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diff --git a/plugins/af_readability/vendor/fivefilters/readability.php/test/test-pages/002/expected.html b/plugins/af_readability/vendor/fivefilters/readability.php/test/test-pages/002/expected.html deleted file mode 100644 index 564f9a915..000000000 --- a/plugins/af_readability/vendor/fivefilters/readability.php/test/test-pages/002/expected.html +++ /dev/null @@ -1,418 +0,0 @@ -<div id="content-main"> - <article role="article"> - <p>For more than a decade the Web has used XMLHttpRequest (XHR) to achieve - asynchronous requests in JavaScript. While very useful, XHR is not a very - nice API. It suffers from lack of separation of concerns. The input, output - and state are all managed by interacting with one object, and state is - tracked using events. Also, the event-based model doesn’t play well with - JavaScript’s recent focus on Promise- and generator-based asynchronous - programming.</p> - <p>The <a href="https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API">Fetch API</a> intends - to fix most of these problems. It does this by introducing the same primitives - to JS that are used in the HTTP protocol. In addition, it introduces a - utility function <code>fetch()</code> that succinctly captures the intention - of retrieving a resource from the network.</p> - <p>The <a href="https://fetch.spec.whatwg.org">Fetch specification</a>, which - defines the API, nails down the semantics of a user agent fetching a resource. - This, combined with ServiceWorkers, is an attempt to:</p> - <ol> - <li>Improve the offline experience.</li> - <li>Expose the building blocks of the Web to the platform as part of the - <a href="https://extensiblewebmanifesto.org/">extensible web movement</a>.</li> - </ol> - <p>As of this writing, the Fetch API is available in Firefox 39 (currently - Nightly) and Chrome 42 (currently dev). Github has a <a href="https://github.com/github/fetch">Fetch polyfill</a>.</p> - -<h2>Feature detection</h2> - - <p>Fetch API support can be detected by checking for <code>Headers</code>,<code>Request</code>, <code>Response</code> or <code>fetch</code> on - the <code>window</code> or <code>worker</code> scope.</p> - -<h2>Simple fetching</h2> - - <p>The most useful, high-level part of the Fetch API is the <code>fetch()</code> function. - In its simplest form it takes a URL and returns a promise that resolves - to the response. The response is captured as a <code>Response</code> object.</p> - <div><pre>fetch<span>(</span><span>"/data.json"</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>res<span>)</span> <span>{</span> - <span>// res instanceof Response == true.</span> - <span>if</span> <span>(</span>res.<span>ok</span><span>)</span> <span>{</span> - res.<span>json</span><span>(</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>data<span>)</span> <span>{</span> - console.<span>log</span><span>(</span>data.<span>entries</span><span>)</span><span>;</span> - <span>}</span><span>)</span><span>;</span> - <span>}</span> <span>else</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Looks like the response wasn't perfect, got status"</span><span>,</span> res.<span>status</span><span>)</span><span>;</span> - <span>}</span> -<span>}</span><span>,</span> <span>function</span><span>(</span>e<span>)</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Fetch failed!"</span><span>,</span> e<span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>Submitting some parameters, it would look like this:</p> - <div><pre>fetch<span>(</span><span>"http://www.example.org/submit.php"</span><span>,</span> <span>{</span> - method<span>:</span> <span>"POST"</span><span>,</span> - headers<span>:</span> <span>{</span> - <span>"Content-Type"</span><span>:</span> <span>"application/x-www-form-urlencoded"</span> - <span>}</span><span>,</span> - body<span>:</span> <span>"firstName=Nikhil&favColor=blue&password=easytoguess"</span> -<span>}</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>res<span>)</span> <span>{</span> - <span>if</span> <span>(</span>res.<span>ok</span><span>)</span> <span>{</span> - alert<span>(</span><span>"Perfect! Your settings are saved."</span><span>)</span><span>;</span> - <span>}</span> <span>else</span> <span>if</span> <span>(</span>res.<span>status</span> <span>==</span> <span>401</span><span>)</span> <span>{</span> - alert<span>(</span><span>"Oops! You are not authorized."</span><span>)</span><span>;</span> - <span>}</span> -<span>}</span><span>,</span> <span>function</span><span>(</span>e<span>)</span> <span>{</span> - alert<span>(</span><span>"Error submitting form!"</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>The <code>fetch()</code> function’s arguments are the same as those passed - to the - <br> -<code>Request()</code> constructor, so you may directly pass arbitrarily - complex requests to <code>fetch()</code> as discussed below.</p> - -<h2>Headers</h2> - - <p>Fetch introduces 3 interfaces. These are <code>Headers</code>, <code>Request</code> and - <br> -<code>Response</code>. They map directly to the underlying HTTP concepts, - but have - <br>certain visibility filters in place for privacy and security reasons, - such as - <br>supporting CORS rules and ensuring cookies aren’t readable by third parties.</p> - <p>The <a href="https://fetch.spec.whatwg.org/#headers-class">Headers interface</a> is - a simple multi-map of names to values:</p> - <div><pre><span>var</span> content <span>=</span> <span>"Hello World"</span><span>;</span> -<span>var</span> reqHeaders <span>=</span> <span>new</span> Headers<span>(</span><span>)</span><span>;</span> -reqHeaders.<span>append</span><span>(</span><span>"Content-Type"</span><span>,</span> <span>"text/plain"</span> -reqHeaders.<span>append</span><span>(</span><span>"Content-Length"</span><span>,</span> content.<span>length</span>.<span>toString</span><span>(</span><span>)</span><span>)</span><span>;</span> -reqHeaders.<span>append</span><span>(</span><span>"X-Custom-Header"</span><span>,</span> <span>"ProcessThisImmediately"</span><span>)</span><span>;</span></pre> - </div> - <p>The same can be achieved by passing an array of arrays or a JS object - literal - <br>to the constructor:</p> - <div><pre>reqHeaders <span>=</span> <span>new</span> Headers<span>(</span><span>{</span> - <span>"Content-Type"</span><span>:</span> <span>"text/plain"</span><span>,</span> - <span>"Content-Length"</span><span>:</span> content.<span>length</span>.<span>toString</span><span>(</span><span>)</span><span>,</span> - <span>"X-Custom-Header"</span><span>:</span> <span>"ProcessThisImmediately"</span><span>,</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>The contents can be queried and retrieved:</p> - <div><pre>console.<span>log</span><span>(</span>reqHeaders.<span>has</span><span>(</span><span>"Content-Type"</span><span>)</span><span>)</span><span>;</span> <span>// true</span> -console.<span>log</span><span>(</span>reqHeaders.<span>has</span><span>(</span><span>"Set-Cookie"</span><span>)</span><span>)</span><span>;</span> <span>// false</span> -reqHeaders.<span>set</span><span>(</span><span>"Content-Type"</span><span>,</span> <span>"text/html"</span><span>)</span><span>;</span> -reqHeaders.<span>append</span><span>(</span><span>"X-Custom-Header"</span><span>,</span> <span>"AnotherValue"</span><span>)</span><span>;</span> - -console.<span>log</span><span>(</span>reqHeaders.<span>get</span><span>(</span><span>"Content-Length"</span><span>)</span><span>)</span><span>;</span> <span>// 11</span> -console.<span>log</span><span>(</span>reqHeaders.<span>getAll</span><span>(</span><span>"X-Custom-Header"</span><span>)</span><span>)</span><span>;</span> <span>// ["ProcessThisImmediately", "AnotherValue"]</span> - -reqHeaders.<span>delete</span><span>(</span><span>"X-Custom-Header"</span><span>)</span><span>;</span> -console.<span>log</span><span>(</span>reqHeaders.<span>getAll</span><span>(</span><span>"X-Custom-Header"</span><span>)</span><span>)</span><span>;</span> <span>// []</span></pre> - </div> - <p>Some of these operations are only useful in ServiceWorkers, but they provide - <br>a much nicer API to Headers.</p> - <p>Since Headers can be sent in requests, or received in responses, and have - various limitations about what information can and should be mutable, <code>Headers</code> objects - have a <strong>guard</strong> property. This is not exposed to the Web, but - it affects which mutation operations are allowed on the Headers object. - <br>Possible values are:</p> - <ul> - <li>“none”: default.</li> - <li>“request”: guard for a Headers object obtained from a Request (<code>Request.headers</code>).</li> - <li>“request-no-cors”: guard for a Headers object obtained from a Request - created - <br>with mode “no-cors”.</li> - <li>“response”: naturally, for Headers obtained from Response (<code>Response.headers</code>).</li> - <li>“immutable”: Mostly used for ServiceWorkers, renders a Headers object - <br>read-only.</li> - </ul> - <p>The details of how each guard affects the behaviors of the Headers object - are - <br>in the <a href="https://fetch.spec.whatwg.org">specification</a>. For example, - you may not append or set a “request” guarded Headers’ “Content-Length” - header. Similarly, inserting “Set-Cookie” into a Response header is not - allowed so that ServiceWorkers may not set cookies via synthesized Responses.</p> - <p>All of the Headers methods throw TypeError if <code>name</code> is not a - <a href="https://fetch.spec.whatwg.org/#concept-header-name">valid HTTP Header name</a>. The mutation operations will throw TypeError - if there is an immutable guard. Otherwise they fail silently. For example:</p> - <div><pre><span>var</span> res <span>=</span> Response.<span>error</span><span>(</span><span>)</span><span>;</span> -<span>try</span> <span>{</span> - res.<span>headers</span>.<span>set</span><span>(</span><span>"Origin"</span><span>,</span> <span>"http://mybank.com"</span><span>)</span><span>;</span> -<span>}</span> <span>catch</span><span>(</span>e<span>)</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Cannot pretend to be a bank!"</span><span>)</span><span>;</span> -<span>}</span></pre> - </div> - -<h2>Request</h2> - - <p>The Request interface defines a request to fetch a resource over HTTP. - URL, method and headers are expected, but the Request also allows specifying - a body, a request mode, credentials and cache hints.</p> - <p>The simplest Request is of course, just a URL, as you may do to GET a - resource.</p> - <div><pre><span>var</span> req <span>=</span> <span>new</span> Request<span>(</span><span>"/index.html"</span><span>)</span><span>;</span> -console.<span>log</span><span>(</span>req.<span>method</span><span>)</span><span>;</span> <span>// "GET"</span> -console.<span>log</span><span>(</span>req.<span>url</span><span>)</span><span>;</span> <span>// "http://example.com/index.html"</span></pre> - </div> - <p>You may also pass a Request to the <code>Request()</code> constructor to - create a copy. - <br>(This is not the same as calling the <code>clone()</code> method, which - is covered in - <br>the “Reading bodies” section.).</p> - <div><pre><span>var</span> copy <span>=</span> <span>new</span> Request<span>(</span>req<span>)</span><span>;</span> -console.<span>log</span><span>(</span>copy.<span>method</span><span>)</span><span>;</span> <span>// "GET"</span> -console.<span>log</span><span>(</span>copy.<span>url</span><span>)</span><span>;</span> <span>// "http://example.com/index.html"</span></pre> - </div> - <p>Again, this form is probably only useful in ServiceWorkers.</p> - <p>The non-URL attributes of the <code>Request</code> can only be set by passing - initial - <br>values as a second argument to the constructor. This argument is a dictionary.</p> - <div><pre><span>var</span> uploadReq <span>=</span> <span>new</span> Request<span>(</span><span>"/uploadImage"</span><span>,</span> <span>{</span> - method<span>:</span> <span>"POST"</span><span>,</span> - headers<span>:</span> <span>{</span> - <span>"Content-Type"</span><span>:</span> <span>"image/png"</span><span>,</span> - <span>}</span><span>,</span> - body<span>:</span> <span>"image data"</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>The Request’s mode is used to determine if cross-origin requests lead - to valid responses, and which properties on the response are readable. - Legal mode values are <code>"same-origin"</code>, <code>"no-cors"</code> (default) - and <code>"cors"</code>.</p> - <p>The <code>"same-origin"</code> mode is simple, if a request is made to another - origin with this mode set, the result is simply an error. You could use - this to ensure that - <br>a request is always being made to your origin.</p> - <div><pre><span>var</span> arbitraryUrl <span>=</span> document.<span>getElementById</span><span>(</span><span>"url-input"</span><span>)</span>.<span>value</span><span>;</span> -fetch<span>(</span>arbitraryUrl<span>,</span> <span>{</span> mode<span>:</span> <span>"same-origin"</span> <span>}</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>res<span>)</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Response succeeded?"</span><span>,</span> res.<span>ok</span><span>)</span><span>;</span> -<span>}</span><span>,</span> <span>function</span><span>(</span>e<span>)</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Please enter a same-origin URL!"</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>The <code>"no-cors"</code> mode captures what the web platform does by default - for scripts you import from CDNs, images hosted on other domains, and so - on. First, it prevents the method from being anything other than “HEAD”, - “GET” or “POST”. Second, if any ServiceWorkers intercept these requests, - they may not add or override any headers except for <a href="https://fetch.spec.whatwg.org/#simple-header">these</a>. - Third, JavaScript may not access any properties of the resulting Response. - This ensures that ServiceWorkers do not affect the semantics of the Web - and prevents security and privacy issues that could arise from leaking - data across domains.</p> - <p><code>"cors"</code> mode is what you’ll usually use to make known cross-origin - requests to access various APIs offered by other vendors. These are expected - to adhere to - <br>the <a href="https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS">CORS protocol</a>. - Only a <a href="https://fetch.spec.whatwg.org/#concept-filtered-response-cors">limited set</a> of - headers is exposed in the Response, but the body is readable. For example, - you could get a list of Flickr’s <a href="https://www.flickr.com/services/api/flickr.interestingness.getList.html">most interesting</a> photos - today like this:</p> - <div><pre><span>var</span> u <span>=</span> <span>new</span> URLSearchParams<span>(</span><span>)</span><span>;</span> -u.<span>append</span><span>(</span><span>'method'</span><span>,</span> <span>'flickr.interestingness.getList'</span><span>)</span><span>;</span> -u.<span>append</span><span>(</span><span>'api_key'</span><span>,</span> <span>'<insert api key here>'</span><span>)</span><span>;</span> -u.<span>append</span><span>(</span><span>'format'</span><span>,</span> <span>'json'</span><span>)</span><span>;</span> -u.<span>append</span><span>(</span><span>'nojsoncallback'</span><span>,</span> <span>'1'</span><span>)</span><span>;</span> - -<span>var</span> apiCall <span>=</span> fetch<span>(</span><span>'https://api.flickr.com/services/rest?'</span> <span>+</span> u<span>)</span><span>;</span> - -apiCall.<span>then</span><span>(</span><span>function</span><span>(</span>response<span>)</span> <span>{</span> - <span>return</span> response.<span>json</span><span>(</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>json<span>)</span> <span>{</span> - <span>// photo is a list of photos.</span> - <span>return</span> json.<span>photos</span>.<span>photo</span><span>;</span> - <span>}</span><span>)</span><span>;</span> -<span>}</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>photos<span>)</span> <span>{</span> - photos.<span>forEach</span><span>(</span><span>function</span><span>(</span>photo<span>)</span> <span>{</span> - console.<span>log</span><span>(</span>photo.<span>title</span><span>)</span><span>;</span> - <span>}</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>You may not read out the “Date” header since Flickr does not allow it - via - <br> -<code>Access-Control-Expose-Headers</code>.</p> - <div><pre>response.<span>headers</span>.<span>get</span><span>(</span><span>"Date"</span><span>)</span><span>;</span> <span>// null</span></pre> - </div> - <p>The <code>credentials</code> enumeration determines if cookies for the other - domain are - <br>sent to cross-origin requests. This is similar to XHR’s <code>withCredentials</code> - <br>flag, but tri-valued as <code>"omit"</code> (default), <code>"same-origin"</code> and <code>"include"</code>.</p> - <p>The Request object will also give the ability to offer caching hints to - the user-agent. This is currently undergoing some <a href="https://github.com/slightlyoff/ServiceWorker/issues/585">security review</a>. - Firefox exposes the attribute, but it has no effect.</p> - <p>Requests have two read-only attributes that are relevant to ServiceWorkers - <br>intercepting them. There is the string <code>referrer</code>, which is - set by the UA to be - <br>the referrer of the Request. This may be an empty string. The other is - <br> -<code>context</code> which is a rather <a href="https://fetch.spec.whatwg.org/#requestcredentials">large enumeration</a> defining - what sort of resource is being fetched. This could be “image” if the request - is from an - <img>tag in the controlled document, “worker” if it is an attempt to load a - worker script, and so on. When used with the <code>fetch()</code> function, - it is “fetch”.</p> - -<h2>Response</h2> - - <p><code>Response</code> instances are returned by calls to <code>fetch()</code>. - They can also be created by JS, but this is only useful in ServiceWorkers.</p> - <p>We have already seen some attributes of Response when we looked at <code>fetch()</code>. - The most obvious candidates are <code>status</code>, an integer (default - value 200) and <code>statusText</code> (default value “OK”), which correspond - to the HTTP status code and reason. The <code>ok</code> attribute is just - a shorthand for checking that <code>status</code> is in the range 200-299 - inclusive.</p> - <p><code>headers</code> is the Response’s Headers object, with guard “response”. - The <code>url</code> attribute reflects the URL of the corresponding request.</p> - <p>Response also has a <code>type</code>, which is “basic”, “cors”, “default”, - “error” or - <br>“opaque”.</p> - <ul> - <li><code>"basic"</code>: normal, same origin response, with all headers exposed - except - <br>“Set-Cookie” and “Set-Cookie2″.</li> - <li><code>"cors"</code>: response was received from a valid cross-origin request. - <a href="https://fetch.spec.whatwg.org/#concept-filtered-response-cors">Certain headers and the body</a>may be accessed.</li> - <li><code>"error"</code>: network error. No useful information describing - the error is available. The Response’s status is 0, headers are empty and - immutable. This is the type for a Response obtained from <code>Response.error()</code>.</li> - <li><code>"opaque"</code>: response for “no-cors” request to cross-origin - resource. <a href="https://fetch.spec.whatwg.org/#concept-filtered-response-opaque">Severely<br> - restricted</a> - </li> - </ul> - <p>The “error” type results in the <code>fetch()</code> Promise rejecting with - TypeError.</p> - <p>There are certain attributes that are useful only in a ServiceWorker scope. - The - <br>idiomatic way to return a Response to an intercepted request in ServiceWorkers - is:</p> - <div><pre>addEventListener<span>(</span><span>'fetch'</span><span>,</span> <span>function</span><span>(</span>event<span>)</span> <span>{</span> - event.<span>respondWith</span><span>(</span><span>new</span> Response<span>(</span><span>"Response body"</span><span>,</span> <span>{</span> - headers<span>:</span> <span>{</span> <span>"Content-Type"</span> <span>:</span> <span>"text/plain"</span> <span>}</span> - <span>}</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>As you can see, Response has a two argument constructor, where both arguments - are optional. The first argument is a body initializer, and the second - is a dictionary to set the <code>status</code>, <code>statusText</code> and <code>headers</code>.</p> - <p>The static method <code>Response.error()</code> simply returns an error - response. Similarly, <code>Response.redirect(url, status)</code> returns - a Response resulting in - <br>a redirect to <code>url</code>.</p> - -<h2>Dealing with bodies</h2> - - <p>Both Requests and Responses may contain body data. We’ve been glossing - over it because of the various data types body may contain, but we will - cover it in detail now.</p> - <p>A body is an instance of any of the following types.</p> - <ul> - <li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/ArrayBuffer">ArrayBuffer</a> - </li> - <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/ArrayBufferView">ArrayBufferView</a> (Uint8Array - and friends)</li> - <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/Blob">Blob</a>/ - <a href="https://developer.mozilla.org/en-US/docs/Web/API/File">File</a> - </li> - <li>string</li> - <li><a href="https://url.spec.whatwg.org/#interface-urlsearchparams">URLSearchParams</a> - </li> - <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/FormData">FormData</a> – - currently not supported by either Gecko or Blink. Firefox expects to ship - this in version 39 along with the rest of Fetch.</li> - </ul> - <p>In addition, Request and Response both offer the following methods to - extract their body. These all return a Promise that is eventually resolved - with the actual content.</p> - <ul> - <li><code>arrayBuffer()</code> - </li> - <li><code>blob()</code> - </li> - <li><code>json()</code> - </li> - <li><code>text()</code> - </li> - <li><code>formData()</code> - </li> - </ul> - <p>This is a significant improvement over XHR in terms of ease of use of - non-text data!</p> - <p>Request bodies can be set by passing <code>body</code> parameters:</p> - <div><pre><span>var</span> form <span>=</span> <span>new</span> FormData<span>(</span>document.<span>getElementById</span><span>(</span><span>'login-form'</span><span>)</span><span>)</span><span>;</span> -fetch<span>(</span><span>"/login"</span><span>,</span> <span>{</span> - method<span>:</span> <span>"POST"</span><span>,</span> - body<span>:</span> form -<span>}</span><span>)</span></pre> - </div> - <p>Responses take the first argument as the body.</p> - <div><pre><span>var</span> res <span>=</span> <span>new</span> Response<span>(</span><span>new</span> File<span>(</span><span>[</span><span>"chunk"</span><span>,</span> <span>"chunk"</span><span>]</span><span>,</span> <span>"archive.zip"</span><span>,</span> - <span>{</span> type<span>:</span> <span>"application/zip"</span> <span>}</span><span>)</span><span>)</span><span>;</span></pre> - </div> - <p>Both Request and Response (and by extension the <code>fetch()</code> function), - will try to intelligently <a href="https://fetch.spec.whatwg.org/#concept-bodyinit-extract">determine the content type</a>. - Request will also automatically set a “Content-Type” header if none is - set in the dictionary.</p> - -<h3>Streams and cloning</h3> - - <p>It is important to realise that Request and Response bodies can only be - read once! Both interfaces have a boolean attribute <code>bodyUsed</code> to - determine if it is safe to read or not.</p> - <div><pre><span>var</span> res <span>=</span> <span>new</span> Response<span>(</span><span>"one time use"</span><span>)</span><span>;</span> -console.<span>log</span><span>(</span>res.<span>bodyUsed</span><span>)</span><span>;</span> <span>// false</span> -res.<span>text</span><span>(</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>v<span>)</span> <span>{</span> - console.<span>log</span><span>(</span>res.<span>bodyUsed</span><span>)</span><span>;</span> <span>// true</span> -<span>}</span><span>)</span><span>;</span> -console.<span>log</span><span>(</span>res.<span>bodyUsed</span><span>)</span><span>;</span> <span>// true</span> - -res.<span>text</span><span>(</span><span>)</span>.<span>catch</span><span>(</span><span>function</span><span>(</span>e<span>)</span> <span>{</span> - console.<span>log</span><span>(</span><span>"Tried to read already consumed Response"</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - <p>This decision allows easing the transition to an eventual <a href="https://streams.spec.whatwg.org/">stream-based</a> Fetch - API. The intention is to let applications consume data as it arrives, allowing - for JavaScript to deal with larger files like videos, and perform things - like compression and editing on the fly.</p> - <p>Often, you’ll want access to the body multiple times. For example, you - can use the upcoming <a href="http://slightlyoff.github.io/ServiceWorker/spec/service_worker/index.html#cache-objects">Cache API</a> to - store Requests and Responses for offline use, and Cache requires bodies - to be available for reading.</p> - <p>So how do you read out the body multiple times within such constraints? - The API provides a <code>clone()</code> method on the two interfaces. This - will return a clone of the object, with a ‘new’ body. <code>clone()</code> MUST - be called before the body of the corresponding object has been used. That - is, <code>clone()</code> first, read later.</p> - <div><pre>addEventListener<span>(</span><span>'fetch'</span><span>,</span> <span>function</span><span>(</span>evt<span>)</span> <span>{</span> - <span>var</span> sheep <span>=</span> <span>new</span> Response<span>(</span><span>"Dolly"</span><span>)</span><span>;</span> - console.<span>log</span><span>(</span>sheep.<span>bodyUsed</span><span>)</span><span>;</span> <span>// false</span> - <span>var</span> clone <span>=</span> sheep.<span>clone</span><span>(</span><span>)</span><span>;</span> - console.<span>log</span><span>(</span>clone.<span>bodyUsed</span><span>)</span><span>;</span> <span>// false</span> - - clone.<span>text</span><span>(</span><span>)</span><span>;</span> - console.<span>log</span><span>(</span>sheep.<span>bodyUsed</span><span>)</span><span>;</span> <span>// false</span> - console.<span>log</span><span>(</span>clone.<span>bodyUsed</span><span>)</span><span>;</span> <span>// true</span> - - evt.<span>respondWith</span><span>(</span>cache.<span>add</span><span>(</span>sheep.<span>clone</span><span>(</span><span>)</span><span>)</span>.<span>then</span><span>(</span><span>function</span><span>(</span>e<span>)</span> <span>{</span> - <span>return</span> sheep<span>;</span> - <span>}</span><span>)</span><span>;</span> -<span>}</span><span>)</span><span>;</span></pre> - </div> - -<h2>Future improvements</h2> - - <p>Along with the transition to streams, Fetch will eventually have the ability - to abort running <code>fetch()</code>es and some way to report the progress - of a fetch. These are provided by XHR, but are a little tricky to fit in - the Promise-based nature of the Fetch API.</p> - <p>You can contribute to the evolution of this API by participating in discussions - on the <a href="https://whatwg.org/mailing-list">WHATWG mailing list</a> and - in the issues in the <a href="https://www.w3.org/Bugs/Public/buglist.cgi?product=WHATWG&component=Fetch&resolution=---">Fetch</a> and - <a href="https://github.com/slightlyoff/ServiceWorker/issues">ServiceWorker</a>specifications.</p> - <p>For a better web!</p> - <p><em>The author would like to thank Andrea Marchesini, Anne van Kesteren and Ben<br> -Kelly for helping with the specification and implementation.</em> - </p> - - </article> - - - </div>
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