713 posts tagged “javascript”
2009
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.
Official Google Webmaster Blog: A proposal for making AJAX crawlable.
It's horrible! The Google crawler would map url#!state to url?_escaped_fragment_=state, then expect your site to provide rendered HTML that reflects that state (they even go as far as to suggest running a headless browser within your web server to do this). Just stick to progressive enhancement instead, it's far less hideous. It looks like the proposal may have originated with the GWT team.
breaking links. Mike complains about sites such as Twitter and WordPress.com which mess around with Ajax and links and hence breaks the ability to command-click to open a new tab in Safari (and Chrome). I just realised that I’ve subconsciously retrained myself to right click and select “open in new tab” to avoid that exact issue.
YUI 3.0.0: First GA Release of YUI’s Next-Generation Codeline. YUI 3 has some very neat ideas—everything is dynamically loaded, so you start with a tiny bootstrap script and call YUI().use(’module-name’) to load just the code you need. Congratulations to the team.
Gmail for Mobile: Reducing Startup Latency. Cheeky iPhone optimisation trick—parsing 200 KB of JavaScript takes an iPhone 2.2 device 2.6 seconds, so Gmail embeds code components in /* comments */ in a script tag and evals them on demand later on when the features are needed.
JavaScript cannot save you. Even if it could, you should not let it, for the price of this short-term salvation is the end of what you like about the web.
On HTML 5 Drag and Drop. Francisco Tolmasky investigated HTML 5 drag and drop, which allows web apps to implement drag and drop between windows and between the browser and the desktop. He found a number of problems with the spec and proposes detailed solutions.
Scriptlets—Quick web scripts (via) From the prolific Jeff Lindsay, a pastebin-style tool for short server-side scripts written in Python, JavaScript or PHP that executes them within a Google App Engine powered sandbox. The Java code that implements the service is available on GitHub.
JSONP Memory Leak. Neil Fraser advocates iterating over and deleting every property on a JSONP script DOM node after you removeChild it from the DOM, to protect against memory leaks of “in excess of 15 MB per hour”.
EtherPad. Outstanding implementation of an online real-time collaborative text editor—basically SubEthaEdit in your browser. I can see myself using this a lot.
Reverse HTTP Demo (via) This is a bit of a brain teaser—a web server running in JavaScript in your browser which uses long polling comet to respond to incoming HTTP requests channelled through a “Reverse HTTP” proxy.
Announcing Alice and Wonderland. Continuing the RabbitMQ “stuff to do with rabbits” naming convention, Alice is a RESTful interface to RabbitMQ which exposes information about vhosts/queues/users/exchanges/etc as JSON. Wonderland is a web UI for RabbitMQ implemented as a pure Ajax application which calls Alice.
John Resig on Glow. John criticises Glow for reinventing the wheel—BBC insiders respond in the comments below.
BBC: Glow (via) The BBC have released Glow, their jQuery-like JavaScript library developed in house over the past few years. It’s open source under the Apache license.
Modernizr (via) Neat idea and an unobtrusive implementation: a JavaScript library that runs feature tests for various HTML5 features (canvas, box shadow, CSS transforms and so on) and adds classes to the HTML body element, allowing you to write CSS selectors that only apply if a feature is present. Detected features are exposed to JavaScript as boolean properties, e.g. Modernizer.multiplebgs.
Firefox 3.5 for developers. It’s out today, and the feature list is huge. Highlights include HTML 5 drag ’n’ drop, audio and video elements, offline resources, downloadable fonts, text-shadow, CSS transforms with -moz-transform, localStorage, geolocation, web workers, trackpad swipe events, native JSON, cross-site HTTP requests, text API for canvas, defer attribute for the script element and TraceMonkey for better JS performance!
Unimpressed by NodeIterator. John Resig, one of the most talented API designers I’ve ever come across, posts some well earned criticism of the document.createNodeIterator DOM traversal API.
SWFUpload jQuery Plugin. Nice looking plugin around an invisible Flash shim that provides multiple file uploads and client-side progress indicators.
Opera Unite. Opera’s big announcement: a developer preview (“labs release”) of their new web-server-in-your-browser feature, Unite. Includes an Opera-hosted proxy to help break through your firewall. The web server can be customised using server-side JavaScript running in an Opera Widget.