feat(chat) add support for sending and receiving reactions

JitsiConference.js

@@ -970,6 +970,18 @@ JitsiConference.prototype.sendTextMessage = function(message, elementName = 'bod
     }
 };
 
+/**
+ * Sends a reaction to the other participants in the conference
+ * @param reaction the reaction.
+ * @param messageId the ID of the message to attach the reaction to.
+ * @param receiverId the intended recipient, if the message is private.
+ */
+JitsiConference.prototype.sendReaction = function(reaction, messageId, receiverId) {
+    if (this.room) {
+        this.room.sendReaction(reaction, messageId, receiverId);
+    }
+};
+
 /**
  * Send private text message to another participant of the conference
  * @param id the id of the participant to send a private message.

JitsiConferenceEventManager.js

@@ -376,6 +376,16 @@ JitsiConferenceEventManager.prototype.setupChatRoomListeners = function() {
                 participantId, txt, ts, nick, isGuest, messageId);
         });
 
+    chatRoom.addListener(
+        XMPPEvents.REACTION_RECEIVED,
+
+        (jid, reactionList, messageId) => {
+
+            conference.eventEmitter.emit(
+                JitsiConferenceEvents.REACTION_RECEIVED,
+                jid, reactionList, messageId);
+        });
+
     chatRoom.addListener(
         XMPPEvents.PRIVATE_MESSAGE_RECEIVED,
 

JitsiConferenceEvents.ts

@@ -284,6 +284,11 @@ export enum JitsiConferenceEvents {
      */
     MESSAGE_RECEIVED = 'conference.messageReceived',
 
+    /**
+     * New reaction was received.
+     */
+    REACTION_RECEIVED = 'conference.reactionReceived',
+
     /**
      * Event fired when the conference metadata is updated.
      */

modules/xmpp/ChatRoom.js

@@ -962,6 +962,26 @@ export default class ChatRoom extends Listenable {
         this.eventEmitter.emit(XMPPEvents.SENDING_CHAT_MESSAGE, message);
     }
 
+    /**
+     * Sends a reaction message to the other participants in the conference.
+     * @param {string} reaction - The reaction being sent.
+     * @param {string} messageId - The id of the message being sent.
+     * @param {string} receiverId - The receiver of the message if it is private.
+     */
+    sendReaction(reaction, messageId, receiverId) {
+        // Adds the 'to' attribute depending on if the message is private or not.
+        const msg = receiverId ? $msg({ to: `${this.roomjid}/${receiverId}`,
+            type: 'chat' }) : $msg({ to: this.roomjid,
+            type: 'groupchat' });
+
+        msg.c('reactions', { id: messageId,
+            xmlns: 'urn:xmpp:reactions:0' })
+            .c('reaction', {}, reaction)
+            .up().c('store', { xmlns: 'urn:xmpp:hints' });
+
+        this.connection.send(msg);
+    }
+
     /* eslint-disable max-params */
     /**
      * Send private text message to another participant of the conference
@@ -1144,6 +1164,24 @@ export default class ChatRoom extends Listenable {
             return true;
         }
 
+        const reactions = $(msg).find('>[xmlns="urn:xmpp:reactions:0"]>reaction');
+
+        if (reactions.length > 0) {
+            const messageId = $(msg).find('>[xmlns="urn:xmpp:reactions:0"]').attr('id');
+            const reactionList = [];
+
+            reactions.each((_, reactionElem) => {
+                const reaction = $(reactionElem).text();
+
+                reactionList.push(reaction);
+            });
+
+            this.eventEmitter.emit(XMPPEvents.REACTION_RECEIVED, from, reactionList, messageId);
+
+            return true;
+        }
+
+
         const txt = $(msg).find('>body').text();
         const subject = $(msg).find('>subject');
 

service/xmpp/XMPPEvents.ts

@@ -122,6 +122,10 @@ export enum XMPPEvents {
     // received.
     MESSAGE_RECEIVED = 'xmpp.message_received',
 
+    // Designates an event indicating that a reaction XMPP message in the MUC
+    // was received.
+    REACTION_RECEIVED = "xmpp.reaction_received",
+
     // Designates an event indicating that an invite XMPP message in the MUC was
     // received.
     INVITE_MESSAGE_RECEIVED = 'xmpp.invite_message_received',