W3C home > Mailing lists > Public > public-device-apis@w3.org > September 2011

Fwd: Draft Proposal for Streams API

From: Robin Berjon <robin@berjon.com>
Date: Fri, 23 Sep 2011 11:32:34 +0200
To: DAP <public-device-apis@w3.org>
Message-Id: <5993CA12-15AF-4743-B6D6-F0423FD2557A@berjon.com>
FYI. This is an interesting approach that could be useful for some of our work.

Begin forwarded message:
> Resent-From: public-webapps@w3.org
> From: Adrian Bateman <adrianba@microsoft.com>
> Date: September 22, 2011 20:35:17 GMT+02:00
> To: "Web Applications Working Group WG (public-webapps@w3.org)" <public-webapps@w3.org>
> Cc: Feras Moussa <ferasm@microsoft.com>
> Subject: Draft Proposal for Streams API
> archived-at: <http://www.w3.org/mid/104E6B5B6535E849970CDFBB1C5216EB4E17C253@TK5EX14MBXC136.redmond.corp.microsoft.com>
> There has been discussion in this group now and again about the need for stream
> support as part of the File APIs including recently in the threads about Streaming
> Blobs [1] and XHR streaming [2]. I've also had several private conversations with
> members of the WG about the need we see for this kind of stream support.
> Initially, we thought that supporting a streaming Blob was the correct solution
> but we ran into a number of issues with this as we investigated further. First of
> all, people were confused about using the term "Blob" to represent something of
> unknown size. Secondly, we received guidance from a number of people to keep the
> two concepts of Blob and Stream separate.
> Back in March, we provided some suggestions about using streams in the context of
> Media Capture and Speech with our submission to the HTML Speech XG [3].
> Specifically at that time we said:
>  We propose the addition of a stream type. While this document does
>  not present a detailed design for this type, we assume a Stream is
>  an object that:
>    1. Has a content type;
>    2. Has unspecified length;
>    3. Can generally be used in the same places Blob can be used, for
>       example URL.createObjectURL().
> Over the last six months, we have refined our thinking further and would like to
> submit a proposal for review by the working group that provides that detailed
> design. We believe that this work is part of the chartered deliverables for File
> API (and includes XHR support):
>    Streams API - http://html5labs.com/streamsapi/
> We recognise that there are a number of different proposals for using stream-like
> objects elsewhere in the web platform, usually for very specific use cases. What
> we have tried to define here is a Stream object that is as generic as the Blob
> object defined in the File API spec. 
> As we started building applications with richer access to devices on the system
> including files we found the lack of support for an object representing
> asynchronous data of (initially) unknown size was important. Section 11 of the
> proposal provides examples of the scenarios we have in mind. To start to address
> this gap, we have implemented a preview of this mechanism in IE10 Platform
> Preview 3 behind a vendor prefix (e.g. MSStream) to gain more implementation
> experience.
> We look forward to hearing feedback on this proposal, which we've framed mostly
> as a delta against existing drafts in this working group.
> Thanks,
> Adrian.
> [1] http://lists.w3.org/Archives/Public/public-webapps/2011JulSep/0725.html
> [2] http://lists.w3.org/Archives/Public/public-webapps/2011JulSep/0741.html
> [3] http://lists.w3.org/Archives/Public/www-archive/2011Mar/att-0001/microsoft-api-draft-final.html#streams

Robin Berjon - http://berjon.com/ - @robinberjon
Received on Friday, 23 September 2011 09:32:59 UTC

This archive was generated by hypermail 2.3.1 : Monday, 23 October 2017 14:53:50 UTC