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dmleonard618 writes: The JavaScript runtime Node.js has reached version 6.0, and unlike version 5.0 this version will receive Long Term Support (LTS). LTS is meant to provide the release with long-term stability, reliability, performance and security. The LTS will begin in October. The current LTS release will go into maintenance mode and will only receive bug, security and documentation updates. Version 5.0 of Node.js will continue to be maintained for a few more months. The latest version features improved module loading, 96% of ECMAScript 2015 features, as well as reliability and security enhancements. "The Node.js Project has done an incredible job of bringing this version to life in the timeline that we initially proposed in September 2015," said Mikeal Rogers, community manager for the Node.js Foundation. "It's important for us to continue to deliver new versions of Node.js equipped with all the cutting-edge JavaScript features to serve the needs of developers and to continue to improve the performance and stability enterprises rely on."

New submitter TFlan91 writes: The first merge of the popular Node.js and io.js repositories has been released! From the announcement: "The collaborators of the Node.js project and the members of the Node.js Foundation are proud to offer v4.0.0 for general release. This release represents countless hours of hard work encapsulated in both the Node.js project and the io.js project that are now combined in a single codebase. The Node.js project is now operated by a team of 44 collaborators, 15 of which form its Technical Steering Committee (TSC). Further, over 100 new individuals have been added to the list of people contributing code to core since v0.12.7."

New submitter jonhorvath writes: Several of the top contributors to Node.js, a popular open source run-time environment, have decided to fork the project, creating io.js as an alternative. The developers were unhappy with how cloud computing company Joyent was directing work on Node.js. Mikeal Rogers said, "We don't want to have just one person who's appointed by a company making decisions. We want contributors to have more control, to seek consensus." Here's the new repository, and a README file to go with it. A developer at Uber tweeted that they've already migrated to io.js on their production systems. It'll be interesting to see how many other sites follow.

shutdown -p now writes "Coming from the team that had previously brought you Python Tools for Visual Studio, Microsoft has announced Node.js Tools for Visual Studio, with the release of the first public alpha. NTVS is the official extension for Visual Studio that adds support for Node.js, including editing with Intellisense, debugging, profiling, and the ability to deploy Node.js websites to Windows Azure. An overview video showcases the features, and Scott Hanselman has a detailed walkthrough. The project is open source under Apache License 2.0. While the extension is published by Microsoft, it is a collaborative effort involving Microsoft, Red Gate (which previously had a private beta version of similar product called Visual Node), and individual contributors from the Node.js community."

An anonymous reader writes "For many of us our hosting providers are a way to hone our skills as well as run a business. Which provider out there gives the best bang for the buck for a FOSS developer? Virtually everybody provides Perl, PHP, Ruby, MySQL / MariaDB etc. but where can one get easy and cheap access to a stuff like NodeJS and Big Data? Companies such as Pair Networks are great but not quite on the mark with any of their service offerings for somebody looking to test out real world scenarios with these technologies from a hosted stance. Obviously hosting from home is always an option but that has the penalty of administration, backup, DR planning, bigger security footprint etc. and for those of us whose time is balanced between making money and friends / family time that's not very appealing."

Michael Ross writes "Since its introduction in 1994, JavaScript has largely been utilized within web browsers, which limited JavaScript programmers to client-side development. Yet with the recent introduction of Node.js, those programmers can leverage their skills and experience for server-side efforts. Node.js is an event-based framework for creating network applications — particularly those for the Web. Anyone interested in learning this relatively new technology can begin with one of numerous resources, including Sams Teach Yourself Node.js in 24 Hours." Keep reading for the rest of Michael's review. Sams Teach Yourself Node.js in 24 Hours author George Ornbo pages 464 pages publisher Sams Publishing rating 7/10 reviewer Michael J. Ross ISBN 978-0672335952 summary An introduction to the Node.js framework. This book, authored by George Ornbo, was released by Sams Publishing on 15 September 2012, under the ISBN 978-0672335952. The recent publication date is promising, because Node.js is evolving rapidly, thus gradually obsoleting books written not that long ago. On the publisher's page, visitors will find a brief description of Ornbo's book, a few customer reviews, the table of contents, a sample chapter (the 14th, "A Streaming Twitter Client"), and links to purchase the print and electronic versions of the book. There is also a link to the companion site, which offers some of the same content as Pearson's page, but also has a link to download an archive file containing all the example code, nicely organized.

The book's material spans 464 pages, and is organized (shoehorned) into 24 "hours" (chapters), grouped into six parts. The first two chapters in "Getting Started" explain how the reader can download Node.js, create a "hello world" web server program, install new modules using npm (Node Packaged Modules), search for modules, locate documentation on them, and indicate module dependencies for an application. Unfortunately, the blocks of source code presented in the first examples (Listing 1.1 and Figure 2.2) are not explained in the narrative (until the fifth chapter) or even commented. Readers would likely appreciate some clues as to the nature of http.createServer, req, res, the "underscore" module, etc. — especially at the beginning of their journey. If readers are not expected to understand these details at this point, then they should be told so, to avoid any concerns that such an understanding is assumed in the subsequent chapters. The author does not explain where Node.js is installed or what changes it makes to the terminal's default path variable. On page 18, the term "project folder" is unclear: should the "underscore" module end up in hour02/example01/node_modules, or nodejs/node_modules, or nodejs/node_modules/npm/node_modules? Only later is this (partially) answered.

Chapter 3 demonstrates the complexity that arises from concurrent input/output in networked applications. This material should arguably have been presented at the beginning of the book, to better establish the purpose of Node.js, and the value to the reader of studying it. The next chapter summarizes jQuery and JavaScript callbacks, and then provides a helpful discussion of how Node.js uses the latter. The author contends that the asynchronous paradigm of Node.js is unsuitable for long-running processes, but does not explain why this is true, which would have provided some substantiation for the claim.

The second part of the book, "Basic Websites With Node.js," encompasses four more chapters. The first one discusses how to: create a simple server (using the core HTTP module), examine the response headers (generated for web pages, in different browsers and on the Linux command line), execute 301 redirects, respond to different types of requests (using the URL module), and create a simple client. Oddly, the author does not explain or even mention the sizable JSON output — the first line of which is "{ domain: null," — displayed in the reader's server terminal when the web page pointing to that server is refreshed or when the "curl -I" command is run. The next two chapters cover how to build websites using the Express framework, and are likely the first point where the reader will see some of the real-world complexity of Node.js. The eighth chapter explains how to persist data between calls to the application, including files, environment variables, and MongoDB.

Debugging, testing, and deploying are all critical topics for any application development, and are covered in the third part of the book. The author illustrates three methods of debugging: STDIO, a core module, is a lightweight method for debugging Node.js code; it allows one to output messages to the console, check the value of any variable or literal, and track function calls and responses from third-party services. Node.js provides access to the more powerful debugger of V8 (the Google Chrome JavaScript engine), which supports breakpoints and code stepping. Node Inspector, compatible with WebKit-based browsers, provides all of the above functionality, and more. The next two chapters present several modules that ease the important process of creating full-coverage tests, and demonstrate how to deploy applications to any one of three Node.js-capable cloud hosting providers (Heroku, Cloud Foundry, and Nodester).

Having covered the basics of Node.js, the author begins the fourth part of his book with two chapters that show how to use Socket.IO, WebSockets, and Express to build real-time web applications. These techniques are illustrated in the development of a chat server as well as a nickname management and messaging system. The aforementioned sample chapter extends these techniques further in working with the Twitter API to consume its real-time data, push it to the browser, and show results in a dynamic graph. This section is wrapped up with coverage primarily of JSON — specifically, how to create, consume, and send JSON-structured data.

APIs were addressed briefly in the previous section, but are explored much more deeply in the subsequent five chapters. Readers may initially conclude that the discussion of processes is elementary, but the author then shows how one could utilize that knowledge to interact with Node.js scripts, including detecting script exits and errors, sending signals and arguments to a script, generating child processes if needed, and sending messages among them. In the 18th chapter, the author goes into greater detail about Node.js's Events module, best practices, and how to generate event listeners dynamically. The buffer API may be low-level, but it is essential for storing raw binary data, as opposed to the Unicode-encoded strings that JavaScript uses within a browser. The Buffer and Stream modules are presented with plenty of helpful examples.

The last part of the book addresses miscellaneous topics, starting with CoffeeScript (a JavaScript precompiler). While CoffeeScript affords numerous benefits, it is not clear why it would deserve an entire chapter in a book dedicated to Node.js. In the next chapter, readers learn how to verify their Node.js code, add command-line executables, and then package it all up into portable modules that can be contributed to the npm registry or GitHub. The last two chapters explain how to create and configure middleware using the Connect module, and how to use Backbone.js (a front-end JavaScript framework) in conjunction with Node.js to build browser-based web applications.

Each chapter concludes with a summary (invariably a waste of space), a Q&A section, a workshop comprising quiz questions (with the answers presented immediately below it, for almost instant spoiling), and several exercises for the reader.The index at the end is missing several of the important topics discussed in the text.

The book contains many errata: "EBay" (page 1; should read "eBay"), "OSX" (page 9; presumably Mac OS X), "yaml" (page 15; should read "YAML"), "irc" (19), "led to [a] great deal" (27), "to solve Concurrency" (37), "process" (54; should read "processes"), "try and" (55; should read "try to"), "This goal" (56; should read "The goal"), "how [a] class" (56), "You will [see] the" (62), "status of [a] web server" (70), "javascripts" (77), and "then [the] name" (87). At this point, less than 20 percent into the book, it was clear that the copyeditors had done a sloppy job, so I stopped recording these flaws that should have been caught. Those first four errata suggest that "textese" is even pervading the world of technical publishing. (Strangely, there does not appear to be a place on the publisher's website for reporting errata.)

The production team should have been looking for places to cut down on the heft of the print edition. The "Try It Yourself " sections sometimes duplicate what is found in the regular text nearby — especially in the third and fourth chapters. For instance, three sets of HTML markup are repeated, as well as the surrounding discussion (pages 42 through 47).

In general, the text does not appear to have been carefully scrutinized by technical reviewers and copyeditors. Occasionally the reader is given critical information later than would be optimal, e.g., the "Watch Out" warning on page 18, provided after the reader installs a module. The writing style is noticeably awkward in countless places in the book, including several run-on sentences. (Technical authors should not be bashful in using commas when doing so would help readability.) Also, the text is littered with too many exclamation marks — as if that is going to make any narrative more exciting.

In terms of the production quality of the book, a lay-flat binding would have made it much easier to read when using both hands on the keyboard. Also, in my review copy (kindly provided by the publisher), a disappointingly large number of the pages had small black splotches of ink; fortunately, none made the text unreadable.

On the other hand, Node.js is certainly not a simple subject area, and this book is able to convey a lot of information about it. This book's forte is the extensive use of example code to illustrate the concepts being presented. Incidentally, kudos to the author for inviting the reader to contribute to the Node.js community, such as adding new modules to GitHub or updating the documentation of existing modules. Overall, readers new to Node.js would certainly benefit from working their way through this volume.

Michael J. Ross is a freelance web developer and writer.

You can purchase Sams Teach Yourself Node.js in 24 Hours from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

First time accepted submitter Mensa Babe writes "Oliver Morgan, the original author of the JavaScript Toolkit, or just 'The Toolkit' as it is known in the JavaScript community, has just announced the release of the long awaited version 1.1.0, with better documentation and added function support. Quoting the project documentation: '[JavaScript] Toolkit offers a large number of integrated methods and utilities to help enrich the javascript object library. Javascript was built originally for browsers and as such lacks a large number of data utility methods with are seen in languages such as Python and Ruby. However times have changed and JavaScript is being used more and more in backend platforms. JS Toolkit aims to bridge that gap and provide everyone a modern developer needs to produce fast, secure and tidy code quick and easily.' The Toolkit fully supports ECMAScript 5 and runs on the most important virtual machines that we have today, including Node.JS, V8, Rhino, RingoJS, and many others. It continues to be actively developed."

eldavojohn writes "Test-Driven JavaScript Development by Christian Johansen is a book that thoroughly guides the user through some of the more advanced aspects of the JavaScript language and into Test-Driven Development (TDD). Throughout it, Johansen introduces great methods and utilities like libraries to accomplish all aspects of TDD in JavaScript. The book begins with Johansen demonstrating and teaching the reader some of the more advanced aspects of JavaScript to ensure that the following lessons in TDD are well understood. The best part of the book is in the last half where Johansen builds a chat client and server completely out of JavaScript using TDD right before the readers' eyes." Keep reading for the rest of eldavojohn's review. Test-Driven JavaScript Development author Christian Johansen pages 475 publisher Addison-Wesley Professional rating 9/10 reviewer eldavojohn ISBN 978-0-321-683915 summary An in depth look at Test Driven Development in JavaScript. First off the audience for this book are JavaScript developers interested in TDD. More specifically, I would identify the audience being the poor developers that have slaved over JavaScript for endless hours only to find out that there are 'discrepancies' in how their JavaScript functions in one browser versus another (or even across versions of the same browser). If you've ever came into work one day to learn that the latest version of Internet Explorer or Mozilla Firefox now throws errors from the deep recesses of your code and you have absolutely no idea where to start, then this book may be an item of interest to you. After all, wouldn't it be great to pull up the new browser and simply watch all your tests complete code coverage with glaring red results listing specific problematic locations?

Secondly, I'd like to establish that I'm writing this review with two key assumptions. The first assumption is that JavaScript is not in and of itself evil. You might hate JavaScript (as did I at one time) but it's a very flexible and enjoyable language when you're not battling some crazy 'feature' that a particular JavaScript engine exhibits or some issue with the dreaded Document Object Model (DOM). The second assumption is that TDD is a net positive when done correctly. To some, it may be a hard sell and the author of the book is no blind preacher. TDD has its pitfalls and the book adequately notes these claiming that TDD can actually work against you if used improperly. Feel free to wage wars in the comments debating whether or not the average JavaScript monkey is capable of avoiding pitfalls and learning to write good unit tests — I'm not getting sidetracked in this review on those topics.

This book is divided into four parts. The first part of the book gives you a slight taste of testing right off the bat in chapter one (Automated Testing). Johansen starts by showing a strftime function written in JavaScript and demonstrates briefly the very clumsy standard method of testing the method in a browser. From there he introduces Assertions, Setup, Teardown and Integration Tests. What I particularly enjoyed about this book is that these key components are not forgotten after introducing them, Johansen constantly nods to the reader when duplicate code could be moved to Setup or Teardown.

Chapter two is devoted to 'turning development upside-down.' This chapter analyzes the mentality of writing a test, running the test, watching it fail, making the test pass and then refactoring to remove duplication (if necessary). Johansen stresses and restresses throughout the book that the simplest solution should be added to pass the test. Fight the urge to keep coding when you are sure what comes next and just make sure you have unit tests for that new code. The third chapter runs through many test frameworks in JavaScript and settles in on JsTestDriver weighing the pros and cons of each option. Lastly, it is demonstrated how to use JsTestDriver both inside Eclipse and from the command line (something I deeply appreciated). Chapter Four expands on this by proposing learning tests which are tests that you keep around to try out on new browsers to investigate what you depend on. I'm not entirely sold on this practice but this chapter is definitely worth the look at performance testing it provides in a few of the more complete aforementioned frameworks.

The next 145 pages are devoted to the JavaScript language itself. The reader will find out in later chapters why this was necessary but this second part felt too long and left me starving for TDD. There's a ton of great knowledge in these chapters and Johansen demonstrates an impressive display in his understanding of ECMAScript standards (all versions thereof) and all the JavaScript engines that implement them. In the following four chapters, the reader is shown the ins and outs of scope, functions, this, closures, anonymous functions, bindings, currying, namespaces, memorization, prototypical inheritance, tons of tricks with properties, mixins, strict mode and even the neat features of tddjs and JSON. What I was most impressed with in this chapter was how much care Johansen took with noting performance pitfalls in all of the above. Example: "closures in loops are generally a performance issue waiting to happen" and on for-in arrays he says "the problem illustrated above can be worked around, as we will see shortly, but not without trading off performance." Johansen seems tireless in enumerating the multitude of ways to accomplish something in JavaScript only to dissect each method critically. If you skip these sections, at least look at 6.1.3 as the bind() implementation developed there becomes critical throughout much of the book's code.

Chapter nine provides yet more dos and do nots in JavaScript with a tabbed panel example that demonstrates precisely what obtrusive JavaScript is and why it is labeled as such. Chapter ten is definitely not to be skipped over as it provides feature detection methods (specifically with regard to functions and properties) that are seen in later code snippets. Part two is devoid of any TDD yet rich in demonstrating the power of JavaScript. This is where the book loses a point for me as this seemed too long and a lot of these lessons — though informative — really seemed like they belonged in another book on the JavaScript language itself. I constantly wondered when I would start to see TDD but to a less experienced developer, these chapters are quite enlightening.

In the third part, we finally get to some TDD in which an Observer Pattern (pub/sub) is designed using tests with incremental improvements in true TDD fashion. Most importantly to the audience, we encounter our first browser inconsistencies that are tackled using TDD. This chapter illustrates how to make your first tdd.js project using the book's code and build your first tests followed up with the isolation of the code into setup and teardown functions. Rinse, wash, repeat for adding observers, checking for observers and notifying observers (all key functionality in the common observer paradigm). This is a great pragmatic example for TDD and the chapter wraps up with error checking and a new way to build a constructor. As we do this, we have to make changes to the tests and Johansen illustrates another critical part of TDD: fixing the tests after you've improved your code.

The twelfth chapter takes our Ajax friend the XMLHttpRequest object and gives it the same treatment as above. Of course, you might know it as the Msxm12.XMLHTTP.6.0 object or a variety of names so this is where our browser differences are exposed. On top of that, we're exposed to stubbing in order to test such an object. The author explores three different ways of stubbing it while building tests for GET requests. After building helpers to successfully stub this, we move on to POST, finally send data in a test and then pay attention to the testing of headers. Personally these two chapters were some of the best in the book and illustrated well a common method of utilizing TDD and stubbing to build up functional JavaScript.

Chapter thirteen builds on the previous chapter by examining polling data in JavaScript and how we might keep open a constant stream of data. Before jumping to the solution, the author investigates strategies like polling intervals and long polling which have their downfalls. We eventually come to the Comet client (which uses JSON objects) and build up our test cases that support our development of our new streaming data client. One important aspect brought up is the trick of using the Clock object to fake time. This was completely new to me and very interesting in simulating time with tick() to quickly fake and test expected lengths of time.

Chapter fourteen was definitely outside of my comfort zone. JavaScript on the server-side? Blasphemy! Johansen begins to bring together the prior elements to form a fully functional chat server all in JavaScript through TDD. In this chapter the reader is introduced to node.js and a custom version of Nodeunit the author modified to make a little more like JsTestDriver. The controller emerges through the TDD cycles. Responses to POST, adding messages, the domain model and even storage of data are given test cases to insure we are testing feature after tiny feature. Toward the end of the chapter, an interesting problem arises with our asynchronous interface. In testing it, how do we know what will result from a nested callback? Johansen introduces the concept of a Promise which is a placeholder that eventually provides a value. Instead of accepting a callback, the asynchronous method returns a promise object which is eventually fulfilled. We can now test adding messages in asynchronous manner to our chat room. The chapter builds on the chat server to passable functionality — all through TDD.

Chapter fifteen concentrates on building the chat client to the above server and in doing so provides the reader with TDD in regards to DOM manipulation and event handling. This chapter finally covers some of the more common problematic aspects of client-side JavaScript. Again, this chapter yielded many tricks that were new to me in TDD. JsTestDriver actually includes two ways to include HTML in a test and Johansen shows how to manipulate the user form on a page in order to test it automatically. The client is developed through TDD and node-paperboy is called in to serve up static files through http with Node.js. The message list displayed in the client is developed through TDD and then the same process used on the user form is done with the message form submission. The author brings in some basic CSS, Juicer and YUI Compressor to reduce all our work down into a 14kB js file containing an entire chat client. With gzip enabled it downloads at about 5kB. Potent stuff.

I was sad that more pages weren't spent on the final section. Chapter sixteen further expounds upon mocking, spies and stubbing. It lists different strategies and how to inject trouble into your code by creating stubs that blow up on purpose during testing. And we get a sort of abbreviated dose of Sinon, a mocking and stubbing library for JavaScript. The author repeats a few test cases from chapter eleven and moves on to mocking. Mocking is mentioned throughout the book but is passed over due to the amount of work required to manually mock something. The chapter ends with the author saying 'it depends' on whether you should use stubbing or mocks but it's pretty clear the author provides stubbing as he enumerates the pros and cons of each.

Chapter seventeen provides some pretty universal rules of thumb to employ when using TDD. From the obvious revealing intent by clear naming to strategies for isolating behavior, it's got good advice for succeeding with TDD. This advice aims to improve readability, generate true unit tests that stay at the unit level and avoid buggy tests. It's worth repeating that he gives a list of 'attacks' for finding deficiencies in tests: "Flip the value of the boolean expressions, remove return values, misspell or null variables and function arguments, introduce off-by-one errors in loops, mutate the value of internal variables." Introduce one deficiency and run the tests. Make sure they break when and where you would expect them to or your testing isn't as hardened as you might expect. Lastly the author recommends using JsLint (like lint for C).

There's a lot of information in this book but I think that the final examples were actually too interesting for my tastes. Often I grapple with the mundane and annoying parts of client side DOM — nothing on the server side. While this might change at some point in the future, I couldn't help but feel that the book would have been better with additional examples of more common problems than a chat client in JavaScript. I was certainly impressed with this example and it will hold the readers' attention much more than what I desire so I feel comfortable recommending this book with a 9/10 to anyone suffering from browser inconsistencies or looking to do TDD in JavaScript.

You can purchase Test-Driven JavaScript Development from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.