693 items tagged “javascript”
2010
Comet (long polling) for all browsers using ScriptCommunicator. More Comet from the Plurk team: 80 lines of dependency free JavaScript implementing long polling using script tags (hence working cross-domain) across IE6+, Firefox, WebKit and Opera. The clever bit is the code to detect loading errors. It doesn’t try to fix the infinite loading indicator problem—is that still a cromulent usability concern?
Plurk: Instant conversations using Comet (via) Plurk’s comet implementation sounds pretty amazing. They’re using a single quad-core server with 32GB of RAM running 8 Node.js instances to serve long-polled comet to 100,000+ simultaneous users. They switched to Node from Java JBoss/Netty and found the new solution used 10 times less memory.
jQuery source viewer. A neat way of browsing the source code of jQuery itself, complete with hyperlinks to other jQuery methods. Kind of a single-purpose IDE. I can see myself using this a lot.
HTML 5 audio player demo. Scott Andrew’s experiments with the HTML5 audio element (and jQuery)—straight forward and works a treat in Safari, but Firefox doesn’t support MP3. Presumably it’s not too hard to set up a fallback for Ogg.
Hot Code Loading in Node.js. Blaine Cook’s patch for Node.js that enables Erlang-style hot code loading, so you can switch out your application logic without restarting the server or affecting existing requests. This could make deploying new versions of Node applications trivial. I’d love to see a Node hosting service that allows you to simply upload a script file and have it execute on the Web.
Dojo 1.4.1 vs jQuery 1.4.2pre on Taskspeed. John Resig’s reponse. When JavaScript libraries compete on performance, everybody wins.
Dojo: Still Twice As Fast When It Matters Most. Alex Russell shows how Dojo out-performs jQuery on the TaskSpeed benchmark, which attempts to represent common tasks in real-world applications and has had code that have been optimised by the development teams behind each of the libraries.
jQuery 1.4 Released. With comprehensive release notes. Huge performance improvements and a ton of very sensible enhancements to the API—far too many to summarise.
2009
qTip. Advanced tooltip plugin for jQuery, including borders and pointers created using CSS. Very flexible (we used this for the latest MP expenses application) but a little on the heavy side, weighing in at 38KB when minified.
tipsy. Simple Facebook-style tooltip plugin for jQuery.
Orderly JSON. Essentially the JSON equivalent of RelaxNG’s compact syntax—a pleasant mini-language for describing JSON objects which compiles to the more verbose JSONSchema format.
jQuery.require() implementation. John Resig has added a new jQuery.require() function to a jQuery development branch, for release as part of jQuery 1.4. The commit on GitHub has an extensive discussion attached to it (scroll to the bottom).
getElementsByTagName(). Dean Edwards rolls a hand-rolled getElementsByTagName function for use with DOM fragments (which don’t provide the method). His code is a nice example of a tightly written tree walker using the low level DOM API.
Real time online activity monitor example with node.js and WebSocket. A neat exploration of Node.js—first hooking a “tail -f” process up to an HTTP push stream, then combining that with HTML 5 WebSockets to achieve reliable streaming.
jQuery 1.4 Alpha 1 Released. Impressively the new version contains no new features at all (correct me if I’m wrong), instead focusing on significant performance improvements to the existing API.
Google Analytics goes async. This is excellent news—the latest version of the Google Analytics JavaScript is designed to allow for asynchronous loading, so it won’t hold up the rendering of your page. Analytics and banner ads are the two worst offenders when it comes to slowing down page loads. Now if only a banner ad vendor would follow suit...
flXHR. I was looking for something like this recently, glad to see it exists. flXHR is a drop-in replacement for regular XMLHttpRequest which uses an invisible Flash shim to allow cross-domain calls to be made, taking advantage of the Flash crossdomain.xml security model.
LABjs: new hotness for script loading. Created in collaboration with Steve Souders, LABjs is a JavaScript loading library which makes it easy to have scripts download in parallel while still ensuring that they execute sequentially where required to ensure dependencies are met. It’s unclear how you would decide to use this over concatenating all scripts together in to a single file.
Request Routing With URI Templates in Node.JS. I quite like this approach (though the implementation is a bit “this” heavy for my taste). JavaScript has no equivalent to Python’s raw strings, so regular expression based routing ala Django ends up being a bit uglier in JavaScript. URI template syntax is more appealing.
Node.js is genuinely exciting
I gave a talk on Friday at Full Frontal, a new one day JavaScript conference in my home town of Brighton. I ended up throwing away my intended topic (JSONP, APIs and cross-domain security) three days before the event in favour of a technology which first crossed my radar less than two weeks ago.
[... 2,025 words]Deep Tracing of Internet Explorer. dynaTrace Ajax looks like an awesome tool. For once, Internet Explorer has a development tool that other browsers can be jealous of.
node.js at JSConf.eu (PDF). node.js creator Ryan Dahl’s presentation at this year’s JSConf.eu. The principle philosophy is that I/O in web applications should be asynchronous—for everything. No blocking for database calls, no blocking for filesystem access. JavaScript is a mainstream programming language with a culture of callback APIs (thanks to the DOM) and is hence ideally suited to building asynchronous frameworks.
Going evented with Node.js. Comprehensive Node.js tutorial—from basic principles to installation and writing a simple Twitter search command-line client application.
node.js. “Evented I/O for V8 JavaScript”—a JavaScript environment built on top of the super-fast V8 engine which provides event-based IO functionality for building highly concurrent TCP and HTTP servers. The API design is superb—everything is achieved using JavaScript events and callbacks (even regular file IO) and the small standard library ships with comprehensive support for HTTP and DNS. Overall it’s very similar to Twisted and friends, but JavaScript’s anonymous function syntax feels more natural than the Python equivalent. It compiles cleanly on Snow Leopard. Definitely a project to watch.
It’s interesting to me how much [Closure] feels like a more advanced version of Dojo in many ways. There's a familiar package system, the widgets are significantly more mature, and Julie and Ojan's Editor component rocks. The APIs will feel familiar (if verbose) to Dojo users, the class hierarchies seem natural, and Closure even uses Acme, the Dojo CSS selector engine.
Introducing Closure Tools. Google have released the pure-JavaScript library, apparently used for Gmail, Google Docs and Google Maps. It comes with a powerful JavaScript optimiser tool with linting built in and an accompanying Firebug extension to ensure the obfuscated code it produces can still be debugged. There’s also a template system which precompiles down to JavaScript and can also be called from Java.
Introducing the YUI 3 Gallery. Write a plugin for YUI3, BSD license it and sign a CLA and Yahoo! will push your module out to their CDN and make it loadable using the YUI().use() statement. They’re coordinating the submissions using GitHub.
JSLitmus. “A lightweight tool for creating ad-hoc JavaScript benchmark tests”. Includes an ingenious hack for graphing the results—it generates a Google Chart, then provides a TinyURL for viewing that chart in the future. The TinyURL is generated by pointing an inconspicuous iframe at the TinyURL API and letting the user copy-and-paste the resulting shortened URL directly out of the iframe.
Underscore.js. A new library of functional programming primitives for JavaScript—each, map, all, any, inject, detect etc. Unlike some similar libraries this one doesn’t extend the built-in objects, instead opting to bind the new functions to the underscore symbol. A jQuery-style noConflict() option is available if even that is too much namespace pollution for you.
Introducing BERT and BERT-RPC. Justification for inventing a brand new serialisation protocol: Thrift and Protocol Buffers both use IDLs and code generation, XML “is not convertible to a simple unambiguous data structure in any language I’ve ever used” and JSON lacks support for unencoded binary data. The result is BERT—Binary ERlang Term—which extracts a format from Erlang in much the same way that JSON extracted one from JavaScript.