Make encryption asynchronous

We're going to need to send out a load of messages to distribute the megolm
keys; as a first step, deal with the asynchronicity this will require.

lib/client.js

@@ -822,10 +822,18 @@ function _sendEvent(client, room, event, callback) {
     // so that we can handle synchronous and asynchronous exceptions with the
     // same code path.
     return q().then(function() {
+        var encryptionPromise = null;
         if (client._crypto) {
-            client._crypto.encryptEventIfNeeded(event, room);
+            encryptionPromise = client._crypto.encryptEventIfNeeded(event, room);
         }
-
+        if (encryptionPromise) {
+            _updatePendingEventStatus(room, event, EventStatus.ENCRYPTING);
+            encryptionPromise = encryptionPromise.then(function() {
+                _updatePendingEventStatus(room, event, EventStatus.SENDING);
+            });
+        }
+        return encryptionPromise;
+    }).then(function() {
         var promise;
         // this event may be queued
         if (client.scheduler) {
@@ -857,11 +865,15 @@ function _sendEvent(client, room, event, callback) {
         // the request failed to send.
         console.error("Error sending event", err.stack || err);
 
+        try {
             _updatePendingEventStatus(room, event, EventStatus.NOT_SENT);
 
             if (callback) {
                 callback(err);
             }
+        } catch (err2) {
+            console.error("Exception in error handler!", err2.stack || err);
+        }
         throw err;
     });
 }

lib/crypto-algorithms/base.js

@@ -20,6 +20,7 @@ limitations under the License.
  *
  * @module crypto-algorithms/base
  */
+var q = require("q");
 
 var utils = require("../utils");
 
@@ -43,6 +44,7 @@ module.exports.DECRYPTION_CLASSES = {};
  * base type for encryption implementations
  *
  * @constructor
+ * @alias module:crypto-algorithms/base.EncryptionAlgorithm
  *
  * @param {object} params parameters
  * @param {string} params.deviceId The identifier for this device.
@@ -50,22 +52,28 @@ module.exports.DECRYPTION_CLASSES = {};
  * @param {module:OlmDevice} params.olmDevice olm.js wrapper
  * @param {string} params.roomId  The ID of the room we will be sending to
  */
-module.exports.EncryptionAlgorithm = function(params) {
+var EncryptionAlgorithm = function(params) {
     this._deviceId = params.deviceId;
     this._crypto = params.crypto;
     this._olmDevice = params.olmDevice;
     this._roomId = params.roomId;
 };
+/** */
+module.exports.EncryptionAlgorithm = EncryptionAlgorithm;
 
 /**
- * Initialise this EncryptionAlgorithm instance for a particular room
+ * Initialise this EncryptionAlgorithm instance for a particular room.
  *
- * @method module:crypto-algorithms/base.EncryptionAlgorithm#initRoomEncryption
+ * <p>This will be called once per EncryptionAlgorithm, just after the
- * @abstract
+ * constructor is called.
  *
  * @param {string[]} roomMembers list of currently-joined users in the room
  * @return {module:client.Promise} Promise which resolves when setup is complete
  */
+EncryptionAlgorithm.prototype.initRoomEncryption = function(roomMembers) {
+    return q();
+};
+
 
 /**
  * Encrypt a message event
@@ -77,7 +85,7 @@ module.exports.EncryptionAlgorithm = function(params) {
  * @param {string} eventType
  * @param {object} plaintext event content
  *
- * @return {object} new event body
+ * @return {module:client.Promise} Promise which resolves to the new event body
  */
 
 

lib/crypto-algorithms/megolm.js

@@ -39,35 +39,33 @@ var MEGOLM_ALGORITHM = "m.megolm.v1.aes-sha2";
  */
 function MegolmEncryption(params) {
     base.EncryptionAlgorithm.call(this, params);
+    this._prepPromise = null;
     this._outboundSessionId = null;
 }
 utils.inherits(MegolmEncryption, base.EncryptionAlgorithm);
 
-/**
- * @inheritdoc
- * @param {string[]} roomMembers list of currently-joined users in the room
- * @return {module:client.Promise} Promise which resolves when setup is complete
- */
-MegolmEncryption.prototype.initRoomEncryption = function(roomMembers) {
-    // nothing to do here.
-    return q();
-};
-
-
 /**
  * @private
+ *
+ * @return {module:client.Promise} Promise which resolves when setup is
+ *   complete.
  */
 MegolmEncryption.prototype._ensureOutboundSession = function() {
-    if (this._outboundSessionId) {
+    if (this._prepPromise) {
-        return;
+        // prep already in progress
+        return this._prepPromise;
     }
+
+    if (this._outboundSessionId) {
+        // prep already done
+        return q();
+    }
+
     var session_id = this._olmDevice.createOutboundGroupSession();
     this._outboundSessionId = session_id;
 
     var key = this._olmDevice.getOutboundGroupSessionKey(session_id);
 
-    // TODO: initiate key-sharing
-
     console.log(
         'Created outbound session. Add with window.mxMatrixClientPeg.' +
             'matrixClient._crypto._olmDevice.addInboundGroupSession("' +
@@ -82,8 +80,17 @@ MegolmEncryption.prototype._ensureOutboundSession = function() {
         this._roomId, this._olmDevice.deviceCurve25519Key, session_id,
         key.key, key.chain_index
     );
+
+    var self = this;
+    // TODO: initiate key-sharing
+    this._prepPromise = q.delay(3000).then(function() {
+        console.log("woop woop, we totally shared the keys");
+        self._prepPromise = null;
+    });
+    return this._prepPromise;
 };
 
+
 /**
  * @inheritdoc
  *
@@ -91,30 +98,31 @@ MegolmEncryption.prototype._ensureOutboundSession = function() {
  * @param {string} eventType
  * @param {object} plaintext event content
  *
- * @return {object} new event body
+ * @return {module:client.Promise} Promise which resolves to the new event body
  */
 MegolmEncryption.prototype.encryptMessage = function(room, eventType, content) {
-    this._ensureOutboundSession();
+    var self = this;
-
+    return this._ensureOutboundSession().then(function() {
         var payloadJson = {
-        room_id: this._roomId,
+            room_id: self._roomId,
             type: eventType,
             content: content
         };
 
-    var ciphertext = this._olmDevice.encryptGroupMessage(
+        var ciphertext = self._olmDevice.encryptGroupMessage(
-        this._outboundSessionId, JSON.stringify(payloadJson)
+            self._outboundSessionId, JSON.stringify(payloadJson)
         );
 
         var encryptedContent = {
             algorithm: MEGOLM_ALGORITHM,
-        sender_key: this._olmDevice.deviceCurve25519Key,
+            sender_key: self._olmDevice.deviceCurve25519Key,
             body: ciphertext,
-        session_id: this._outboundSessionId,
+            session_id: self._outboundSessionId,
             signature: "FIXME",
         };
 
         return encryptedContent;
+    });
 };
 
 /**

lib/crypto-algorithms/olm.js

@@ -20,6 +20,7 @@ limitations under the License.
  *
  * @module crypto-algorithms/olm
  */
+var q = require('q');
 
 var utils = require("../utils");
 
@@ -60,7 +61,7 @@ OlmEncryption.prototype.initRoomEncryption = function(roomMembers) {
  * @param {string} eventType
  * @param {object} plaintext event content
  *
- * @return {object} new event body
+ * @return {module:client.Promise} Promise which resolves to the new event body
  */
 OlmEncryption.prototype.encryptMessage = function(room, eventType, content) {
     if (!room) {
@@ -128,7 +129,7 @@ OlmEncryption.prototype.encryptMessage = function(room, eventType, content) {
         sender_key: this._olmDevice.deviceCurve25519Key,
         ciphertext: ciphertext
     };
-    return encryptedContent;
+    return q(encryptedContent);
 };
 
 /**

lib/crypto.js

@@ -600,7 +600,7 @@ Crypto.prototype.isSenderKeyVerified = function(userId, algorithm, sender_key) {
  * @param {object} config The encryption config for the room.
  * @param {string[]} roomMembers userIds of room members to start sessions with
  *
- * @return {Object} A promise that will resolve when encryption is setup.
+ * @return {module:client.Promise} A promise that will resolve when encryption is setup.
  */
 Crypto.prototype.setRoomEncryption = function(roomId, config, roomMembers) {
     // if we already have encryption in this room, we should ignore this event
@@ -727,18 +727,21 @@ Crypto.prototype.isRoomEncrypted = function(roomId) {
  *
  * @param {module:models/room?} room destination room. Null if the destination
  *     is not a room we have seen over the sync pipe.
+ *
+ * @return {module:client.Promise?} Promise which resolves when the event has been
+ *     encrypted, or null if nothing was needed
  */
 Crypto.prototype.encryptEventIfNeeded = function(event, room) {
     if (event.isEncrypted()) {
         // this event has already been encrypted; this happens if the
         // encryption step succeeded, but the send step failed on the first
         // attempt.
-        return;
+        return null;
     }
 
     if (event.getType() !== "m.room.message") {
         // we only encrypt m.room.message
-        return;
+        return null;
     }
 
     var roomId = event.getRoomId();
@@ -755,13 +758,14 @@ Crypto.prototype.encryptEventIfNeeded = function(event, room) {
                 "configuration event."
             );
         }
-        return;
+        return null;
     }
 
-    var encryptedContent = alg.encryptMessage(
+    return alg.encryptMessage(
         room, event.getType(), event.getContent()
-    );
+    ).then(function(encryptedContent) {
         event.makeEncrypted("m.room.encrypted", encryptedContent);
+    });
 };
 
 /**

lib/models/event.js

@@ -29,6 +29,10 @@ limitations under the License.
 module.exports.EventStatus = {
     /** The event was not sent and will no longer be retried. */
     NOT_SENT: "not_sent",
+
+    /** The message is being encrypted */
+    ENCRYPTING: "encrypting",
+
     /** The event is in the process of being sent. */
     SENDING: "sending",
     /** The event is in a queue waiting to be sent. */

lib/models/room.js

@@ -845,8 +845,17 @@ Room.prototype._handleRemoteEcho = function(remoteEvent, localEvent) {
  */
 var ALLOWED_TRANSITIONS = {};
 
-ALLOWED_TRANSITIONS[EventStatus.SENDING] =
+ALLOWED_TRANSITIONS[EventStatus.ENCRYPTING] = [
-    [EventStatus.QUEUED, EventStatus.NOT_SENT, EventStatus.SENT];
+    EventStatus.SENDING,
+    EventStatus.NOT_SENT,
+];
+
+ALLOWED_TRANSITIONS[EventStatus.SENDING] = [
+    EventStatus.ENCRYPTING,
+    EventStatus.QUEUED,
+    EventStatus.NOT_SENT,
+    EventStatus.SENT,
+];
 
 ALLOWED_TRANSITIONS[EventStatus.QUEUED] =
     [EventStatus.SENDING, EventStatus.CANCELLED];

spec/integ/matrix-client-retrying.spec.js

@@ -1,5 +1,4 @@
 "use strict";
-var q = require("q");
 var sdk = require("../..");
 var HttpBackend = require("../mock-request");
 var utils = require("../test-utils");
@@ -69,8 +68,8 @@ describe("MatrixClient retrying", function() {
         expect(ev1.status).toEqual(EventStatus.SENDING);
         expect(ev2.status).toEqual(EventStatus.SENDING);
 
-        // give the reactor a chance to run, so that ev2 gets queued
+        // the first message should get sent, and the second should get queued
-        q().then(function() {
+        httpBackend.when("PUT", "/send/m.room.message/").check(function(rq) {
             // ev2 should now have been queued
             expect(ev2.status).toEqual(EventStatus.QUEUED);
 
@@ -82,12 +81,9 @@ describe("MatrixClient retrying", function() {
             // shouldn't be able to cancel the first message yet
             expect(function() { client.cancelPendingEvent(ev1); })
                 .toThrow();
+        }).respond(400); // fail the first message
 
-            // fail the first send
+        httpBackend.flush().then(function() {
-            httpBackend.when("PUT", "/send/m.room.message/")
-                .respond(400);
-            return httpBackend.flush();
-        }).then(function() {
             expect(ev1.status).toEqual(EventStatus.NOT_SENT);
             expect(tl.length).toEqual(1);