Simon Willison’s Weblog

DNode: Asynchronous Remote Method Invocation for Node.js and the Browser. Mind-bendingly clever. DNode lets you expose a JavaScript function so that it can be called from another machine using a simple JSON-based network protocol. That’s relatively straight-forward... but DNode is designed for asynchronous environments, and so also lets you pass callback functions which will be translated in to references and used to make remote method invocations back to your original client. And to top it off, there’s a browser client library so you can perform the same trick over a WebSocket between a browser and a server. # 11th July 2010, 2:27 pm

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. # 23rd December 2009, 2:44 pm

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. # 21st October 2009, 10:11 pm

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. # 17th July 2009, 9:12 am

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! # 30th June 2009, 6:08 pm

With YQL Execute, the Internet becomes your database. This is nuts (in a good way). Yahoo!’s intriguing universal SQL-style XML/JSONP web service interface now supports JavaScript as a kind of stored procedure language, meaning you can use JavaScript and E4X to screen-scrape web pages, then query the results with YQL. # 29th April 2009, 10:50 pm

Building Fast Client-side Searches. Flickr now lazily loads your entire contact list in to memory for auto-completion. Extensive benchmarking found that a control character delimited string was the fastest option for shipping thousands of contacts around as quickly as possible. # 19th March 2009, 3:35 pm

Combine JSONP and jQuery to quickly build powerful mashups. jQuery’s JSONP support is one of my favourite little-known features of the library. # 3rd March 2009, 3:17 pm

husk.org. a flickr machine tag browser (via) Flickr recently added API methods for exploring the machine tags used by the community. Paul Mison has built a neat OS X Finder style interface for exploring them, using JSONP and jQuery. # 15th December 2008, 11:24 pm

typeface.js. Outstanding hack—renders custom fonts using VML in IE and canvas in everything else, using fonts that are defined as a set of vector paths stored using JSON. # 27th October 2008, 11:45 pm

CSSHttpRequest (via) Devious cross-domain Ajax hack that uses CSS for transport (@import rules with data URIs, but it still works in IE). Similar to JSONP but safer, since JSONP can cause arbitrary JavaScript to execute. # 23rd October 2008, 6:25 pm

FriendFeed launch a real-time API. This is huge: JSONP plus long polling Comet, with “everything since X” tokens to ensure you don’t miss anything. This is the first open Comet API I’ve seen anywhere. Combine this with FriendFeed’s regular API (which allows arbitrary message posting) and you’ve got a really powerful tool for hackers who want to experiment with Comet without rigging up their own infrastructure. # 22nd October 2008, 2:18 pm

Page Inlink Analyzer (via) Here’s why I’m so keen on JSONP APIs—Eric Miraglia’s tool fires off dozens of cross-domain JSON requests to pull together information about inbound links to your site from Yahoo! Site Explorer and del.icio.us. I imagine it would have been uneconomic for him to provide the tool if it had to proxy every request through his own server. # 15th October 2008, 5:23 pm

addSizes.js: Snazzy automatic link file-size generation. Posted to Nat’s snazzy new blog: a script that uses my json-head API to grab the file size of linked documents on a page and insert those sizes in to the document. # 30th August 2008, 10:39 am

json-tinyurl. Because sometimes you want to be able to create a shorter version of a URL directly from JavaScript without hosting your own server-side proxy. # 27th August 2008, 10:58 am

jsontime. Nat and I threw this together this morning—it runs on Google App Engine and exposes Python’s pytz timezone library over JSONP. # 21st June 2008, 7:07 pm

Dopplr place googlemaps, with and without Yahoo Geo API bounding box adjustment. Dopplr uses Geonames for most geo information, but is now mixing in bounding box data from the Yahoo! Geo web service to improve the default zoom level for their maps. The JSON callback API means no server-side code is required on Dopplr’s end. # 17th May 2008, 11:35 pm

Session variables without cookies. Brilliant but terrifying hack—you can store up to 2 MB of data in window.name and it persists between multiple pages, even across domains. Doesn’t work with new tabs though, and storing JSON in it and eval()ing it is a bad idea—a malicious site could populate it before sending the user to you. # 13th May 2008, 9:59 pm

Persevere adds Comet Support. Persevere sounds neat: a RESTful HTTP/JSON data store (the interface reminds me of CouchDB) which recently gained the ability to “subscribe” to a resource and receive notifications of updates via comet. # 13th May 2008, 8:09 am

CouchDB, XML, and E4X. Brilliant—CouchDB now enables SpiderMonkey’s E4X support, meaning CouchDB views can easily query XML documents stored inside JSON objects using E4X syntax. # 5th March 2008, 12:31 am

The Art & Science of JavaScript. The JavaScript book I contributed to is now shipping! My chapter describes how to build a Flickr / Google Maps mashup entirely using client-side code (via JSON-P). # 12th January 2008, 7:05 pm

CouchDB first impressions. Jacob’s been poking at CouchDB. Inserting data is slow, but everything else looks pretty slick considering how recently the JSON / JavaScript views functionality was added. # 19th October 2007, 11:43 am

CouchDB: Thinking beyond the RDBMS. CouchDB is a fascinating project—an Erlang powered non-relational database with a JSON API that lets you define “views” (really computed tables) based on JavaScript functions that execute using map/reduce. Damien Katz, the main developer currently works for MySQL and used to work on Lotus Notes. # 3rd September 2007, 9:48 am

Fortify JavaScript Hijacking FUD. Bob Ippolito points out the flaws in the recent widely disseminated JavaScript Hijacking paper. While the paper does miss some important details, it’s good that more people are now aware of the security implications involved in serving JSON up wrapped in an array. # 5th April 2007, 10:51 pm

Javascript character set screw-ups (via) Some browsers treat JavaScript files as having the same content-type as the page from which they are linked. This could cause problems with UTF-8 encoded JSON; the workaround is serving up ASCII with unicode escape sequences. # 21st December 2006, 3:20 pm