Simon Willison’s Weblog

NYT Flash-based visualizations work again. The New York Times are using the open source Ruffle Flash emulator—built using Rust, compiled to WebAssembly—to get their old archived data visualization interactives working again. # 21st January 2024, 5:58 am

Internet Archive Software Library: Flash (via) A fantastic new initiative from the Internet Archive: they’re now archiving Flash (.swf) files and serving them for modern browsers using Ruffle, a Flash Player emulator written in Rust and compiled to WebAssembly. They are fully interactive and audio works too. Considering the enormous quantity of creative material released in Flash over the decades this helps fill a big hole in the Internet’s cultural memory. # 19th November 2020, 9:19 pm

2020 Web Milestones (via) A lot of stuff is happening in 2020! Mike Sherov rounds it up—highlights include the release of Chromium Edge (Microsoft’s Chrome-powered browser for Windows 7+), Web Components supported in every major browser, Deno 1.x, SameSite Cookies turned on by default (which should dramatically reduce CSRF exposure) and Python 2 and Flash EOLs. # 24th January 2020, 4:43 am

CSRF: Flash + 307 redirect = Game Over. Here’s the exploit that Django and Rails both just released fixes for. It’s actually a flaw in the Flash player. Flash isn’t meant to be able to make cross-domain HTTP requests with custom HTTP headers unless the crossdomain.xml file on the other domain allows them to, but it turns out a 307 redirect (like a 302, but allows POST data to be forwarded) confuses the Flash player in to not checking the crossdomain.xml on the host it is being redirect to. # 10th February 2011, 10:07 pm

tobeytailor’s gordon. Another Flash runtime in pure JavaScript project, released back in January. Not quite as advanced as Smokescreen yet (it doesn’t have an audio implementation) but already available as open source under an MIT license. # 29th May 2010, 11:57 am

Smokescreen demo: a Flash player in JavaScript. Chris Smoak’s Smokescreen, “a Flash player written in JavaScript”, is an incredible piece of work. It runs entirely in the browser, reads in SWF binaries, unzips them (in native JS), extracts images and embedded audio and turns them in to base64 encoded data:uris, then stitches the vector graphics back together as animated SVG. Open up the Chrome Web Inspector while the demo is running and you can see the SVG changing in real time. Smokescreen even implements its own ActionScript bytecode interpreter. It’s stated intention is to allow Flash banner ads to execute on the iPad and iPhone, but there are plenty of other interesting applications (such as news site infographics). The company behind it have announced plans to open source it in the near future. My one concern is performance—the library is 175 KB and over 8,000 lines of JavaScript which might cause problems on low powered mobile devices. # 29th May 2010, 11:32 am

Realtime Election Tweets. Jay Caines-Gooby’s realtime election tweet service, using Node.js, nginx and WebSocket with a Flash fallback. # 6th May 2010, 9:20 pm

Flash CS5 will export to HTML5 Canvas. This looks pretty awesome—Illustrator CS5 and Flash CS5 can export to a new “FXG” format, and Adobe are providing a JavaScript library to load that format via Ajax and render the contents (including Flash animations) in a canvas element. Could be great for displaying newspaper infographics on the iPad. # 11th April 2010, 6:33 pm

flashblockdetector. Mark Pilgrim’s JavaScript library for detecting if the user has a Flash blocker enabled, such as FlashBlock for Firefox and Chrome or ClickToFlash for Safari. One good use of this would be to inform users that they need to opt-in to Flash for unobtrusive Flash enhancements (such as invisible audio players) to work on that page. # 13th March 2010, 10:44 am

ClearMaps: A Mapping Framework for Data Visualization. An open source library for map visualisations using ActionScript, with an Adobe AIR based encoding tool for translating data from shapefiles in to vector data suitable for use with the library. # 28th February 2010, 3:52 pm

HTML5 video markup, compatibility and playback. Everything you need to know about embedding HTML5 video on a page, complete with multiple codecs to cover the various supporting browsers and a fallback to Flash. # 11th February 2010, 5:49 pm

Plupload (via) Fantastic new open source project from the team behind TinyMCE. Plupload offers a cross-browser JavaScript File uploading API that handles multiple file uploads, client-side progress meters, type filtering and even client-side image resizing and drag-and-drop from the desktop. It achieves all of this by providing backends for Flash, Silverlight, Google Gears, HTML5 and Browserplus and picking the most capable available option. # 10th February 2010, 12:53 pm

SublimeVideo—HTML5 Video Player. Still a fair way to go (no Firefox support yet, and they plan to add a Flash fallback for IE) but in Safari this is pretty extraordinary. Smooth video, beautiful UI, full window mode and full screen mode in the latest WebKit nightlies. I’d go as far as saying that this is the nicest online video implementation I’ve seen (at least on the Mac). # 2nd February 2010, 9:50 am

Who Can Do Something About Those Blue Boxes? John Gruber makes the case for the fading significance of Flash, brought about by Apple’s point-blank refusal to support it on the iPhone or iPad. “Flash is no longer ubiquitous. There’s a big difference between “everywhere” and “almost everywhere”.” # 31st January 2010, 12:05 pm

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. # 26th November 2009, 12:52 pm

Cross-domain policy file usage recommendations for Flash Player. One of the best explanations of the security implications of crossdomain.xml files I’ve seen. If you host a crossdomain.xml file with allow-access-from domain=“*” and don’t understand all of the points described here, you probably have a nasty security vulnerability. # 5th November 2009, 4:24 pm

Facebook and MySpace security: backdoor wide open, millions of accounts exploitable (via) Amazingly, both services had wide open holes in their crossdomain.xml files. Facebook were serving allow-access-from-domain=“*” in the crossdomain.xml file on one of their subdomains (a subdomain that still had access to the user’s profile information) while MySpace were opting in farm.sproutbuilder.com, a service which allowed anyone to upload arbitrary SWF files. # 5th November 2009, 9:47 am

Adobe is Bad for Open Government. The problem isn’t just that PDFs are a bad way of sharing data, it’s that Adobe have been actively lobbying the US government to use their PDF and Flash formats for open government initiatives. # 1st November 2009, 12:51 pm

Developing for the Apple iPhone using Flash. A brilliant feat of engineering: Adobe worked around Apple’s “no runtime allowed” rules by writing a compiler front end for LLVM that compiles ActionScript 3 to ARM assembly code, and apparently ported the regular Flash drawing APIs as well. # 5th October 2009, 9:15 pm

svgweb. Awesome. I’ve been having a lot of fun with SVG for dynamic graphics recently (maps in particular), and hoping someone builds an SVG renderer in Flash so I could serve up SVG files for IE. Brad Neuberg and team have done exactly that. # 22nd August 2009, 10:42 pm

You Deleted Your Cookies? Think Again (via) Flash cookies last longer than browser cookies and are harder to delete. Some services are sneakily “respawning” their cookies—if you clear the regular tracking cookie it will be reinstated from the Flash data next time you visit a page. # 17th August 2009, 3:23 pm

Towards a Standard for Django Session Messages. I completely agree that Django’s user.message_set (which I helped design) is unfit for purpose, but I don’t think sessions are the right solution for messages sent to users. A signed cookie containing either the full message or a key referencing the message body on the server is a much more generally useful solution as it avoids the need for a round trip to a persistent store entirely. # 19th June 2009, 9:57 pm

SWFUpload jQuery Plugin. Nice looking plugin around an invisible Flash shim that provides multiple file uploads and client-side progress indicators. # 16th June 2009, 11:46 am

Fixing IE by porting Canvas to Flash. Implementing canvas using Flash is an obvious step, but personally I’m much more interested in an SVG renderer using Flash that finally brings non-animated SVGs to IE. # 15th March 2009, 1:34 pm

Visualising Radio, pushing, not pulling. The BBC’s new radio player uses Comet over a Flash XMLsocket connection transport, with an ActiveMQ message queue behind the scenes. I’d like to know what server they’re using to broadcast out to the XMLsocket connections. # 13th January 2009, 12:59 am

Noncontiguous area cartograms. a.k.a. really funky data visualisation maps. Includes lots of examples, plus ActionScript 3 source code. # 8th December 2008, 6:03 pm

Wario Land: Shake It—Amazing footage! Some virals really do deserve linking to. # 26th September 2008, 4:46 pm

What the Heck is the Open Web? Brad Neuberg is seeking a two sentence definition. Bonus points for answering the following: “If Adobe were to open source Flex/Flash, or Microsoft Silverlight, would that be the Open Web? If so, why? If not, why not?” # 22nd July 2008, 1:33 am

Running C and Python Code on The Web. Adobe are working on a toolchain to compile C code to target the Tamarin VM in Flash. This will allow existing C code (from CPython to Quake) to execute in a safe sandbox in the browser. # 4th July 2008, 8:26 am

Poking new holes with Flash Crossdomain Policy File. This is an old article from 2006 which describes the crossdomain.xml hidden in a GIF exploit I referred to in an earlier post (scroll down to the appendix for an example). As far as I know the Flash Player’s crossdomain.xml parser has been tightened up since. # 1st July 2008, 4:12 pm