- From: Mercurial notifier <cvsmail@w3.org>
- Date: Tue, 10 Jul 2012 18:05:51 +0000
- To: public-dap-commits@w3.org
changeset: 142:22d946f1b9e2 tag: tip user: Robin Berjon <robin@berjon.com> date: Tue Jul 10 14:05:46 2012 -0400 files: wi-addendum-local-services/Overview.html description: fixing another helpful contribution from hg diff -r d39273e3dee0 -r 22d946f1b9e2 wi-addendum-local-services/Overview.html --- a/wi-addendum-local-services/Overview.html Tue Jul 10 11:37:21 2012 -0400 +++ b/wi-addendum-local-services/Overview.html Tue Jul 10 14:05:46 2012 -0400 @@ -576,583 +576,4 @@ </p> </section> </body> -</html>======= -<!DOCTYPE html> -<html> - <head> - <title>Web Intents Addendum - Local Services</title> - <meta http-equiv='Content-Type' content='text/html;charset=utf-8'/> - <!-- - === NOTA BENE === - For the three scripts below, if your spec resides on dev.w3 you can check them - out in the same tree and use relative links so that they'll work offline, - --> - <script src='http://www.w3.org/Tools/respec/respec-w3c-common' class='remove'></script> - <script class='remove'> - var respecConfig = { - // specification status (e.g. WD, LCWD, NOTE, etc.). If in doubt use ED. - specStatus: "ED", - - // the specification's short name, as in http://www.w3.org/TR/short-name/ - shortName: "Web Intents-UPnP addendum", - - // if your specification has a subtitle that goes below the main - // formal title, define it here - // subtitle : "an excellent document", - - // if you wish the publication date to be other than today, set this - // publishDate: "2009-08-06", - - // if the specification's copyright date is a range of years, specify - // the start date here: - // copyrightStart: "2005" - - // if there is a previously published draft, uncomment this and set its YYYY-MM-DD date - // and its maturity status - // previousPublishDate: "1977-03-15", - // previousMaturity: "WD", - - // if there a publicly available Editor's Draft, this is the link - // edDraftURI: "http://dev.w3.org/2009/dap/ReSpec.js/documentation.html", - - // if this is a LCWD, uncomment and set the end of its review period - // lcEnd: "2009-08-05", - - // if you want to have extra CSS, append them to this list - // it is recommended that the respec.css stylesheet be kept - extraCSS: ["http://dev.w3.org/2009/dap/ReSpec.js/css/respec.css"], - - // editors, add as many as you like - // only "name" is required - editors: [ - { name: "Claes Nilsson", - company: "Sony Mobile", companyURL: "http://www.sonymobile.com/se/" }, - ], - - // authors, add as many as you like. - // This is optional, uncomment if you have authors as well as editors. - // only "name" is required. Same format as editors. - - //authors: [ - // { name: "Your Name", url: "http://example.org/", - // company: "Your Company", companyURL: "http://example.com/" }, - //], - - // - edDraftURI: "http://w3c-test.org/dap/wi-addendum-local-services/", - - // name of the WG - wg: "DAP/Web Apps Web Intents task force", - - // URI of the public WG page - wgURI: "http://www.w3.org/2009/dap/", - - // name (without the @w3c.org) of the public mailing to which comments are due - wgPublicList: "public-web-intents", - - // URI of the patent status for this WG, for Rec-track documents - // !!!! IMPORTANT !!!! - // This is important for Rec-track documents, do not copy a patent URI from a random - // document unless you know what you're doing. If in doubt ask your friendly neighbourhood - // Team Contact. - wgPatentURI: "", - }; - </script> - </head> - <body> - <section id='abstract'> - This specification is an addendum to Web Intents, [[!WEBINTENTS]], that defines how Web Intents enabled User Agents can discover and communicate - with local Web Intents Services. - </section> - - <section class='informative'> - <h2>Introduction</h2> - <p> - Web Intents,[[!WEBINTENTS]], is a service discovery and light-weight RPC mechanism for web applications. The concept enables rich integration between web applications. - A typical Web Intents scenario is: - </p> - <ol> - <li>Web Intents Services register their intention to handle an action for the user </li> - <li>A web application requests to start an action (share, edit, pick, view, ...)</li> - <li>The user selects which service to handle the action</li> - </ol> - <p> - A Web Intents Service is represented by a web page that declaratively marks itself as providing handling functionality for particular intents. Users register Web Intents Services - by visiting web pages that contain registration markup. - However, the strength of Web Intents is the ability to provide web applications with access to Services residing not only in the cloud but also in local environments. - </p> - <p> - This specification defines optional extensions to Web Intents enabled User Agents to discover and dynamically register local Web Intents - Services. Note that all details of the specific low level protocols used to discover and communicate with the local services are hidden to - the Client Web Applications. - </p> - <p> - The following code illustrates how a web application containing links to videos, can initiate video playback by creating and invoking a "video intent" as defined in [[!WEBINTENTS]]. - This code is the same irrespective of whether the Service executing the intent action is a cloud based Service or a local Service. - </p> - <pre class="example sh_javascript_dom"> - - // Create a new intent -var intent = new Intent( "http://webintents.org/view","video/mp4",{ "src":videoCanvas.src, "img": videoCanvas.poster}); - -// Start intents picker -navigator.startActivity(intent, - // On Result - function(intentData) {console.log("player.html: On Result" + intentData);}, - // On Failure - function(intentData) {console.log("player.html: On Failure" + intentData);}); - </pre> - <p> - The example below briefly describes the steps taken when a Service on a local network, e.g. UPnP or mDNS, device is discovered and selected by - the user. - </p> - - <ol> - <li>Triggered by navigator.startActivity the User Agent will start local network discovery of Web Intents Services.</li> - <li>Replies from Web Intents enabled devices contain a URL to a Web Intents document, containing Web Intents Service registration - markup, in the device. </li> - <li>The Web Intents documents are retrieved by the User Agent and the dynamically registered Services are visible in the Web Intents Service picker. </li> - <li>User selects Service.</li> - <li>User Agent retrieves the Service page from the the Web Intents local network device and invokes it. </li> - <li>The Service page handles the intent. </li> - <li>When handling the intent is finished, the Service page issues window.intent.postResult and closes itself. </li> - </ol> - - </section> - - <section id="conformance"> - <p> - This specification defines conformance criteria that apply to: - <ul> - <li><dfn>UPnP enabled User Agent</dfn>: A <a>UPnP enabled User Agent</a> MUST support Web Intents [[!WEBINTENTS]] and the conformance criteria - stated in this specification. </li> - <li><dfn>UPnP enabled device</dfn>: A <a>UPnP enabled device</a> MUST support [[!UPNP-DEVICEARCH]] and the conformance criteria - stated in this specification. </li> - </ul> - - <p> - TBD definitions of User Agents and devices for other local discovery and communication technologies... - </p> - </p> - <p> - Implementations that use ECMAScript to implement the APIs defined in - this specification must implement them in a manner consistent with the - ECMAScript Bindings defined in the Web IDL specification [[!WEBIDL]], - as this specification uses that specification and terminology. - </p> - <section> - <h2>Dependencies</h2> - <p> - This specification relies on the following specifications: - - <dl> - <dt>Web Intents</dt> - <dd>This addendum specification is dependent on and defines optional extensions to the basic Web Intents specification, [[!WEBINTENTS]]. </dd> - <dt>UPnP Device Architecture 1.0</dt> - <dd>This addendum specification is dependent on and defines vendor specific extensions to the UPnP Device Architecture 1.0 specification, [[!UPNP-DEVICEARCH]] </dd> - </dl> - - </p> - </section> - </section> - - <section> - <h2>Terminology</h2> - <p> - Web Intents related terms are used according to section "Terminology" in [[!WEBINTENTS]]. - </p> - - <section> - <h3>UPnP related terms</h3> - <p> - UPnP related terms are used according to [[!UPNP-DEVICEARCH]]. - </p> - <p> - The <a>UPnP enabled User Agent</a> has the role of a <dfn id="dfn-registration">control point</dfn> according to UPnP terminology. - </p> - <p> - The <a>UPnP enabled device</a> discovered by the <a>UPnP enabled User Agent</a> has the roles of <dfn id="dfn-registration">device</dfn> according to UPnP terminology. - </p> - </section> - - <section> - <h3>mDNS related terms</h3> - <p> - TBD... - </p> - </section> - - - </section> - - <section> - - <h2>UPnP adaptation</h2> - - <section> - - <h3><a>UPnP enabled device</a></h3> - - <p> - The <a>UPnP enabled device</a> <em class="rfc2119" title="must">must</em> support this section. - </p> - - <section> - - <h4>UPnP Web Intents serviceType</h4> - - <p> - The <a>UPnP enabled device</a> <em class="rfc2119" title="must">must</em> support the UPnP service which serviceType is the <code>urn:schemas-webintents-org:service:WebIntents:1</code> - as a vendor specific serviceType according to [[!UPNP-DEVICEARCH]]. It is vendor dependent how the <a>UPnP enabled device</a> implements the serviceType, - i.e. a device description of any deviceType could include this serviceType. - </p> - - <p> - The Web Intents serviceType <em class="rfc2119" title="must">must</em> have a dummy state variable, <code>X_State</code> of <code>ui4</code> data type to comform to [[!UPNP-DEVICEARCH]] - which requires one or more state variables in a serviceType. The <code>X_State</code> state variable is not used with a value and is never evented. - </p> - <p> - The Web Intents serviceType has no standard action. - </p> - - <p> - See below for the UPnP Service description document of the Web Intents serviceType. - </p> - - <p align="left"><img src="Example_device_and_service_description_pages/Slide2.png" alt="Service description page" width="600" height="600" ><br> - (<a href="Example_device_and_service_description_pages/Slide2.png">View as PNG</a>) - </p> - - - </section> - - <section> - - <h4>Web Intents specific SSDP headers</h4> - - <p> - The <a>UPnP enabled device</a> <em class="rfc2119" title="must">must</em> support SSDP discovery process based on standard UPnP Discovery extended with 2 additional - SSDP headers for M-SEARCH response and NOTIFY when ST/NT headers are:<code>urn:schemas-webintents-org:service:WebIntents:1</code> - </p> - - <ul> - <li> - <code>location.webintents.org</code>: <em class="rfc2119" title="required">required</em>. States the location to the Web Intents document in the <a>UPnP enabled device</a>. - If the value of this header is a relative URL the base URL is the base URL of the <code>LOCATION</code> header. - </li> - <li> - <code>action.webintents.org</code>: <em class="rfc2119" title="optional">optional</em>. If supported, states the Web Intents - <code>action</code> of the supported Web Intents Services and <em class="rfc2119" title="must">must</em> - match the <code>action</code> attributes of the Service registration markup in the Web Intents document. To support more than - one Web Intents <code>action</code> the action strings <em class="rfc2119" title="must">must</em> be separated with - one or more commas. Commas included in action strings <em class="rfc2119" title="must">must</em> be percent-encoded as - defined in [[!RFC3986]], section-2.1. - <br /> <br /> - This header allows the <a>UPnP enabled User Agent</a> to filter received SSDP messages so that the <a>UPnP enabled User Agent</a>s only have to - retrieve Web Intents documents for matching Web Intents Actions. - </li> - </ul> - - </section> - - <section> - - <h4>Web Intents document</h4> - - <p> - The <a>UPnP enabled device</a> <em class="rfc2119" title="must">must</em> store Web Intents documents for the Web Intents Services the <a>UPnP enabled device</a> supports. - Web Intents documents are html pages that contain Web Intents Service registration markup according to the rules for Web Intents Service registration defined - by [[!WEBINTENTS]]. They may also contain Service handler code for Services registered within the same document. - </p> - - </section> - - <section> - - <h4>Web Intents Service pages</h4> - - <p> - The <a>UPnP enabled device</a> <em class="rfc2119" title="must">must</em> store a Web Intents Service page for each Service that is - referred in Web Intents documents through <code>href</code> attributes in the registration markup. - </p> - <p> - Service pages contain Service handler code and fulfills the rules for Web Intents Services as defined by [[!WEBINTENTS]]. - </p> - - </section> - - </section> - - <section> - - <h3><a>UPnP enabled User Agent</a></h3> - - <p> - The <a>UPnP enabled User Agent</a> <em class="rfc2119" title="must">must</em> support discovery of <a>UPnP enabled device<a>s through SSDP Discovery or through Advertisement - or through both methods according to [[!UPNP-DEVICEARCH]] and according to the Web Intents serviceType and Web Intents specific SSDP headers - defined in this specification, section 4.1. - </p> - - <p> - The sections below describe typical steps using these methods. - </p> - <section class='informative'> - <h4>Dynamic Service registration based on M-SEARCH</h4> - <p> - The section describes the discovery process based on standard UPnP M-SEARCH multicast request. - </p> - - <p> - When the navigator.startActivity method [[!WEBINTENTS]] is called, the <a>UPnP enabled User Agent</a> runs the following steps: - </p> - - <ol class="rule"> - <li> - Send a multicast request with the method M-SEARCH in the format specified by [[!UPNP-DEVICEARCH]]. - <br /> - The <code>ST</code> header is set to: <code>urn:schemas-webintents-org:service:WebIntents:1</code> - </li> - <br /> - <li> - For each matching M-SEARCH response, i.e. the response ST header is <code>urn:schemas-webintents-org:service:WebIntents:1</code> and the <code>action.webintents.org</code> - header, if present, matches the Action of the invoked intent, - the <a>UPnP enabled User Agent</a> attempts to retrieve the Web Intents document from the discovered <a>UPnP enabled device</a>. - The value of the <code>location.webintents.org</code> header is the location for the Web Intents document. - If this value is a relative URL the <a>UPnP enabled User Agent</a> uses the base URL of the <code>LOCATION</code> header as base URL for the location of the - Web Intents document. - <br /> <br /> - If the <a>UPnP enabled User Agent</a> fails to retrieve the Web Intents document it silently disregards the discovered Service. - <br /> <br /> - If the <code>action.webintents.org</code> header is present and does not match the <code>action</code> attributes of the Services registered in the retrieved Web Intents - document the <a>UPnP enabled User Agent</a> silently disregards the discovered Service. - </li> - <br /> - <li> - It is expected that the Web Intents document contains registration markup and the <a>UPnP enabled User Agent</a> interprets this - registration markup according to the rules for registration defined by [[!WEBINTENTS]] and register the Services accordingly. - </li> - <br /> - <li> - The <a>UPnP enabled User Agent</a> makes each dynamically registered Service available for selection - by the user, typically by making them visible and selectable in a Web Intents Service picker. - </li> - <br /> - <li> - Based on user selection of a dynamically registered Service the <a>UPnP enabled User Agent</a> loads the - Service handler code as defined by the <code>href</code> attribute in the registration markup for this Service according to the rules for - loading Service pages defined in [[!WEBINTENTS]]. - </li> - - </ol> - - </section> - - <section class='informative'> - <h4>Dynamic Service registration based on NOTIFY</h4> - <p> - This section describes the discovery process based on standard UPnP Advertisement with NOTIFY message. - </p> - - <p> - The <a>UPnP enabled User Agent</a> <em class="rfc2119" title="may">may</em> continously listen and act on advertisments according to the following steps: - </p> - <ol class="rule"> - - <li> - The <a>UPnP enabled User Agent</a> maintains a list of announced services based on received SSDP NOTIFY messages - with <code>NT</code> header equal to <code>urn:schemas-webintents-org:service:WebIntents:1</code>. - </li> - <br /> - <li> - When the navigator.startActivity method [[!WEBINTENTS]] is called the <a>UPnP enabled User Agent</a> checks the list - of of announced services for a service with an <code>action.webintents.org</code> header that matches the Action of the invoked intent. - </li> - <br /> - <li> - For each match the <a>UPnP enabled User Agent</a> attempts to retrieve the Web Intents document document from the discovered <a>UPnP enabled device</a>. The <a>UPnP enabled User Agent</a> - may also attempt to retrieve the Web Intents document for announced services without an <code>action.webintents.org</code> header. - The location of the Web Intents document is the value of the <code>location.webintents.org</code> header. If this value is a relative URL the - base URL is the base URL of the <code>LOCATION</code> header. - <br /> <br /> - If the <a>UPnP enabled User Agent</a> fails to retrieve the Web Intents document it silently disregards the discovered Service. - <br /> <br /> - If the <code>action.webintents.org</code> header does not match the <code>action</code> attribute in the retrieved Web Intents document - the <a>UPnP enabled User Agent</a> silently disregards the discovered Service. - </li> - <br /> - <li> - It is expected that the Web Intents document contains registration markup and the <a>UPnP enabled User Agent</a> interprets the - Web Intents document according to the rules for registration defined by [[!WEBINTENTS]] and register the Services accordingly. - </li> - <br /> - <li> - The <a>UPnP enabled User Agent</a> makes each dynamically registered Service available for selection - by the user, typically by making them visible and selectable in a Web Intents Service picker. - </li> - <br /> - <li> - Based on user selection of a dynamically registered Service the <a>UPnP enabled User Agent</a> loads the - Service handler code as defined by the <code>href</code> attribute in the registration markup for this Service according to the rules for - loading Service pages defined in [[!WEBINTENTS]]. - </li> - </ol> - - <p class="note"> - Power consumption in battery powered devices should be considered. If power consumption is severe continuously listening to SSDP advertisement in the background - should not be used.. - </p> - - </section> - - <section class='informative'> - <h4>Support for Web Intents and UPnP</h4> - <p> - In addition to the normative statements defined in this specification it is assumed that <a>UPnP enabled User Agent</a>s that comply to this specification - support Web Intents according to [[!WEBINTENTS]] and UPnP Discovery, Description and Control according to [[!UPNP-DEVICEARCH11]]. - However, it is implementation dependent whether this is supported natively in the User Agent or supported through some external component, - e.g. an in-device web server. - </p> - </section> - - <section class='informative'> - - <h4>Service availability management</h4> - - <p> - The <a>UPnP enabled User Agent</a> must manage the availability of UPnP services. For example detect when contact with a <a>UPnP enabled device</a> is lost through standard - UPnP life cycle management and remove a previously discovered and registered Service from the Service picker. However, for battery powered devices - power consumption must be considered and long lasting "keep alive" sessions" should be avoided. - </p> - - </section> - - </section> - - - - </section> - - <section> - - <h2>mDNS adaptation</h2> - - <p> - - This section describes how the User Agent handles Web Intents Services provided by local devices supporting mDNS. - </p> - - <p> - TBD.... - </p> - - - </section> - - - <section class='informative'> - <h2>APIs / protocols Client - Service </h2> - <p> - The APIs / protocols for interaction between Client and Service pages are not defined by this specification. It is assumed that Web Intents - based APIs and protocols will be standardized by W3C and that these will be applicable for Client and Service applications running on User Agents that - comply to this specification. Different use cases will require different ways of interaction patterns between Client and Service. - </p> - - <p> - Examples: - </p> - <ul> - <li> - A Client application invoking a "View" intent provides, as intent payload data, a link to a video to be displayed at the remote <a>UPnP enabled device</a>. - The Service application takes full control of the video playback by providing control buttons and sends UPnP commands to the remote device. - So in this case there the simple "API" just gives the link to the video to play. - </li> - <li> - Some use cases require a longer lasting relation between the Client and Service applications. By using the MessagePort[] attribute of the intent object - a message channel can be established between the Client and Service page. This message channel can be used to run Service specific protocols, - for example a protocol that allows the Client application to send simple video playback control commands to a Service application. - </li> - </ul> - - </section> - - <section class='informative appendix'> - <h2>Examples and scenarios</h2> - <section> - <h3>View and control video on remote device through Service page control buttons</h3> - <p> - The following scenario describes how a Client page uses Web Intents to discover a remote video view service. The Service page - contains the UI for controlling the video playback. - </p> - - <p align="left"><img src="Example_scenario_1/Slide1.png" alt="Example scenario 1/Slide1" width="700" height="700" ><br> - (<a href="Example_scenario_1/Slide1.png">View as PNG</a>) - </p> - - <p align="left"><img src="Example_scenario_1/Slide2.png" alt="Example scenario 1/Slide2" width="700" height="700" ><br> - (<a href="Example_scenario_1/Slide2.png">View as PNG</a>) - </p> - - <p align="left"><img src="Example_scenario_1/Slide3.png" alt="Example scenario 1/Slide3" width="700" height="700" ><br> - (<a href="Example_scenario_1/Slide3.png">View as PNG</a>) - </p> - </section> - - <section> - <h3>View and control video on remote device through Client page control buttons</h3> - <p> - The following scenario describes how a Client page uses Web Intents to discover a remote video view service. The UI stays in the Client page, - which contains the UI controls for the video playback. - </p> - - <p class="issue"> - This scenario assumes the possibility to have hidden/background Service pages or Service pages that are visible inline the Client page. - Currently [[!WEBINTENTS]] does not allow this but W3C DAP Action http://www.w3.org/2009/dap/track/actions/519 should add a proposal for a hidden disposition. - </p> - - <p align="left"><img src="Example_scenario_2/Slide1.png" alt="Example scenario 2/Slide1" width="700" height="700" ><br> - (<a href="Example_scenario_2/Slide1.png">View as PNG</a>) - </p> - - <p align="left"><img src="Example_scenario_2/Slide2.png" alt="Example scenario 2/Slide2" width="700" height="700" ><br> - (<a href="Example_scenario_2/Slide2.png">View as PNG</a>) - </p> - - <p align="left"><img src="Example_scenario_2/Slide3.png" alt="Example scenario 2/Slide3" width="700" height="700" ><br> - (<a href="Example_scenario_2/Slide3.png">View as PNG</a>) - </p> - - <p align="left"><img src="Example_scenario_2/Slide4.png" alt="Example scenario 2/Slide4" width="700" height="700" ><br> - (<a href="Example_scenario_2/Slide4.png">View as PNG</a>) - </p> - </section> - - - - <section> - <h3>Example of Web Intents document</h3> - - <p align="left"><img src="Example1_registration_page/Slide1.png" alt="Example1 registration page" width="280" height="280" ><br> - (<a href="Example1_registration_page/Slide1.png">View as PNG</a>) - </p> - </section> - - <section> - <h3>Example of UPnP Device description document</h3> - <p align="left"><img src="Example_device_and_service_description_pages/Slide1.png" alt="Example device and service description pages/Slide1" width="600" height="600" ><br> - (<a href="Example_device_and_service_description_pages/Slide1.png">View as PNG</a>) - </p> - </section> - - </section> - - <section class='appendix'> - <h3>Acknowledgements</h3> - <p> - Many thanks to Sony Mobile colleagues Anders Isberg, Anders Edenbrandt and Björn Ekberg - for all support. - <br /> <br /> - Many thanks to Robin Berjon for making our lives so much easier with his cool specification editing tool. - </p> - </section> - </body> </html>
Received on Tuesday, 10 July 2012 18:05:59 UTC