W3C home > Mailing lists > Public > ietf-http-wg@w3.org > April to June 2011

Re: Discussion of Blob URI Scheme for Binary Data Access | IETF

From: Mark Nottingham <mnot@mnot.net>
Date: Fri, 13 May 2011 12:52:33 +1000
Cc: ietf-http-wg@w3.org
Message-Id: <A5BD105E-4003-4376-B2CB-147D65D3476F@mnot.net>
To: arun@mozilla.com
Hi Arun,

Thanks for the heads-up.

I don't think that this group will have a *lot* to say about this, at least from an HTTP perspective, since it's only incidentally related to HTTP.

Other groups that might have some thoughts include the URI list <mailto:uri@w3.org> and the APP area list <mailto:apps-discuss@ietf.org>. I can forward to them if you'd like to avoid the overhead of subscribing.

Cheers,


On 13/05/2011, at 6:02 AM, Arun Ranganathan wrote:

> Greetings httpbis listserv!
> 
> My name is Arun Ranganathan, and I'm the current editor of the File API [1] specification; I'm also the outgoing Chair of the WebGL Working Group [2] (which brings hardware-accelerated 3D graphics to the web), and have a continued interest in allowing binary data to be securely accessed and manipulated on the web.  I'm sponsored by Mozilla.
> 
> The File API introduces the notion of a Blob object [3], which represents immutable binary data.  A file from the underlying file system can be asynchronously read as a Blob object into various data formats, for example.  The existing File interface in JavaScript inherits from Blob.
> 
> Additionally, and most significantly for this working group, the File API introduces a URI scheme for Blob access [4].  The URI scheme uses a subset of the HTTP status codes, and is designed to be used wherever "http" URIs can be used on the web.  The nascent URL API [5] which coins and revokes blob: URIs is also used with the Stream API [6] for video-conferencing use cases.
> 
> Browsers such as Chrome already implement blob: URIs [7]; Firefox's implementation will follow-suit, although is likely to be vendor-prefixed.  Our goals are to address the shortcomings of the file:/// URI scheme, which many browsers support for directory browsing of the underlying file system, but for little else (file:/// URIs are unwise choises for APIs like XMLHttpRequest, don't supply response codes, etc. etc.).  The blob: scheme was designed to address the use case of dereferencing files and binary data on the web safely, since data: URIs have shortcomings as well, and can't really be used for streams of data.
> 
> We'd welcome your feedback, including suggestions about embarking upon an IETF standardization track for this protocol.
> 
> -- A*
> 
> [1] File API: http://dev.w3.org/2006/webapi/FileAPI/
> [2] WebGL: http://www.khronos.org/webgl/
> [3] Blob defintion: http://dev.w3.org/2006/webapi/FileAPI/#dfn-Blob
> [4] blob: URI scheme: http://dev.w3.org/2006/webapi/FileAPI/#url
> [5] URL API: http://dev.w3.org/2006/webapi/FileAPI/#creating-revoking
> [6] Stream API: http://www.whatwg.org/specs/web-apps/current-work/multipage/dnd.html#stream-api
> [7] Use of blob: URI scheme in demos: http://www.html5rocks.com/tutorials/workers/basics/#toc-inlineworkers-bloburis
> 

--
Mark Nottingham   http://www.mnot.net/
Received on Friday, 13 May 2011 02:53:03 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 27 April 2012 06:51:40 GMT