in order to prove to the server that it is indeed the right user. For that to work, two parts are key:

  • Using a master password to generate a private key. It uses a key-derivation function, which guarantees that the produced private key has sufficient entropy. That way, using the same master password and the same email, you will get the same private key everytime you use the password, and therefore the same public key. And you are the only one who can prove this public key is yours, by signing a message with your private key.
  • Service providers (websites) identify you by your public key by storing it in the database when you register and then looking it up on each subsequent login

The client-side part is performed ideally by a native client – a browser plugin (one is available for Chrome) or a OS-specific application (including mobile ones). That may sound tedious, but it’s actually quick and easy and a one-time event (and is easier than password managers).

I have to admit – I like it, because I’ve been having a similar idea for a while. In my “biometric identification” presentation (where I discuss the pitfalls of using biometrics-only identification schemes), I proposed (slide 23) an identification scheme that uses biometrics (e.g. scanned with your phone) + a password to produce a private key (using a key-derivation function). And the biometric can easily be added to SecureLogin in the future.

It’s not all roses, of course, as one issue isn’t fully resolved yet – revocation. In case someone steals your master password (or you suspect it might be stolen), you may want to change it and notify all service providers of that change so that they can replace your old public key with a new one. That has two implications – first, you may not have a full list of sites that you registered on, and since you may have changed devices, or used multiple devices, there may be websites that never get to know about your password change. There are proposed solutions (points 3 and 4), but they are not intrinsic to the protocol and rely on centralized services. The second issue is – what if the attacker changes your password first? To prevent that, service providers should probably rely on email verification, which is neither part of the protocol, nor is encouraged by it. But you may have to do it anyway, as a safeguard.

Homakov has not only defined a protocol, but also provided implementations of the native clients, so that anyone can start using it. So I decided to add it to a project I’m currently working on (the login page is here). For that I needed a java implementation of the server verification, and since no such implementation existed (only ruby and node.js are provided for now), I implemented it myself. So if you are going to use SecureLogin with a Java web application, you can use that instead of rolling out your own. While implementing it, I hit a few minor issues that may lead to protocol changes, so I guess backward compatibility should also be somehow included in the protocol (through versioning).

So, how does the code look like? On the client side you have a button and a little javascript:

<!-- get the latest sdk.js from the GitHub repo of securelogin
   or include it from https://securelogin.pw/sdk.js -->
<script src="js/securelogin/sdk.js"></script>
....
<p class="slbutton" id="securelogin">&#9889; SecureLogin</p>
$("#securelogin").click(function() {
  SecureLogin(function(sltoken){
	// TODO: consider adding csrf protection as in the demo applications
        // Note - pass as request body, not as param, as the token relies 
        // on url-encoding which some frameworks mess with
	$.post('/app/user/securelogin', sltoken, function(result) {
            if(result == 'ok') {
		 window.location = "/app/";
            } else {
                 $.notify("Login failed, try again later", "error");
            }
	});
  });
  return false;
});

A single button can be used for both login and signup, or you can have a separate signup form, if it has to include additional details rather than just an email. Since I added SecureLogin in addition to my password-based login, I kept the two forms.

On the server, you simply do the following:

@RequestMapping(value = "/securelogin/register", method = RequestMethod.POST)
@ResponseBody
public String secureloginRegister(@RequestBody String token, HttpServletResponse response) {
    try {
        SecureLogin login = SecureLogin.verify(request.getSecureLoginToken(), Options.create(websiteRootUrl));
        UserDetails details = userService.getUserDetailsByEmail(login.getEmail());
        if (details == null || !login.getRawPublicKey().equals(details.getSecureLoginPublicKey())) {
            return "failure";
        }
        // sets the proper cookies to the response
        TokenAuthenticationService.addAuthentication(response, login.getEmail(), secure));
        return "ok";
    } catch (SecureLoginVerificationException e) {
        return "failure";
    }
}

This is spring-mvc, but it can be any web framework. You can also incorporate that into a spring-security flow somehow. I’ve never liked spring-security’s complexity, so I did it manually. Also, instead of strings, you can return proper status codes. Note that I’m doing a lookup by email and only then checking the public key (as if it’s a password). You can do the other way around if you have the proper index on the public key column.

I wouldn’t suggest having a SecureLogin-only system, as the project is still in an early stage and users may not be comfortable with it. But certainly adding it as an option is a good idea.

The post SecureLogin For Java Web Applications appeared first on Bozho's tech blog.

The Pirate Bay Website Runs a Cryptocurrency Miner

Post Syndicated from Ernesto original https://torrentfreak.com/the-pirate-bay-website-runs-a-cryptocurrency-miner-170916/

Four years ago many popular torrent sites added an option to donate via Bitcoin. The Pirate Bay was one of the first to jump on board and still lists its address on the website.

While there’s nothing wrong with using Bitcoin as a donation tool, adding a Javascript cryptocurrency miner to a site is of a totally different order.

A few hours ago many Pirate Bay users began noticing that their CPU usage increased dramatically when they browsed certain Pirate Bay pages. Upon closer inspection, this spike appears to have been caused by a Bitcoin miner embedded on the site.

The code in question is tucked away in the site’s footer and uses a miner provided by Coinhive. This service offers site owners the option to convert the CPU power of users into Monero coins.

The miner does indeed appear to increase CPU usage quite a bit. It is throttled at different rates (we’ve seen both 0.6 and 0.8) but the increase in resources is immediately noticeable.

The miner is not enabled site-wide. When we checked, it appeared in the search results and category listings, but not on the homepage or individual torrent pages.

There has been no official comment from the site operators on the issue (update, see below), but many users have complained about it. In the official site forums, TPB supermoderator Sid is clearly not in agreement with the site’s latest addition.

“That really is serious, so hopefully we can get some action on it quickly. And perhaps get some attention for the uploading and commenting bugs while they’re at it,” Sid writes.

Like many others, he also points out that blocking or disabling Javascript can stop the automatic mining. This can be done via browser settings or through script blocker addons such as NoScript and ScriptBlock. Alternatively, people can block the miner URL with an ad-blocker.

Whether the miner is a new and permanent tool, or perhaps triggered by an advertiser, is unknown at the point. When we hear more this article will be updated accordingly.

Update: We were told that the miner is being tested for a short period as a new way to generate revenue. This could eventually replace the ads on the site. More info may be revealed later.

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

[$] Mongoose OS for IoT prototyping

Post Syndicated from jake original https://lwn.net/Articles/733297/rss

Mongoose OS is an open-source
operating system for tiny embedded systems. It is designed to run on
devices such as microcontrollers, which are often constrained with memory on the
order of tens of kilobytes, while exposing a programming interface that
provides access to modern APIs normally found on more powerful devices. A
device running Mongoose OS has access to operating system functionality
such as filesystems and networking, plus higher-level software such as a
JavaScript engine and cloud access APIs.

Make your own game with CoderDojo’s new book

Post Syndicated from Nuala McHale original https://www.raspberrypi.org/blog/coderdojo-nano/

The first official CoderDojo book, CoderDojo Nano: Build Your Own Website, was a resounding success: thousands of copies have been bought by aspiring CoderDojo Ninjas, and it‘s available in ten languages, including Bulgarian, Czech, Dutch, Lithuanian, Latvian, Portuguese, Spanish, and Slovakian. Now we are delighted to announce the release of the second book in our Create with Code trilogy, titled CoderDojo Nano: Make Your Own Game.

Cover of CoderDojo Nano Make your own game

The paperback book will be available in English from Thursday 7 September (with English flexibound and Dutch versions scheduled to follow in the coming months), enabling young people and adults to learn creative and fun coding skills!

What will you learn?

The new book explains the fundamentals of the JavaScript language in a clear, logical way while supporting you to create your very own computer game.

Pixel image of laptop displaying a jump-and-run game

You will learn how to animate characters, create a world for your game, and use the physics of movement within it. The book is full of clear step-by-step instructions and illustrated screenshots to make reviewing your code easy. Additionally, challenges and open-ended prompts at the end of each section will encourage you to get creative while making your game.

This book is the perfect first step towards understanding game development, particularly for those of you who do not (yet) have a local Dojo. Regardless of where you live, using our books you too can learn to ‘Create with Code’!

Tried and tested

As always, CoderDojo Ninjas from all around the world tested our book, and their reactions have been hugely positive. Here is a selection of their thoughts:

“The book is brilliant. The [game] is simple yet innovative. I personally love it, and want to get stuck in making it right away!”

“What I really like is that, unlike most books on coding, this one properly explains what’s happening, and what each piece of code does and where it comes from.”

“I found the book most enjoyable. The layout is great, with lots of colour, and I found the information very easy to follow. The Ninja Tips are a great help in case you get a bit stuck. I liked that the book represents a mix of boy and girl Ninjas — it really makes coding fun for all.”

“The book is a great guide for both beginners and people who want to do something creative with their knowledge of code. Even people who cannot go to a CoderDojo can learn code using this book!”

Writer Jurie Horneman

Author of CoderDojo Nano: Make Your Own Game Jurie Horneman has been working in the game development industry for more than 15 years.

stuffed toy rabbit wearing glasses

Jurie would get on well with Babbage, I think.

He shares how he got into coding, and what he has learnt while creating this awesome book:

“I’ve been designing and programming games since 1991, starting with ancient home computers, and now I’m working with PCs and consoles. As a game designer, it’s my job to teach players the rules of the game in a fun and playful manner — that gave me some useful experience for writing the book.

I believe that, if you want to understand something properly, you have to teach it to others. Therefore, writing this book was very educational for me, as I hope reading it will be for learners.”

Asked what his favorite thing about the book is, Jurie said he loves the incredible pixel art design: “The artist (Gary J Lucken, Army of Trolls) did a great job to help explain some of the abstract concepts in the book.”

Pixel image of a landscape with an East Asian temple on a lonely mountain

Gary’s art is also just gorgeous.

How can you get your copy?

You can pre-order CoderDojo Nano: Make Your Own Game here. Its initial pricing is £9.99 (around €11), and discounted copies with free international delivery are available here.

The post Make your own game with CoderDojo’s new book appeared first on Raspberry Pi.

Five Must-Watch Software Engineering Talks

Post Syndicated from Bozho original https://techblog.bozho.net/five-must-watch-software-engineering-talks/

We’ve all watched dozens of talks online. And we probably don’t remember many of them. But some do stick in our heads and we eventually watch them again (and again) because we know they are good and we want to remember the things that were said there. So I decided to compile a small list of talks that I find very insightful, useful and that have, in a way, shaped my software engineering practice or expanded my understanding of the software world.

1. How To Design A Good API and Why it Matters by Joshua Bloch – this is a must-watch (well, obviously all are). And don’t skip it because “you are not writing APIs” – everyone is writing APIs. Maybe not used by hundreds of other developers, but used by at least several, and that’s a good enough reason. Having watched this talk I ended up buying and reading one of the few software books that I have actually read end-to-end – “Effective Java” (the talk uses Java as an example, but the principles aren’t limited to Java)

2. How to write clean, testable code by Miško Hevery. Maybe there are tons of talks about testing code, maybe Uncle Bob has a more popular one, but I found this one particularly practical and the the point – that writing testable code is a skill, and that testable code is good code. (By the way, the speaker then wrote AngularJS)

3. Back to basics: the mess we’ve made of our fundamental data types by Jon Skeet. The title says it all, and it’s nice to be reminded of how fragile even the basics of programming languages are.

4. The Danger of Software Patents by Richard Stallman. That goes a little bit away from writing software, but puts software in legal context – how do legislation loopholes affect code reuse and business practices related it. It’s a bit long, but I think worth it.

5. Does my ESB look big in this? by Martin Fowler and Jim Webber. It’s about bloated enterprise architecture and how to actually do enterprise architecture without complex and expensive middleware. (Unfortunately it’s not on YouTube, so no embedding).

Although this is not a “ranking”, I’d like to add a few honourable mentions: The famous “WAT” lightning talk, showing some quirks of ruby and javascript, “The future of programming” by Bret Victor, “You suck at Excel” by Joel Spolsky, which isn’t really about creating software, but it’s cool. And a tiny shameless plug with my “Common sense driven development talk”

I hope the compilation is useful and enlightening. Enjoy.

The post Five Must-Watch Software Engineering Talks appeared first on Bozho's tech blog.

How Aussie ecommerce stores can compete with the retail giant Amazon

Post Syndicated from chris desantis original https://www.anchor.com.au/blog/2017/08/aussie-ecommerce-stores-vs-amazon/

The powerhouse Amazon retail store is set to launch in Australia toward the end of 2018 and Aussie ecommerce retailers need to ready themselves for the competition storm ahead.

2018 may seem a while away but getting your ecommerce site in tip top shape and ready to compete can take time. Check out these helpful hints from the Anchor crew.

Speed kills

If you’ve ever heard of the tale of the tortoise and the hare, the moral is that “slow and steady wins the race”. This is definitely not the place for that phrase, because if your site loads as slowly as a 1995 dial up connection, your ecommerce store will not, I repeat, will not win the race.

Site speed can be impacted by a number of factors and getting the balance right between a site that loads at lightning speed and delivering engaging content to your audience. There are many ways to check the performance of your site including Anchor’s free hosting check up or pingdom.

Taking action can boost the performance of your site:

Here’s an interesting blog from the WebCEO team about site speed’s impact on conversion rates on-page, or check out our previous blog on maximising site performance.

Show me the money

As an ecommerce store, getting credit card details as fast as possible is probably at the top of your list, but it’s important to remember that it’s an actual person that needs to hand over the details.

Consider the customer’s experience whilst checking out. Making people log in to their account before checkout, can lead to abandoned carts as customers try to remember the vital details. Similarly, making a customer enter all their details before displaying shipping costs is more of an annoyance than a benefit.

Built for growth

Before you blast out a promo email to your entire database or spend up big on PPC, consider what happens when this 5 fold increase in traffic, all jumps onto your site at around the same time.

Will your site come screeching to a sudden halt with a 504 or 408 error message, or ride high on the wave of increased traffic? If you have fixed infrastructure such as a dedicated server, or are utilising a VPS, then consider the maximum concurrent users that your site can handle.

Consider this. Amazon.com.au will be built on the scalable cloud infrastructure of Amazon Web Services and will utilise all the microservices and data mining technology to offer customers a seamless, personalised shopping experience. How will your business compete?

Search ready

Being found online is important for any business, but for ecommerce sites, it’s essential. Gaining results from SEO practices can take time so beware of ‘quick fix guarantees’ from outsourced agencies.

Search Engine Optimisation (SEO) practices can have lasting effects. Good practices can ensure your site is found via organic search without huge advertising budgets, on the other hand ‘black hat’ practices can push your ecommerce store into search oblivion.

SEO takes discipline and focus to get right. Here are some of our favourite hints for SEO greatness from those who live and breathe SEO:

  • Optimise your site for mobile
  • Use Meta Tags wisely
  • Leverage Descriptive alt tags and image file names
  • Create content for people, not bots (keyword stuffing is a no no!)

SEO best practices are continually evolving, but creating a site that is designed to give users a great experience and give them the content they expect to find.

Google My Business is a free service that EVERY business should take advantage of. It is a listing service where your business can provide details such as address, phone number, website, and trading hours. It’s easy to update and manage, you can add photos, a physical address (if applicable), and display shopper reviews.

Get your site ship shape

Overwhelmed by these starter tips? If you are ready to get your site into tip top shape–get in touch. We work with awesome partners like eWave who can help create a seamless online shopping experience.

 

The post How Aussie ecommerce stores can compete with the retail giant Amazon appeared first on AWS Managed Services by Anchor.

Announcing the Winners of the AWS Chatbot Challenge – Conversational, Intelligent Chatbots using Amazon Lex and AWS Lambda

Post Syndicated from Tara Walker original https://aws.amazon.com/blogs/aws/announcing-the-winners-of-the-aws-chatbot-challenge-conversational-intelligent-chatbots-using-amazon-lex-and-aws-lambda/

A couple of months ago on the blog, I announced the AWS Chatbot Challenge in conjunction with Slack. The AWS Chatbot Challenge was an opportunity to build a unique chatbot that helped to solve a problem or that would add value for its prospective users. The mission was to build a conversational, natural language chatbot using Amazon Lex and leverage Lex’s integration with AWS Lambda to execute logic or data processing on the backend.

I know that you all have been anxiously waiting to hear announcements of who were the winners of the AWS Chatbot Challenge as much as I was. Well wait no longer, the winners of the AWS Chatbot Challenge have been decided.

May I have the Envelope Please? (The Trumpets sound)

The winners of the AWS Chatbot Challenge are:

  • First Place: BuildFax Counts by Joe Emison
  • Second Place: Hubsy by Andrew Riess, Andrew Puch, and John Wetzel
  • Third Place: PFMBot by Benny Leong and his team from MoneyLion.
  • Large Organization Winner: ADP Payroll Innovation Bot by Eric Liu, Jiaxing Yan, and Fan Yang

 

Diving into the Winning Chatbot Projects

Let’s take a walkthrough of the details for each of the winning projects to get a view of what made these chatbots distinctive, as well as, learn more about the technologies used to implement the chatbot solution.

 

BuildFax Counts by Joe Emison

The BuildFax Counts bot was created as a real solution for the BuildFax company to decrease the amount the time that sales and marketing teams can get answers on permits or properties with permits meet certain criteria.

BuildFax, a company co-founded by bot developer Joe Emison, has the only national database of building permits, which updates data from approximately half of the United States on a monthly basis. In order to accommodate the many requests that come in from the sales and marketing team regarding permit information, BuildFax has a technical sales support team that fulfills these requests sent to a ticketing system by manually writing SQL queries that run across the shards of the BuildFax databases. Since there are a large number of requests received by the internal sales support team and due to the manual nature of setting up the queries, it may take several days for getting the sales and marketing teams to receive an answer.

The BuildFax Counts chatbot solves this problem by taking the permit inquiry that would normally be sent into a ticket from the sales and marketing team, as input from Slack to the chatbot. Once the inquiry is submitted into Slack, a query executes and the inquiry results are returned immediately.

Joe built this solution by first creating a nightly export of the data in their BuildFax MySQL RDS database to CSV files that are stored in Amazon S3. From the exported CSV files, an Amazon Athena table was created in order to run quick and efficient queries on the data. He then used Amazon Lex to create a bot to handle the common questions and criteria that may be asked by the sales and marketing teams when seeking data from the BuildFax database by modeling the language used from the BuildFax ticketing system. He added several different sample utterances and slot types; both custom and Lex provided, in order to correctly parse every question and criteria combination that could be received from an inquiry.  Using Lambda, Joe created a Javascript Lambda function that receives information from the Lex intent and used it to build a SQL statement that runs against the aforementioned Athena database using the AWS SDK for JavaScript in Node.js library to return inquiry count result and SQL statement used.

The BuildFax Counts bot is used today for the BuildFax sales and marketing team to get back data on inquiries immediately that previously took up to a week to receive results.

Not only is BuildFax Counts bot our 1st place winner and wonderful solution, but its creator, Joe Emison, is a great guy.  Joe has opted to donate his prize; the $5,000 cash, the $2,500 in AWS Credits, and one re:Invent ticket to the Black Girls Code organization. I must say, you rock Joe for helping these kids get access and exposure to technology.

 

Hubsy by Andrew Riess, Andrew Puch, and John Wetzel

Hubsy bot was created to redefine and personalize the way users traditionally manage their HubSpot account. HubSpot is a SaaS system providing marketing, sales, and CRM software. Hubsy allows users of HubSpot to create engagements and log engagements with customers, provide sales teams with deals status, and retrieves client contact information quickly. Hubsy uses Amazon Lex’s conversational interface to execute commands from the HubSpot API so that users can gain insights, store and retrieve data, and manage tasks directly from Facebook, Slack, or Alexa.

In order to implement the Hubsy chatbot, Andrew and the team members used AWS Lambda to create a Lambda function with Node.js to parse the users request and call the HubSpot API, which will fulfill the initial request or return back to the user asking for more information. Terraform was used to automatically setup and update Lambda, CloudWatch logs, as well as, IAM profiles. Amazon Lex was used to build the conversational piece of the bot, which creates the utterances that a person on a sales team would likely say when seeking information from HubSpot. To integrate with Alexa, the Amazon Alexa skill builder was used to create an Alexa skill which was tested on an Echo Dot. Cloudwatch Logs are used to log the Lambda function information to CloudWatch in order to debug different parts of the Lex intents. In order to validate the code before the Terraform deployment, ESLint was additionally used to ensure the code was linted and proper development standards were followed.

 

PFMBot by Benny Leong and his team from MoneyLion

PFMBot, Personal Finance Management Bot,  is a bot to be used with the MoneyLion finance group which offers customers online financial products; loans, credit monitoring, and free credit score service to improve the financial health of their customers. Once a user signs up an account on the MoneyLion app or website, the user has the option to link their bank accounts with the MoneyLion APIs. Once the bank account is linked to the APIs, the user will be able to login to their MoneyLion account and start having a conversation with the PFMBot based on their bank account information.

The PFMBot UI has a web interface built with using Javascript integration. The chatbot was created using Amazon Lex to build utterances based on the possible inquiries about the user’s MoneyLion bank account. PFMBot uses the Lex built-in AMAZON slots and parsed and converted the values from the built-in slots to pass to AWS Lambda. The AWS Lambda functions interacting with Amazon Lex are Java-based Lambda functions which call the MoneyLion Java-based internal APIs running on Spring Boot. These APIs obtain account data and related bank account information from the MoneyLion MySQL Database.

 

ADP Payroll Innovation Bot by Eric Liu, Jiaxing Yan, and Fan Yang

ADP PI (Payroll Innovation) bot is designed to help employees of ADP customers easily review their own payroll details and compare different payroll data by just asking the bot for results. The ADP PI Bot additionally offers issue reporting functionality for employees to report payroll issues and aids HR managers in quickly receiving and organizing any reported payroll issues.

The ADP Payroll Innovation bot is an ecosystem for the ADP payroll consisting of two chatbots, which includes ADP PI Bot for external clients (employees and HR managers), and ADP PI DevOps Bot for internal ADP DevOps team.


The architecture for the ADP PI DevOps bot is different architecture from the ADP PI bot shown above as it is deployed internally to ADP. The ADP PI DevOps bot allows input from both Slack and Alexa. When input comes into Slack, Slack sends the request to Lex for it to process the utterance. Lex then calls the Lambda backend, which obtains ADP data sitting in the ADP VPC running within an Amazon VPC. When input comes in from Alexa, a Lambda function is called that also obtains data from the ADP VPC running on AWS.

The architecture for the ADP PI bot consists of users entering in requests and/or entering issues via Slack. When requests/issues are entered via Slack, the Slack APIs communicate via Amazon API Gateway to AWS Lambda. The Lambda function either writes data into one of the Amazon DynamoDB databases for recording issues and/or sending issues or it sends the request to Lex. When sending issues, DynamoDB integrates with Trello to keep HR Managers abreast of the escalated issues. Once the request data is sent from Lambda to Lex, Lex processes the utterance and calls another Lambda function that integrates with the ADP API and it calls ADP data from within the ADP VPC, which runs on Amazon Virtual Private Cloud (VPC).

Python and Node.js were the chosen languages for the development of the bots.

The ADP PI bot ecosystem has the following functional groupings:

Employee Functionality

  • Summarize Payrolls
  • Compare Payrolls
  • Escalate Issues
  • Evolve PI Bot

HR Manager Functionality

  • Bot Management
  • Audit and Feedback

DevOps Functionality

  • Reduce call volume in service centers (ADP PI Bot).
  • Track issues and generate reports (ADP PI Bot).
  • Monitor jobs for various environment (ADP PI DevOps Bot)
  • View job dashboards (ADP PI DevOps Bot)
  • Query job details (ADP PI DevOps Bot)

 

Summary

Let’s all wish all the winners of the AWS Chatbot Challenge hearty congratulations on their excellent projects.

You can review more details on the winning projects, as well as, all of the submissions to the AWS Chatbot Challenge at: https://awschatbot2017.devpost.com/submissions. If you are curious on the details of Chatbot challenge contest including resources, rules, prizes, and judges, you can review the original challenge website here:  https://awschatbot2017.devpost.com/.

Hopefully, you are just as inspired as I am to build your own chatbot using Lex and Lambda. For more information, take a look at the Amazon Lex developer guide or the AWS AI blog on Building Better Bots Using Amazon Lex (Part 1)

Chat with you soon!

Tara

What’s the Diff: Programs, Processes, and Threads

Post Syndicated from Roderick Bauer original https://www.backblaze.com/blog/whats-the-diff-programs-processes-and-threads/

let's talk about Threads

How often have you heard the term threading in relation to a computer program, but you weren’t exactly sure what it meant? How about processes? You likely understand that a thread is somehow closely related to a program and a process, but if you’re not a computer science major, maybe that’s as far as your understanding goes.

Knowing what these terms mean is absolutely essential if you are a programmer, but an understanding of them also can be useful to the average computer user. Being able to look at and understand the Activity Monitor on the Macintosh, the Task Manager on Windows, or Top on Linux can help you troubleshoot which programs are causing problems on your computer, or whether you might need to install more memory to make your system run better.

Let’s take a few minutes to delve into the world of computer programs and sort out what these terms mean. We’ll simplify and generalize some of the ideas, but the general concepts we cover should help clarify the difference between the terms.

Programs

First of all, you probably are aware that a program is the code that is stored on your computer that is intended to fulfill a certain task. There are many types of programs, including programs that help your computer function and are part of the operating system, and other programs that fulfill a particular job. These task-specific programs are also known as “applications,” and can include programs such as word processing, web browsing, or emailing a message to another computer.

Program

Programs are typically stored on disk or in non-volatile memory in a form that can be executed by your computer. Prior to that, they are created using a programming language such as C, Lisp, Pascal, or many others using instructions that involve logic, data and device manipulation, recurrence, and user interaction. The end result is a text file of code that is compiled into binary form (1’s and 0’s) in order to run on the computer. Another type of program is called “interpreted,” and instead of being compiled in advance in order to run, is interpreted into executable code at the time it is run. Some common, typically interpreted programming languages, are Python, PHP, JavaScript, and Ruby.

The end result is the same, however, in that when a program is run, it is loaded into memory in binary form. The computer’s CPU (Central Processing Unit) understands only binary instructions, so that’s the form the program needs to be in when it runs.

Perhaps you’ve heard the programmer’s joke, “There are only 10 types of people in the world, those who understand binary, and those who don’t.”

Binary is the native language of computers because an electrical circuit at its basic level has two states, on or off, represented by a one or a zero. In the common numbering system we use every day, base 10, each digit position can be anything from 0 to 9. In base 2 (or binary), each position is either a 0 or a 1. (In a future blog post we might cover quantum computing, which goes beyond the concept of just 1’s and 0’s in computing.)

Decimal—Base 10 Binary—Base 2
0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000
9 1001

How Processes Work

The program has been loaded into the computer’s memory in binary form. Now what?

An executing program needs more than just the binary code that tells the computer what to do. The program needs memory and various operating system resources that it needs in order to run. A “process” is what we call a program that has been loaded into memory along with all the resources it needs to operate. The “operating system” is the brains behind allocating all these resources, and comes in different flavors such as macOS, iOS, Microsoft Windows, Linux, and Android. The OS handles the task of managing the resources needed to turn your program into a running process.

Some essential resources every process needs are registers, a program counter, and a stack. The “registers” are data holding places that are part of the computer processor (CPU). A register may hold an instruction, a storage address, or other kind of data needed by the process. The “program counter,” also called the “instruction pointer,” keeps track of where a computer is in its program sequence. The “stack” is a data structure that stores information about the active subroutines of a computer program and is used as scratch space for the process. It is distinguished from dynamically allocated memory for the process that is known as “the heap.”

diagram of how processes work

There can be multiple instances of a single program, and each instance of that running program is a process. Each process has a separate memory address space, which means that a process runs independently and is isolated from other processes. It cannot directly access shared data in other processes. Switching from one process to another requires some time (relatively) for saving and loading registers, memory maps, and other resources.

This independence of processes is valuable because the operating system tries its best to isolate processes so that a problem with one process doesn’t corrupt or cause havoc with another process. You’ve undoubtedly run into the situation in which one application on your computer freezes or has a problem and you’ve been able to quit that program without affecting others.

How Threads Work

So, are you still with us? We finally made it to threads!

A thread is the unit of execution within a process. A process can have anywhere from just one thread to many threads.

Process vs. Thread

diagram of threads in a process over time

When a process starts, it is assigned memory and resources. Each thread in the process shares that memory and resources. In single-threaded processes, the process contains one thread. The process and the thread are one and the same, and there is only one thing happening.

In multithreaded processes, the process contains more than one thread, and the process is accomplishing a number of things at the same time (technically, it’s almost at the same time—read more on that in the “What about Parallelism and Concurrency?” section below).

diagram of single and multi-treaded process

We talked about the two types of memory available to a process or a thread, the stack and the heap. It is important to distinguish between these two types of process memory because each thread will have its own stack, but all the threads in a process will share the heap.

Threads are sometimes called lightweight processes because they have their own stack but can access shared data. Because threads share the same address space as the process and other threads within the process, the operational cost of communication between the threads is low, which is an advantage. The disadvantage is that a problem with one thread in a process will certainly affect other threads and the viability of the process itself.

Threads vs. Processes

So to review:

  1. The program starts out as a text file of programming code,
  2. The program is compiled or interpreted into binary form,
  3. The program is loaded into memory,
  4. The program becomes one or more running processes.
  5. Processes are typically independent of each other,
  6. While threads exist as the subset of a process.
  7. Threads can communicate with each other more easily than processes can,
  8. But threads are more vulnerable to problems caused by other threads in the same process.

Processes vs. Threads — Advantages and Disadvantages

Process Thread
Processes are heavyweight operations Threads are lighter weight operations
Each process has its own memory space Threads use the memory of the process they belong to
Inter-process communication is slow as processes have different memory addresses Inter-thread communication can be faster than inter-process communication because threads of the same process share memory with the process they belong to
Context switching between processes is more expensive Context switching between threads of the same process is less expensive
Processes don’t share memory with other processes Threads share memory with other threads of the same process

What about Concurrency and Parallelism?

A question you might ask is whether processes or threads can run at the same time. The answer is: it depends. On a system with multiple processors or CPU cores (as is common with modern processors), multiple processes or threads can be executed in parallel. On a single processor, though, it is not possible to have processes or threads truly executing at the same time. In this case, the CPU is shared among running processes or threads using a process scheduling algorithm that divides the CPU’s time and yields the illusion of parallel execution. The time given to each task is called a “time slice.” The switching back and forth between tasks happens so fast it is usually not perceptible. The terms parallelism (true operation at the same time) and concurrency (simulated operation at the same time), distinguish between the two type of real or approximate simultaneous operation.

diagram of concurrency and parallelism

Why Choose Process over Thread, or Thread over Process?

So, how would a programmer choose between a process and a thread when creating a program in which she wants to execute multiple tasks at the same time? We’ve covered some of the differences above, but let’s look at a real world example with a program that many of us use, Google Chrome.

When Google was designing the Chrome browser, they needed to decide how to handle the many different tasks that needed computer, communications, and network resources at the same time. Each browser window or tab communicates with multiple servers on the internet to retrieve text, programs, graphics, audio, video, and other resources, and renders that data for display and interaction with the user. In addition, the browser can open many windows, each with many tasks.

Google had to decide how to handle that separation of tasks. They chose to run each browser window in Chrome as a separate process rather than a thread or many threads, as is common with other browsers. Doing that brought Google a number of benefits. Running each window as a process protects the overall application from bugs and glitches in the rendering engine and restricts access from each rendering engine process to others and to the rest of the system. Isolating JavaScript programs in a process prevents them from running away with too much CPU time and memory, and making the entire browser non-responsive.

Google made the calculated trade-off with a multi-processing design as starting a new process for each browser window has a higher fixed cost in memory and resources than using threads. They were betting that their approach would end up with less memory bloat overall.

Using processes instead of threads provides better memory usage when memory gets low. An inactive window is treated as a lower priority by the operating system and becomes eligible to be swapped to disk when memory is needed for other processes, helping to keep the user-visible windows more responsive. If the windows were threaded, it would be more difficult to separate the used and unused memory as cleanly, wasting both memory and performance.

You can read more about Google’s design decisions on Google’s Chromium Blog or on the Chrome Introduction Comic.

The screen capture below shows the Google Chrome processes running on a MacBook Air with many tabs open. Some Chrome processes are using a fair amount of CPU time and resources, and some are using very little. You can see that each process also has many threads running as well.

activity monitor of Google Chrome

The Activity Monitor or Task Manager on your system can be a valuable ally in helping fine-tune your computer or troubleshooting problems. If your computer is running slowly, or a program or browser window isn’t responding for a while, you can check its status using the system monitor. Sometimes you’ll see a process marked as “Not Responding.” Try quitting that process and see if your system runs better. If an application is a memory hog, you might consider choosing a different application that will accomplish the same task.

Windows Task Manager view

Made it This Far?

We hope this Tron-like dive into the fascinating world of computer programs, processes, and threads has helped clear up some questions you might have had.

The next time your computer is running slowly or an application is acting up, you know your assignment. Fire up the system monitor and take a look under the hood to see what’s going on. You’re in charge now.

We love to hear from you

Are you still confused? Have questions? If so, please let us know in the comments. And feel free to suggest topics for future blog posts.

The post What’s the Diff: Programs, Processes, and Threads appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

Wanted: Front End Developer

Post Syndicated from Yev original https://www.backblaze.com/blog/wanted-front-end-developer/

Want to work at a company that helps customers in over 150 countries around the world protect the memories they hold dear? Do you want to challenge yourself with a business that serves consumers, SMBs, Enterprise, and developers? If all that sounds interesting, you might be interested to know that Backblaze is looking for a Front End Developer​!

Backblaze is a 10 year old company. Providing great customer experiences is the “secret sauce” that enables us to successfully compete against some of technology’s giants. We’ll finish the year at ~$20MM ARR and are a profitable business. This is an opportunity to have your work shine at scale in one of the fastest growing verticals in tech – Cloud Storage.

You will utilize HTML, ReactJS, CSS and jQuery to develop intuitive, elegant user experiences. As a member of our Front End Dev team, you will work closely with our web development, software design, and marketing teams.

On a day to day basis, you must be able to convert image mockups to HTML or ReactJS – There’s some production work that needs to get done. But you will also be responsible for helping build out new features, rethink old processes, and enabling third party systems to empower our marketing/sales/ and support teams.

Our Front End Developer must be proficient in:

  • HTML, ReactJS
  • UTF-8, Java Properties, and Localized HTML (Backblaze runs in 11 languages!)
  • JavaScript, CSS, Ajax
  • jQuery, Bootstrap
  • JSON, XML
  • Understanding of cross-browser compatibility issues and ways to work around them
  • Basic SEO principles and ensuring that applications will adhere to them
  • Learning about third party marketing and sales tools through reading documentation. Our systems include Google Tag Manager, Google Analytics, Salesforce, and Hubspot

Struts, Java, JSP, Servlet and Apache Tomcat are a plus, but not required.

We’re looking for someone that is:

  • Passionate about building friendly, easy to use Interfaces and APIs.
  • Likes to work closely with other engineers, support, and marketing to help customers.
  • Is comfortable working independently on a mutually agreed upon prioritization queue (we don’t micromanage, we do make sure tasks are reasonably defined and scoped).
  • Diligent with quality control. Backblaze prides itself on giving our team autonomy to get work done, do the right thing for our customers, and keep a pace that is sustainable over the long run. As such, we expect everyone that checks in code that is stable. We also have a small QA team that operates as a secondary check when needed.

Backblaze Employees Have:

  • Good attitude and willingness to do whatever it takes to get the job done
  • Strong desire to work for a small fast, paced company
  • Desire to learn and adapt to rapidly changing technologies and work environment
  • Comfort with well behaved pets in the office

This position is located in San Mateo, California. Regular attendance in the office is expected. Backblaze is an Equal Opportunity Employer and we offer competitive salary and benefits, including our no policy vacation policy.

If this sounds like you
Send an email to [email protected] with:

  1. Front End Dev​ in the subject line
  2. Your resume attached
  3. An overview of your relevant experience

The post Wanted: Front End Developer appeared first on Backblaze Blog | Cloud Storage & Cloud Backup.

faker.js – Tool To Generate Fake Data For Testing

Post Syndicated from Darknet original http://feedproxy.google.com/~r/darknethackers/~3/0ycnOUzHDxU/

faker.js is a tool to generate fake data in Node.js and in the browser, it has a lot of different data types to enable you to generate very customised and complete sets of fake or mock data for testing purposes. It also supports multiple languages and locales and can generate a lot of data types […]

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Jack – Drag & Drop Clickjacking Tool For PoCs

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Jack is a Drag and Drop web-based Clickjacking Tool for the assistance of development in PoCs made with static HTML and JavaScript. Jack is web based and requires either a web server to serve its HTML and JS content or can be run locally. Typically something like Apache will suffice but anything that is able […]

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