The Tor Browser: toolkit/devtools/server/actors/webapps.js@6474c204b198 (annotated)

toolkit/devtools/server/actors/webapps.js@6474c204b198 (annotated)

toolkit/devtools/server/actors/webapps.js

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* 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/. */
 "use strict";
 let Cu = Components.utils;
 let Cc = Components.classes;
 let Ci = Components.interfaces;
 let CC = Components.Constructor;
 Cu.import("resource://gre/modules/osfile.jsm");
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 let {devtools} = Cu.import("resource://gre/modules/devtools/Loader.jsm", {});
 let promise;
 function debug(aMsg) {
   /*
   Cc["@mozilla.org/consoleservice;1"]
     .getService(Ci.nsIConsoleService)
     .logStringMessage("--*-- WebappsActor : " + aMsg);
   */
 }
 function PackageUploadActor(aPath, aFile) {
   this._path = aPath;
   this._file = aFile;
   this.size = 0;
 }
 PackageUploadActor.prototype = {
   actorPrefix: "packageUploadActor",
   /**
    * This method isn't exposed to the client.
    * It is meant to be called by server code, in order to get
    * access to the temporary file out of the actor ID.
    */
   getFilePath: function () {
     return this._path;
   },
   /**
    * This method allows you to upload a piece of file.
    * It expects a chunk argument that is the a string to write to the file.
    */
   chunk: function (aRequest) {
     let chunk = aRequest.chunk;
     if (!chunk || chunk.length <= 0) {
       return {error: "parameterError",
               message: "Missing or invalid chunk argument"};
     }
     // Translate the string used to transfer the chunk over JSON
     // back to a typed array
     let data = new Uint8Array(chunk.length);
     for (let i = 0, l = chunk.length; i < l ; i++) {
       data[i] = chunk.charCodeAt(i);
     }
     return this._file.write(data)
                .then((written) => {
                  this.size += written;
                  return {
                    written: written,
                    size: this.size
                  };
                });
   },
   /**
    * This method needs to be called, when you are done uploading
    * chunks, before trying to access/use the temporary file.
    * Otherwise, the file may be partially written
    * and also be locked.
    */
   done: function (aRequest) {
     this._file.close();
     return {};
   },
   /**
    * This method allows you to delete the temporary file,
    * when you are done using it.
    */
   remove: function (aRequest) {
     this._cleanupFile();
     return {};
   },
   _cleanupFile: function () {
     try {
       this._file.close();
     } catch(e) {}
     try {
       OS.File.remove(this._path);
     } catch(e) {}
   }
 };
 /**
  * The request types this actor can handle.
  */
 PackageUploadActor.prototype.requestTypes = {
   "chunk": PackageUploadActor.prototype.chunk,
   "done": PackageUploadActor.prototype.done,
   "remove": PackageUploadActor.prototype.remove
 };
 /**
  * Creates a WebappsActor. WebappsActor provides remote access to
  * install apps.
  */
 function WebappsActor(aConnection) {
   debug("init");
   // Load actor dependencies lazily as this actor require extra environnement
   // preparation to work (like have a profile setup in xpcshell tests)
   Cu.import("resource://gre/modules/Webapps.jsm");
   Cu.import("resource://gre/modules/AppsUtils.jsm");
   Cu.import("resource://gre/modules/FileUtils.jsm");
   // Keep reference of already created app actors.
   // key: app frame message manager, value: ContentActor's grip() value
   this._appActorsMap = new Map();
   this.conn = aConnection;
   this._uploads = [];
   this._actorPool = new ActorPool(this.conn);
   this.conn.addActorPool(this._actorPool);
 }
 WebappsActor.prototype = {
   actorPrefix: "webapps",
   disconnect: function () {
     // When we stop using this actor, we should ensure removing all files.
     for (let upload of this._uploads) {
       upload.remove();
     }
     this._uploads = null;
     this.conn.removeActorPool(this._actorPool);
     this._actorPool = null;
     this.conn = null;
   },
   _registerApp: function wa_actorRegisterApp(aDeferred, aApp, aId, aDir) {
     debug("registerApp");
     let reg = DOMApplicationRegistry;
     let self = this;
     // Clean up the deprecated manifest cache if needed.
     if (aId in reg._manifestCache) {
       delete reg._manifestCache[aId];
     }
     aApp.installTime = Date.now();
     aApp.installState = "installed";
     aApp.removable = true;
     aApp.id = aId;
     aApp.basePath = reg.getWebAppsBasePath();
     aApp.localId = (aId in reg.webapps) ? reg.webapps[aId].localId
                                         : reg._nextLocalId();
     reg.webapps[aId] = aApp;
     reg.updatePermissionsForApp(aId);
     reg._readManifests([{ id: aId }]).then((aResult) => {
       let manifest = aResult[0].manifest;
       aApp.name = manifest.name;
       reg.updateAppHandlers(null, manifest, aApp);
       reg._saveApps().then(() => {
         aApp.manifest = manifest;
         // Needed to evict manifest cache on content side
         // (has to be dispatched first, otherwise other messages like
         // Install:Return:OK are going to use old manifest version)
         reg.broadcastMessage("Webapps:UpdateState", {
           app: aApp,
           manifest: manifest,
           manifestURL: aApp.manifestURL
         });
         reg.broadcastMessage("Webapps:FireEvent", {
           eventType: ["downloadsuccess", "downloadapplied"],
           manifestURL: aApp.manifestURL
         });
         reg.broadcastMessage("Webapps:AddApp", { id: aId, app: aApp });
         reg.broadcastMessage("Webapps:Install:Return:OK", {
           app: aApp,
           oid: "foo",
           requestID: "bar"
         });
         Services.obs.notifyObservers(null, "webapps-installed",
           JSON.stringify({ manifestURL: aApp.manifestURL }));
         delete aApp.manifest;
         aDeferred.resolve({ appId: aId, path: aDir.path });
         // We can't have appcache for packaged apps.
         if (!aApp.origin.startsWith("app://")) {
           reg.startOfflineCacheDownload(new ManifestHelper(manifest, aApp.origin));
         }
       });
       // Cleanup by removing the temporary directory.
       if (aDir.exists())
         aDir.remove(true);
     });
   },
   _sendError: function wa_actorSendError(aDeferred, aMsg, aId) {
     debug("Sending error: " + aMsg);
     aDeferred.resolve({
       error: "installationFailed",
       message: aMsg,
       appId: aId
     });
   },
   _getAppType: function wa_actorGetAppType(aType) {
     let type = Ci.nsIPrincipal.APP_STATUS_INSTALLED;
     if (aType) {
       type = aType == "privileged" ? Ci.nsIPrincipal.APP_STATUS_PRIVILEGED
            : aType == "certified" ? Ci.nsIPrincipal.APP_STATUS_CERTIFIED
            : Ci.nsIPrincipal.APP_STATUS_INSTALLED;
     }
     return type;
   },
   uploadPackage: function () {
     debug("uploadPackage\n");
     let tmpDir = FileUtils.getDir("TmpD", ["file-upload"], true, false);
     if (!tmpDir.exists() || !tmpDir.isDirectory()) {
       return {error: "fileAccessError",
               message: "Unable to create temporary folder"};
     }
     let tmpFile = tmpDir;
     tmpFile.append("package.zip");
     tmpFile.createUnique(Ci.nsIFile.NORMAL_FILE_TYPE, parseInt("0666", 8));
     if (!tmpFile.exists() || !tmpDir.isFile()) {
       return {error: "fileAccessError",
               message: "Unable to create temporary file"};
     }
     return OS.File.open(tmpFile.path, { write: true, truncate: true })
              .then((file) => {
                 let actor = new PackageUploadActor(tmpFile.path, file);
                 this._actorPool.addActor(actor);
                 this._uploads.push(actor);
                 return { actor: actor.actorID };
              });
   },
   installHostedApp: function wa_actorInstallHosted(aDir, aId, aReceipts,
                                                    aManifest, aMetadata) {
     debug("installHostedApp");
     let self = this;
     let deferred = promise.defer();
     function readManifest() {
       if (aManifest) {
         return promise.resolve(aManifest);
       } else {
         let manFile = OS.Path.join(aDir.path, "manifest.webapp");
         return AppsUtils.loadJSONAsync(manFile);
       }
     }
     function checkSideloading(aManifest) {
       return self._getAppType(aManifest.type);
     }
     function writeManifest(aAppType) {
       // Move manifest.webapp to the destination directory.
       // The destination directory for this app.
       let installDir = DOMApplicationRegistry._getAppDir(aId);
       if (aManifest) {
         let manFile = OS.Path.join(installDir.path, "manifest.webapp");
         return DOMApplicationRegistry._writeFile(manFile, JSON.stringify(aManifest)).then(() => {
           return aAppType;
         });
       } else {
         let manFile = aDir.clone();
         manFile.append("manifest.webapp");
         manFile.moveTo(installDir, "manifest.webapp");
       }
       return null;
     }
     function readMetadata(aAppType) {
       if (aMetadata) {
         return { metadata: aMetadata, appType: aAppType };
       }
       // Read the origin and manifest url from metadata.json
       let metaFile = OS.Path.join(aDir.path, "metadata.json");
       return AppsUtils.loadJSONAsync(metaFile).then((aMetadata) => {
         if (!aMetadata) {
           throw("Error parsing metadata.json.");
         }
         if (!aMetadata.origin) {
           throw("Missing 'origin' property in metadata.json");
         }
         return { metadata: aMetadata, appType: aAppType };
       });
     }
     let runnable = {
       run: function run() {
         try {
           readManifest().
             then(writeManifest).
             then(checkSideloading).
             then(readMetadata).
             then(function ({ metadata, appType }) {
               let origin = metadata.origin;
               let manifestURL = metadata.manifestURL ||
                                 origin + "/manifest.webapp";
               // Create a fake app object with the minimum set of properties we need.
               let app = {
                 origin: origin,
                 installOrigin: metadata.installOrigin || origin,
                 manifestURL: manifestURL,
                 appStatus: appType,
                 receipts: aReceipts,
               };
               self._registerApp(deferred, app, aId, aDir);
             }, function (error) {
               self._sendError(deferred, error, aId);
             });
         } catch(e) {
           // If anything goes wrong, just send it back.
           self._sendError(deferred, e.toString(), aId);
         }
       }
     }
     Services.tm.currentThread.dispatch(runnable,
                                        Ci.nsIThread.DISPATCH_NORMAL);
     return deferred.promise;
   },
   installPackagedApp: function wa_actorInstallPackaged(aDir, aId, aReceipts) {
     debug("installPackagedApp");
     let self = this;
     let deferred = promise.defer();
     let runnable = {
       run: function run() {
         try {
           // Open the app zip package
           let zipFile = aDir.clone();
           zipFile.append("application.zip");
           let zipReader = Cc["@mozilla.org/libjar/zip-reader;1"]
                             .createInstance(Ci.nsIZipReader);
           zipReader.open(zipFile);
           // Read app manifest `manifest.webapp` from `application.zip`
           let istream = zipReader.getInputStream("manifest.webapp");
           let converter = Cc["@mozilla.org/intl/scriptableunicodeconverter"]
                             .createInstance(Ci.nsIScriptableUnicodeConverter);
           converter.charset = "UTF-8";
           let jsonString = converter.ConvertToUnicode(
             NetUtil.readInputStreamToString(istream, istream.available())
           );
           let manifest;
           try {
             manifest = JSON.parse(jsonString);
           } catch(e) {
             self._sendError(deferred, "Error Parsing manifest.webapp: " + e, aId);
           }
           let appType = self._getAppType(manifest.type);
           // Privileged and certified packaged apps can setup a custom origin
           // via `origin` manifest property
           let id = aId;
           if (appType >= Ci.nsIPrincipal.APP_STATUS_PRIVILEGED &&
               manifest.origin !== undefined) {
             let uri;
             try {
               uri = Services.io.newURI(manifest.origin, null, null);
             } catch(e) {
               self._sendError(deferred, "Invalid origin in webapp's manifest", aId);
             }
             if (uri.scheme != "app") {
               self._sendError(deferred, "Invalid origin in webapp's manifest", aId);
             }
             id = uri.prePath.substring(6);
           }
           // Only after security checks are made and after final app id is computed
           // we can move application.zip to the destination directory, and
           // extract manifest.webapp there.
           let installDir = DOMApplicationRegistry._getAppDir(id);
           let manFile = installDir.clone();
           manFile.append("manifest.webapp");
           zipReader.extract("manifest.webapp", manFile);
           zipReader.close();
           zipFile.moveTo(installDir, "application.zip");
           let origin = "app://" + id;
           let manifestURL = origin + "/manifest.webapp";
           // Refresh application.zip content (e.g. reinstall app), as done here:
           // http://hg.mozilla.org/mozilla-central/annotate/aaefec5d34f8/dom/apps/src/Webapps.jsm#l1125
           // Do it in parent process for the simulator
           let jar = installDir.clone();
           jar.append("application.zip");
           Services.obs.notifyObservers(jar, "flush-cache-entry", null);
           // And then in app content process
           // This function will be evaluated in the scope of the content process
           // frame script. That will flush the jar cache for this app and allow
           // loading fresh updated resources if we reload its document.
           let FlushFrameScript = function (path) {
             let jar = Components.classes["@mozilla.org/file/local;1"]
                                 .createInstance(Components.interfaces.nsILocalFile);
             jar.initWithPath(path);
             let obs = Components.classes["@mozilla.org/observer-service;1"]
                                 .getService(Components.interfaces.nsIObserverService);
             obs.notifyObservers(jar, "flush-cache-entry", null);
           };
           for each (let frame in self._appFrames()) {
             if (frame.getAttribute("mozapp") == manifestURL) {
               let mm = frame.QueryInterface(Ci.nsIFrameLoaderOwner).frameLoader.messageManager;
               mm.loadFrameScript("data:," +
                 encodeURIComponent("(" + FlushFrameScript.toString() + ")" +
                                    "('" + jar.path + "')"), false);
             }
           }
           // Create a fake app object with the minimum set of properties we need.
           let app = {
             origin: origin,
             installOrigin: origin,
             manifestURL: manifestURL,
             appStatus: appType,
             receipts: aReceipts,
           }
           self._registerApp(deferred, app, id, aDir);
         } catch(e) {
           // If anything goes wrong, just send it back.
           self._sendError(deferred, e.toString(), aId);
         }
       }
     }
     Services.tm.currentThread.dispatch(runnable,
                                        Ci.nsIThread.DISPATCH_NORMAL);
     return deferred.promise;
   },
   /**
     * @param appId   : The id of the app we want to install. We will look for
     *                  the files for the app in $TMP/b2g/$appId :
     *                  For packaged apps: application.zip
     *                  For hosted apps:   metadata.json and manifest.webapp
     */
   install: function wa_actorInstall(aRequest) {
     debug("install");
     let appId = aRequest.appId;
     let reg = DOMApplicationRegistry;
     if (!appId) {
       appId = reg.makeAppId();
     }
     // Check that we are not overriding a preinstalled application.
     if (appId in reg.webapps && reg.webapps[appId].removable === false) {
       return { error: "badParameterType",
                message: "The application " + appId + " can't be overriden."
              }
     }
     let appDir = FileUtils.getDir("TmpD", ["b2g", appId], false, false);
     if (aRequest.upload) {
       // Ensure creating the directory (recursively)
       appDir = FileUtils.getDir("TmpD", ["b2g", appId], true, false);
       let actor = this.conn.getActor(aRequest.upload);
       if (!actor) {
         return { error: "badParameter",
                  message: "Unable to find upload actor '" + aRequest.upload
                           + "'" };
       }
       let appFile = FileUtils.File(actor.getFilePath());
       if (!appFile.exists()) {
         return { error: "badParameter",
                  message: "The uploaded file doesn't exist on device" };
       }
       appFile.moveTo(appDir, "application.zip");
     } else if ((!appDir || !appDir.exists()) &&
                !aRequest.manifest && !aRequest.metadata) {
       return { error: "badParameterType",
                message: "missing directory " + appDir.path
              };
     }
     let testFile = appDir.clone();
     testFile.append("application.zip");
     let receipts = (aRequest.receipts && Array.isArray(aRequest.receipts))
                     ? aRequest.receipts
                     : [];
     if (testFile.exists()) {
       return this.installPackagedApp(appDir, appId, receipts);
     }
     let manifest, metadata;
     let missing =
       ["manifest.webapp", "metadata.json"]
       .some(function(aName) {
         testFile = appDir.clone();
         testFile.append(aName);
         return !testFile.exists();
       });
     if (missing) {
       if (aRequest.manifest && aRequest.metadata &&
           aRequest.metadata.origin) {
         manifest = aRequest.manifest;
         metadata = aRequest.metadata;
       } else {
         try {
           appDir.remove(true);
         } catch(e) {}
         return { error: "badParameterType",
                  message: "hosted app file and manifest/metadata fields " +
                           "are missing"
         };
       }
     }
     return this.installHostedApp(appDir, appId, receipts, manifest, metadata);
   },
   getAll: function wa_actorGetAll(aRequest) {
     debug("getAll");
     let deferred = promise.defer();
     let reg = DOMApplicationRegistry;
     reg.getAll(apps => {
       deferred.resolve({ apps: this._filterAllowedApps(apps) });
     });
     return deferred.promise;
   },
   getApp: function wa_actorGetApp(aRequest) {
     debug("getApp");
     let manifestURL = aRequest.manifestURL;
     if (!manifestURL) {
       return { error: "missingParameter",
                message: "missing parameter manifestURL" };
     }
     let reg = DOMApplicationRegistry;
     let app = reg.getAppByManifestURL(manifestURL);
     if (!app) {
       return { error: "appNotFound" };
     }
     return this._isAppAllowedForURL(app.manifestURL).then(allowed => {
       if (!allowed) {
         return { error: "forbidden" };
       }
       return reg.getManifestFor(manifestURL).then(function (manifest) {
         app.manifest = manifest;
         return { app: app };
       });
     });
   },
   _areCertifiedAppsAllowed: function wa__areCertifiedAppsAllowed() {
     let pref = "devtools.debugger.forbid-certified-apps";
     return !Services.prefs.getBoolPref(pref);
   },
   _isAppAllowedForManifest: function wa__isAppAllowedForManifest(aManifest) {
     if (this._areCertifiedAppsAllowed()) {
       return true;
     }
     let type = this._getAppType(aManifest.type);
     return type !== Ci.nsIPrincipal.APP_STATUS_CERTIFIED;
   },
   _filterAllowedApps: function wa__filterAllowedApps(aApps) {
     return aApps.filter(app => this._isAppAllowedForManifest(app.manifest));
   },
   _isAppAllowedForURL: function wa__isAppAllowedForURL(aManifestURL) {
     return this._findManifestByURL(aManifestURL).then(manifest => {
       return this._isAppAllowedForManifest(manifest);
     });
   },
   uninstall: function wa_actorUninstall(aRequest) {
     debug("uninstall");
     let manifestURL = aRequest.manifestURL;
     if (!manifestURL) {
       return { error: "missingParameter",
                message: "missing parameter manifestURL" };
     }
     let deferred = promise.defer();
     let reg = DOMApplicationRegistry;
     reg.uninstall(
       manifestURL,
       function onsuccess() {
         deferred.resolve({});
       },
       function onfailure(reason) {
         deferred.resolve({ error: reason });
       }
     );
     return deferred.promise;
   },
   _findManifestByURL: function wa__findManifestByURL(aManifestURL) {
     let deferred = promise.defer();
     let reg = DOMApplicationRegistry;
     let id = reg._appIdForManifestURL(aManifestURL);
     reg._readManifests([{ id: id }]).then((aResults) => {
       deferred.resolve(aResults[0].manifest);
     });
     return deferred.promise;
   },
   getIconAsDataURL: function (aRequest) {
     debug("getIconAsDataURL");
     let manifestURL = aRequest.manifestURL;
     if (!manifestURL) {
       return { error: "missingParameter",
                message: "missing parameter manifestURL" };
     }
     let reg = DOMApplicationRegistry;
     let app = reg.getAppByManifestURL(manifestURL);
     if (!app) {
       return { error: "wrongParameter",
                message: "No application for " + manifestURL };
     }
     let deferred = promise.defer();
     this._findManifestByURL(manifestURL).then(jsonManifest => {
       let manifest = new ManifestHelper(jsonManifest, app.origin);
       let iconURL = manifest.iconURLForSize(aRequest.size || 128);
       if (!iconURL) {
         deferred.resolve({
           error: "noIcon",
           message: "This app has no icon"
         });
         return;
       }
       // Download the URL as a blob
       // bug 899177: there is a bug with xhr and app:// and jar:// uris
       // that ends up forcing the content type to application/xml.
       let req = Cc['@mozilla.org/xmlextras/xmlhttprequest;1']
                   .createInstance(Ci.nsIXMLHttpRequest);
       req.open("GET", iconURL, false);
       req.responseType = "blob";
       try {
         req.send(null);
       } catch(e) {
         deferred.resolve({
           error: "noIcon",
           message: "The icon file '" + iconURL + "' doesn't exist"
         });
         return;
       }
       // Convert the blog to a base64 encoded data URI
       let reader = Cc["@mozilla.org/files/filereader;1"]
                      .createInstance(Ci.nsIDOMFileReader);
       reader.onload = function () {
         deferred.resolve({
           url: reader.result
         });
       };
       reader.onerror = function () {
         deferred.resolve({
           error: reader.error.name,
           message: String(reader.error)
         });
       };
       reader.readAsDataURL(req.response);
     });
     return deferred.promise;
   },
   launch: function wa_actorLaunch(aRequest) {
     debug("launch");
     let manifestURL = aRequest.manifestURL;
     if (!manifestURL) {
       return { error: "missingParameter",
                message: "missing parameter manifestURL" };
     }
     let deferred = promise.defer();
     DOMApplicationRegistry.launch(
       aRequest.manifestURL,
       aRequest.startPoint || "",
       Date.now(),
       function onsuccess() {
         deferred.resolve({});
       },
       function onfailure(reason) {
         deferred.resolve({ error: reason });
       });
     return deferred.promise;
   },
   close: function wa_actorLaunch(aRequest) {
     debug("close");
     let manifestURL = aRequest.manifestURL;
     if (!manifestURL) {
       return { error: "missingParameter",
                message: "missing parameter manifestURL" };
     }
     let reg = DOMApplicationRegistry;
     let app = reg.getAppByManifestURL(manifestURL);
     if (!app) {
       return { error: "missingParameter",
                message: "No application for " + manifestURL };
     }
     reg.close(app);
     return {};
   },
   _appFrames: function () {
     // For now, we only support app frames on b2g
     if (Services.appinfo.ID != "{3c2e2abc-06d4-11e1-ac3b-374f68613e61}") {
       return;
     }
     // Register the system app
     let chromeWindow = Services.wm.getMostRecentWindow('navigator:browser');
     let systemAppFrame = chromeWindow.shell.contentBrowser;
     yield systemAppFrame;
     // Register apps hosted in the system app. i.e. the homescreen, all regular
     // apps and the keyboard.
     // Bookmark apps and other system app internal frames like captive portal
     // are also hosted in system app, but they are not using mozapp attribute.
     let frames = systemAppFrame.contentDocument.querySelectorAll("iframe[mozapp]");
     for (let i = 0; i < frames.length; i++) {
       yield frames[i];
     }
   },
   listRunningApps: function (aRequest) {
     debug("listRunningApps\n");
     let appPromises = [];
     let apps = [];
     for each (let frame in this._appFrames()) {
       let manifestURL = frame.getAttribute("mozapp");
       appPromises.push(this._isAppAllowedForURL(manifestURL).then(allowed => {
         if (allowed) {
           apps.push(manifestURL);
         }
       }));
     }
     return promise.all(appPromises).then(() => {
       return { apps: apps };
     });
   },
   getAppActor: function ({ manifestURL }) {
     debug("getAppActor\n");
     let appFrame = null;
     for each (let frame in this._appFrames()) {
       if (frame.getAttribute("mozapp") == manifestURL) {
         appFrame = frame;
         break;
       }
     }
     let notFoundError = {
       error: "appNotFound",
       message: "Unable to find any opened app whose manifest " +
                "is '" + manifestURL + "'"
     };
     if (!appFrame) {
       return notFoundError;
     }
     return this._isAppAllowedForURL(manifestURL).then(allowed => {
       if (!allowed) {
         return notFoundError;
       }
       // Only create a new actor, if we haven't already
       // instanciated one for this connection.
       let map = this._appActorsMap;
       let mm = appFrame.QueryInterface(Ci.nsIFrameLoaderOwner)
                        .frameLoader
                        .messageManager;
       let actor = map.get(mm);
       if (!actor) {
         let onConnect = actor => {
           map.set(mm, actor);
           return { actor: actor };
         };
         let onDisconnect = mm => {
           map.delete(mm);
         };
         return DebuggerServer.connectToChild(this.conn, appFrame, onDisconnect)
                              .then(onConnect);
       }
       return { actor: actor };
     });
   },
   watchApps: function () {
     this._openedApps = new Set();
     // For now, app open/close events are only implement on b2g
     if (Services.appinfo.ID == "{3c2e2abc-06d4-11e1-ac3b-374f68613e61}") {
       let chromeWindow = Services.wm.getMostRecentWindow('navigator:browser');
       let systemAppFrame = chromeWindow.getContentWindow();
       systemAppFrame.addEventListener("appwillopen", this);
       systemAppFrame.addEventListener("appterminated", this);
     }
     Services.obs.addObserver(this, "webapps-installed", false);
     Services.obs.addObserver(this, "webapps-uninstall", false);
     return {};
   },
   unwatchApps: function () {
     this._openedApps = null;
     if (Services.appinfo.ID == "{3c2e2abc-06d4-11e1-ac3b-374f68613e61}") {
       let chromeWindow = Services.wm.getMostRecentWindow('navigator:browser');
       let systemAppFrame = chromeWindow.getContentWindow();
       systemAppFrame.removeEventListener("appwillopen", this);
       systemAppFrame.removeEventListener("appterminated", this);
     }
     Services.obs.removeObserver(this, "webapps-installed", false);
     Services.obs.removeObserver(this, "webapps-uninstall", false);
     return {};
   },
   handleEvent: function (event) {
     let manifestURL;
     switch(event.type) {
       case "appwillopen":
         manifestURL = event.detail.manifestURL;
         // Ignore the event if we already received an appwillopen for this app
         // (appwillopen is also fired when the app has been moved to background
         // and get back to foreground)
         if (this._openedApps.has(manifestURL)) {
           return;
         }
         this._openedApps.add(manifestURL);
         this._isAppAllowedForURL(manifestURL).then(allowed => {
           if (allowed) {
             this.conn.send({ from: this.actorID,
                              type: "appOpen",
                              manifestURL: manifestURL
                            });
           }
         });
         break;
       case "appterminated":
         manifestURL = event.detail.manifestURL;
         this._openedApps.delete(manifestURL);
         this._isAppAllowedForURL(manifestURL).then(allowed => {
           if (allowed) {
             this.conn.send({ from: this.actorID,
                              type: "appClose",
                              manifestURL: manifestURL
                            });
           }
         });
         break;
     }
   },
   observe: function (subject, topic, data) {
     let app = JSON.parse(data);
     if (topic == "webapps-installed") {
       this.conn.send({ from: this.actorID,
                        type: "appInstall",
                        manifestURL: app.manifestURL
                      });
     } else if (topic == "webapps-uninstall") {
       this.conn.send({ from: this.actorID,
                        type: "appUninstall",
                        manifestURL: app.manifestURL
                      });
     }
   }
 };
 /**
  * The request types this actor can handle.
  */
 WebappsActor.prototype.requestTypes = {
   "install": WebappsActor.prototype.install,
   "uploadPackage": WebappsActor.prototype.uploadPackage,
   "getAll": WebappsActor.prototype.getAll,
   "getApp": WebappsActor.prototype.getApp,
   "launch": WebappsActor.prototype.launch,
   "close": WebappsActor.prototype.close,
   "uninstall": WebappsActor.prototype.uninstall,
   "listRunningApps": WebappsActor.prototype.listRunningApps,
   "getAppActor": WebappsActor.prototype.getAppActor,
   "watchApps": WebappsActor.prototype.watchApps,
   "unwatchApps": WebappsActor.prototype.unwatchApps,
   "getIconAsDataURL": WebappsActor.prototype.getIconAsDataURL
 };
 DebuggerServer.addGlobalActor(WebappsActor, "webappsActor");