gecko/browser/components/thumbnails/PageThumbsProtocol.js

409 lines
11 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* PageThumbsProtocol.js
*
* This file implements the moz-page-thumb:// protocol and the corresponding
* channel delivering cached thumbnails.
*
* URL structure:
*
* moz-page-thumb://thumbnail?url=http%3A%2F%2Fwww.mozilla.org%2F
*
* This URL requests an image for 'http://www.mozilla.org/'.
*/
"use strict";
const Cu = Components.utils;
const Cc = Components.classes;
const Cr = Components.results;
const Ci = Components.interfaces;
Cu.import("resource:///modules/PageThumbs.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Services",
"resource://gre/modules/Services.jsm");
/**
* Implements the thumbnail protocol handler responsible for moz-page-thumb: URIs.
*/
function Protocol() {
}
Protocol.prototype = {
/**
* The scheme used by this protocol.
*/
get scheme() PageThumbs.scheme,
/**
* The default port for this protocol (we don't support ports).
*/
get defaultPort() -1,
/**
* The flags specific to this protocol implementation.
*/
get protocolFlags() {
return Ci.nsIProtocolHandler.URI_DANGEROUS_TO_LOAD |
Ci.nsIProtocolHandler.URI_NORELATIVE |
Ci.nsIProtocolHandler.URI_NOAUTH;
},
/**
* Creates a new URI object that is suitable for loading by this protocol.
* @param aSpec The URI string in UTF8 encoding.
* @param aOriginCharset The charset of the document from which the URI originated.
* @return The newly created URI.
*/
newURI: function Proto_newURI(aSpec, aOriginCharset) {
let uri = Cc["@mozilla.org/network/simple-uri;1"].createInstance(Ci.nsIURI);
uri.spec = aSpec;
return uri;
},
/**
* Constructs a new channel from the given URI for this protocol handler.
* @param aURI The URI for which to construct a channel.
* @return The newly created channel.
*/
newChannel: function Proto_newChannel(aURI) {
let {url} = parseURI(aURI);
let file = PageThumbsStorage.getFileForURL(url);
if (file.exists()) {
let fileuri = Services.io.newFileURI(file);
return Services.io.newChannelFromURI(fileuri);
}
return new Channel(aURI);
},
/**
* Decides whether to allow a blacklisted port.
* @return Always false, we'll never allow ports.
*/
allowPort: function () false,
classID: Components.ID("{5a4ae9b5-f475-48ae-9dce-0b4c1d347884}"),
QueryInterface: XPCOMUtils.generateQI([Ci.nsIProtocolHandler])
};
let NSGetFactory = XPCOMUtils.generateNSGetFactory([Protocol]);
/**
* A channel implementation responsible for delivering cached thumbnails.
*/
function Channel(aURI) {
this._uri = aURI;
// nsIChannel
this.originalURI = aURI;
// nsIHttpChannel
this._responseHeaders = {"content-type": PageThumbs.contentType};
}
Channel.prototype = {
_uri: null,
_referrer: null,
_canceled: false,
_status: Cr.NS_OK,
_isPending: false,
_wasOpened: false,
_responseText: "OK",
_responseStatus: 200,
_responseHeaders: null,
_requestMethod: "GET",
_requestStarted: false,
_allowPipelining: true,
_requestSucceeded: true,
/* :::::::: nsIChannel ::::::::::::::: */
get URI() this._uri,
owner: null,
notificationCallbacks: null,
get securityInfo() null,
contentType: PageThumbs.contentType,
contentCharset: null,
contentLength: -1,
get contentDisposition() {
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
},
get contentDispositionFilename() {
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
},
get contentDispositionHeader() {
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
},
open: function Channel_open() {
throw (Components.returnCode = Cr.NS_ERROR_NOT_IMPLEMENTED);
},
asyncOpen: function Channel_asyncOpen(aListener, aContext) {
if (this._isPending)
throw (Components.returnCode = Cr.NS_ERROR_IN_PROGRESS);
if (this._wasOpened)
throw (Components.returnCode = Cr.NS_ERROR_ALREADY_OPENED);
if (this._canceled)
return (Components.returnCode = this._status);
this._isPending = true;
this._wasOpened = true;
this._listener = aListener;
this._context = aContext;
if (this.loadGroup)
this.loadGroup.addRequest(this, null);
if (this._canceled)
return;
let {url} = parseURI(this._uri);
if (!url) {
this._serveThumbnailNotFound();
return;
}
PageThumbsCache.getReadEntry(url, function (aEntry) {
let inputStream = aEntry && aEntry.openInputStream(0);
if (!inputStream || !inputStream.available()) {
if (aEntry)
aEntry.close();
this._serveThumbnailNotFound();
return;
}
this._entry = aEntry;
this._pump = Cc["@mozilla.org/network/input-stream-pump;1"].
createInstance(Ci.nsIInputStreamPump);
this._pump.init(inputStream, -1, -1, 0, 0, true);
this._pump.asyncRead(this, null);
this._trackThumbnailHitOrMiss(true);
}.bind(this));
},
/**
* Serves a "404 Not Found" if we didn't find the requested thumbnail.
*/
_serveThumbnailNotFound: function Channel_serveThumbnailNotFound() {
this._responseStatus = 404;
this._responseText = "Not Found";
this._requestSucceeded = false;
this.onStartRequest(this, null);
this.onStopRequest(this, null, Cr.NS_OK);
this._trackThumbnailHitOrMiss(false);
},
/**
* Implements telemetry tracking for thumbnail cache hits and misses.
* @param aFound Whether the thumbnail was found.
*/
_trackThumbnailHitOrMiss: function Channel_trackThumbnailHitOrMiss(aFound) {
Services.telemetry.getHistogramById("FX_THUMBNAILS_HIT_OR_MISS")
.add(aFound);
},
/* :::::::: nsIStreamListener ::::::::::::::: */
onStartRequest: function Channel_onStartRequest(aRequest, aContext) {
if (!this.canceled && Components.isSuccessCode(this._status))
this._status = aRequest.status;
this._requestStarted = true;
this._listener.onStartRequest(this, this._context);
},
onDataAvailable: function Channel_onDataAvailable(aRequest, aContext,
aInStream, aOffset, aCount) {
this._listener.onDataAvailable(this, this._context, aInStream, aOffset, aCount);
},
onStopRequest: function Channel_onStopRequest(aRequest, aContext, aStatus) {
this._isPending = false;
this._status = aStatus;
this._listener.onStopRequest(this, this._context, aStatus);
this._listener = null;
this._context = null;
if (this._entry)
this._entry.close();
if (this.loadGroup)
this.loadGroup.removeRequest(this, null, aStatus);
},
/* :::::::: nsIRequest ::::::::::::::: */
get status() this._status,
get name() this._uri.spec,
isPending: function Channel_isPending() this._isPending,
loadFlags: Ci.nsIRequest.LOAD_NORMAL,
loadGroup: null,
cancel: function Channel_cancel(aStatus) {
if (this._canceled)
return;
this._canceled = true;
this._status = aStatus;
if (this._pump)
this._pump.cancel(aStatus);
},
suspend: function Channel_suspend() {
if (this._pump)
this._pump.suspend();
},
resume: function Channel_resume() {
if (this._pump)
this._pump.resume();
},
/* :::::::: nsIHttpChannel ::::::::::::::: */
get referrer() this._referrer,
set referrer(aReferrer) {
if (this._wasOpened)
throw (Components.returnCode = Cr.NS_ERROR_IN_PROGRESS);
this._referrer = aReferrer;
},
get requestMethod() this._requestMethod,
set requestMethod(aMethod) {
if (this._wasOpened)
throw (Components.returnCode = Cr.NS_ERROR_IN_PROGRESS);
this._requestMethod = aMethod.toUpperCase();
},
get allowPipelining() this._allowPipelining,
set allowPipelining(aAllow) {
if (this._wasOpened)
throw (Components.returnCode = Cr.NS_ERROR_FAILURE);
this._allowPipelining = aAllow;
},
redirectionLimit: 10,
get responseStatus() {
if (this._requestStarted)
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
return this._responseStatus;
},
get responseStatusText() {
if (this._requestStarted)
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
return this._responseText;
},
get requestSucceeded() {
if (this._requestStarted)
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
return this._requestSucceeded;
},
isNoCacheResponse: function Channel_isNoCacheResponse() false,
isNoStoreResponse: function Channel_isNoStoreResponse() false,
getRequestHeader: function Channel_getRequestHeader() {
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
},
setRequestHeader: function Channel_setRequestHeader() {
if (this._wasOpened)
throw (Components.returnCode = Cr.NS_ERROR_IN_PROGRESS);
},
visitRequestHeaders: function Channel_visitRequestHeaders() {},
getResponseHeader: function Channel_getResponseHeader(aHeader) {
let name = aHeader.toLowerCase();
if (name in this._responseHeaders)
return this._responseHeaders[name];
throw (Components.returnCode = Cr.NS_ERROR_NOT_AVAILABLE);
},
setResponseHeader: function Channel_setResponseHeader(aHeader, aValue, aMerge) {
let name = aHeader.toLowerCase();
if (!aValue && !aMerge)
delete this._responseHeaders[name];
else
this._responseHeaders[name] = aValue;
},
visitResponseHeaders: function Channel_visitResponseHeaders(aVisitor) {
for (let name in this._responseHeaders) {
let value = this._responseHeaders[name];
try {
aVisitor.visitHeader(name, value);
} catch (e) {
// The visitor can throw to stop the iteration.
return;
}
}
},
/* :::::::: nsIHttpChannelInternal ::::::::::::::: */
documentURI: null,
get canceled() this._canceled,
allowSpdy: false,
QueryInterface: XPCOMUtils.generateQI([Ci.nsIChannel,
Ci.nsIHttpChannel,
Ci.nsIHttpChannelInternal,
Ci.nsIRequest])
}
/**
* Parses a given URI and extracts all parameters relevant to this protocol.
* @param aURI The URI to parse.
* @return The parsed parameters.
*/
function parseURI(aURI) {
let {scheme, staticHost} = PageThumbs;
let re = new RegExp("^" + scheme + "://" + staticHost + ".*?\\?");
let query = aURI.spec.replace(re, "");
let params = {};
query.split("&").forEach(function (aParam) {
let [key, value] = aParam.split("=").map(decodeURIComponent);
params[key.toLowerCase()] = value;
});
return params;
}