Sync announcements across partitions

src/partition/announcementrefresher.js

@@ -0,0 +1,61 @@
+import Logger from '../logger';
+import uuid from 'uuid';
+
+var SERVER;
+const SERVER_ANNOUNCEMENTS = 'serverAnnouncements';
+
+class AnnouncementRefresher {
+    constructor(pubClient, subClient) {
+        this.pubClient = pubClient;
+        this.subClient = subClient;
+        this.uuid = uuid.v4();
+        process.nextTick(this.init.bind(this));
+    }
+
+    init() {
+        SERVER = require('../server').getServer();
+        SERVER.on('announcement', this.sendAnnouncement.bind(this));
+
+        this.subClient.once('ready', () => {
+            this.subClient.on('message', this.handleMessage.bind(this));
+            this.subClient.subscribe(SERVER_ANNOUNCEMENTS);
+        });
+    }
+
+    handleMessage(channel, message) {
+        if (channel !== SERVER_ANNOUNCEMENTS) {
+            return;
+        }
+
+        var data;
+        try {
+            data = JSON.parse(message);
+        } catch (error) {
+            Logger.errlog.log('Unable to unmarshal server announcement: ' + error.stack
+                    + '\nMessage was: ' + message);
+            return;
+        }
+
+        if (data.partitionID === this.uuid) {
+            return;
+        }
+
+        SERVER.setAnnouncement({
+            title: data.title,
+            text: data.text,
+            from: data.from
+        });
+    }
+
+    sendAnnouncement(data) {
+        const message = JSON.stringify({
+            title: data.title,
+            text: data.text,
+            from: data.from,
+            partitionID: this.uuid
+        });
+        this.pubClient.publish(SERVER_ANNOUNCEMENTS, message);
+    }
+}
+
+export { AnnouncementRefresher };

src/partition/partitionmodule.js

@@ -6,6 +6,7 @@ import RedisClientProvider from 'cytube-common/lib/redis/redisclientprovider';
 import logger from 'cytube-common/lib/logger';
 import LegacyConfig from '../config';
 import path from 'path';
+import { AnnouncementRefresher } from './announcementrefresher';
 
 const PARTITION_CONFIG_PATH = path.resolve(__dirname, '..', '..', 'conf',
                                            'partitions.toml');
@@ -16,7 +17,7 @@ class PartitionModule {
     }
 
     onReady() {
-
+        this.getAnnouncementRefresher();
     }
 
     initConfig() {
@@ -69,6 +70,18 @@ class PartitionModule {
 
         return this.redisClientProvider;
     }
+
+    getAnnouncementRefresher() {
+        if (!this.announcementRefresher) {
+            const provider = this.getRedisClientProvider();
+            this.announcementRefresher = new AnnouncementRefresher(
+                    provider.get(),
+                    provider.get()
+            );
+        }
+
+        return this.announcementRefresher;
+    }
 }
 
 export { PartitionModule };