gecko-dev/toolkit/components/thumbnails/PageThumbsProtocol.js

113 lines
3.2 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://gre/modules/PageThumbs.jsm");
Cu.import("resource://gre/modules/XPCOMUtils.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "Services",
"resource://gre/modules/Services.jsm");
XPCOMUtils.defineLazyModuleGetter(this, "FileUtils",
"resource://gre/modules/FileUtils.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.getFilePathForURL(url);
let fileuri = Services.io.newFileURI(new FileUtils.File(file));
return Services.io.newChannelFromURI(fileuri);
},
/**
* 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])
};
this.NSGetFactory = XPCOMUtils.generateNSGetFactory([Protocol]);
/**
* 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;
}