1 files changed, 269 insertions, 0 deletions
diff --git a/toolkit/mozapps/extensions/amWebAPI.js b/toolkit/mozapps/extensions/amWebAPI.js
new file mode 100644
index 000000000..5ad0d23f1
--- /dev/null
+++ b/toolkit/mozapps/extensions/amWebAPI.js
@@ -0,0 +1,269 @@
+/* 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";
+
+const {classes: Cc, interfaces: Ci, utils: Cu, results: Cr} = Components;
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+
+const MSG_PROMISE_REQUEST  = "WebAPIPromiseRequest";
+const MSG_PROMISE_RESULT   = "WebAPIPromiseResult";
+const MSG_INSTALL_EVENT    = "WebAPIInstallEvent";
+const MSG_INSTALL_CLEANUP  = "WebAPICleanup";
+const MSG_ADDON_EVENT_REQ  = "WebAPIAddonEventRequest";
+const MSG_ADDON_EVENT      = "WebAPIAddonEvent";
+
+class APIBroker {
+  constructor(mm) {
+    this.mm = mm;
+
+    this._promises = new Map();
+
+    // _installMap maps integer ids to DOM AddonInstall instances
+    this._installMap = new Map();
+
+    this.mm.addMessageListener(MSG_PROMISE_RESULT, this);
+    this.mm.addMessageListener(MSG_INSTALL_EVENT, this);
+
+    this._eventListener = null;
+  }
+
+  receiveMessage(message) {
+    let payload = message.data;
+
+    switch (message.name) {
+      case MSG_PROMISE_RESULT: {
+        if (!this._promises.has(payload.callbackID)) {
+          return;
+        }
+
+        let resolve = this._promises.get(payload.callbackID);
+        this._promises.delete(payload.callbackID);
+        resolve(payload);
+        break;
+      }
+
+      case MSG_INSTALL_EVENT: {
+        let install = this._installMap.get(payload.id);
+        if (!install) {
+          let err = new Error(`Got install event for unknown install ${payload.id}`);
+          Cu.reportError(err);
+          return;
+        }
+        install._dispatch(payload);
+        break;
+      }
+
+      case MSG_ADDON_EVENT: {
+        if (this._eventListener) {
+          this._eventListener(payload);
+        }
+      }
+    }
+  }
+
+  sendRequest(type, ...args) {
+    return new Promise(resolve => {
+      let callbackID = APIBroker._nextID++;
+
+      this._promises.set(callbackID, resolve);
+      this.mm.sendAsyncMessage(MSG_PROMISE_REQUEST, { type, callbackID, args });
+    });
+  }
+
+  setAddonListener(callback) {
+    this._eventListener = callback;
+    if (callback) {
+      this.mm.addMessageListener(MSG_ADDON_EVENT, this);
+      this.mm.sendAsyncMessage(MSG_ADDON_EVENT_REQ, {enabled: true});
+    } else {
+      this.mm.removeMessageListener(MSG_ADDON_EVENT, this);
+      this.mm.sendAsyncMessage(MSG_ADDON_EVENT_REQ, {enabled: false});
+    }
+  }
+
+  sendCleanup(ids) {
+    this.setAddonListener(null);
+    this.mm.sendAsyncMessage(MSG_INSTALL_CLEANUP, { ids });
+  }
+}
+
+APIBroker._nextID = 0;
+
+// Base class for building classes to back content-exposed interfaces.
+class APIObject {
+  init(window, broker, properties) {
+    this.window = window;
+    this.broker = broker;
+
+    // Copy any provided properties onto this object, webidl bindings
+    // will only expose to content what should be exposed.
+    for (let key of Object.keys(properties)) {
+      this[key] = properties[key];
+    }
+  }
+
+  /**
+   * Helper to implement an asychronous method visible to content, where
+   * the method is implemented by sending a message to the parent process
+   * and then wrapping the returned object or error in an appropriate object.
+   * This helper method ensures that:
+   *  - Returned Promise objects are from the content window
+   *  - Rejected Promises have Error objects from the content window
+   *  - Only non-internal errors are exposed to the caller
+   *
+   * @param {string} apiRequest The command to invoke in the parent process.
+   * @param {array<cloneable>} apiArgs The arguments to include with the
+   *                                   request to the parent process.
+   * @param {function} resultConvert If provided, a function called with the
+   *                                 result from the parent process as an
+   *                                 argument.  Used to convert the result
+   *                                 into something appropriate for content.
+   * @returns {Promise<any>} A Promise suitable for passing directly to content.
+   */
+  _apiTask(apiRequest, apiArgs, resultConverter) {
+    let win = this.window;
+    let broker = this.broker;
+    return new win.Promise((resolve, reject) => {
+      Task.spawn(function*() {
+        let result = yield broker.sendRequest(apiRequest, ...apiArgs);
+        if ("reject" in result) {
+          let err = new win.Error(result.reject.message);
+          // We don't currently put any other properties onto Errors
+          // generated by mozAddonManager.  If/when we do, they will
+          // need to get copied here.
+          reject(err);
+          return;
+        }
+
+        let obj = result.resolve;
+        if (resultConverter) {
+          obj = resultConverter(obj);
+        }
+        resolve(obj);
+      }).catch(err => {
+        Cu.reportError(err);
+        reject(new win.Error("Unexpected internal error"));
+      });
+    });
+  }
+}
+
+class Addon extends APIObject {
+  constructor(...args) {
+    super();
+    this.init(...args);
+  }
+
+  uninstall() {
+    return this._apiTask("addonUninstall", [this.id]);
+  }
+
+  setEnabled(value) {
+    return this._apiTask("addonSetEnabled", [this.id, value]);
+  }
+}
+
+class AddonInstall extends APIObject {
+  constructor(window, broker, properties) {
+    super();
+    this.init(window, broker, properties);
+
+    broker._installMap.set(properties.id, this);
+  }
+
+  _dispatch(data) {
+    // The message for the event includes updated copies of all install
+    // properties.  Use the usual "let webidl filter visible properties" trick.
+    for (let key of Object.keys(data)) {
+      this[key] = data[key];
+    }
+
+    let event = new this.window.Event(data.event);
+    this.__DOM_IMPL__.dispatchEvent(event);
+  }
+
+  install() {
+    return this._apiTask("addonInstallDoInstall", [this.id]);
+  }
+
+  cancel() {
+    return this._apiTask("addonInstallCancel", [this.id]);
+  }
+}
+
+class WebAPI extends APIObject {
+  constructor() {
+    super();
+    this.allInstalls = [];
+    this.listenerCount = 0;
+  }
+
+  init(window) {
+    let mm = window
+        .QueryInterface(Ci.nsIInterfaceRequestor)
+        .getInterface(Ci.nsIDocShell)
+        .QueryInterface(Ci.nsIInterfaceRequestor)
+        .getInterface(Ci.nsIContentFrameMessageManager);
+    let broker = new APIBroker(mm);
+
+    super.init(window, broker, {});
+
+    window.addEventListener("unload", event => {
+      this.broker.sendCleanup(this.allInstalls);
+    });
+  }
+
+  getAddonByID(id) {
+    return this._apiTask("getAddonByID", [id], addonInfo => {
+      if (!addonInfo) {
+        return null;
+      }
+      let addon = new Addon(this.window, this.broker, addonInfo);
+      return this.window.Addon._create(this.window, addon);
+    });
+  }
+
+  createInstall(options) {
+    return this._apiTask("createInstall", [options], installInfo => {
+      if (!installInfo) {
+        return null;
+      }
+      let install = new AddonInstall(this.window, this.broker, installInfo);
+      this.allInstalls.push(installInfo.id);
+      return this.window.AddonInstall._create(this.window, install);
+    });
+  }
+
+  eventListenerWasAdded(type) {
+    if (this.listenerCount == 0) {
+      this.broker.setAddonListener(data => {
+        let event = new this.window.AddonEvent(data.event, data);
+        this.__DOM_IMPL__.dispatchEvent(event);
+      });
+    }
+    this.listenerCount++;
+  }
+
+  eventListenerWasRemoved(type) {
+    this.listenerCount--;
+    if (this.listenerCount == 0) {
+      this.broker.setAddonListener(null);
+    }
+  }
+
+  QueryInterface(iid) {
+    if (iid.equals(WebAPI.classID) || iid.equals(Ci.nsISupports)
+        || iid.equals(Ci.nsIDOMGlobalPropertyInitializer)) {
+      return this;
+    }
+    return Cr.NS_ERROR_NO_INTERFACE;
+  }
+}
+
+WebAPI.prototype.classID = Components.ID("{8866d8e3-4ea5-48b7-a891-13ba0ac15235}");
+this.NSGetFactory = XPCOMUtils.generateNSGetFactory([WebAPI]);