renamed "messagingService" to "ws"

src/public/javascripts/services/ws.js

@@ -0,0 +1,116 @@
+import utils from './utils.js';
+import infoService from "./info.js";
+
+const $outstandingSyncsCount = $("#outstanding-syncs-count");
+
+const allSyncMessageHandlers = [];
+const outsideSyncMessageHandlers = [];
+const messageHandlers = [];
+
+let ws;
+let lastSyncId;
+let lastPingTs;
+
+function logError(message) {
+    console.log(utils.now(), message); // needs to be separate from .trace()
+    console.trace();
+
+    if (ws && ws.readyState === 1) {
+        ws.send(JSON.stringify({
+            type: 'log-error',
+            error: message
+        }));
+    }
+}
+
+function subscribeToMessages(messageHandler) {
+    messageHandlers.push(messageHandler);
+}
+
+function subscribeToOutsideSyncMessages(messageHandler) {
+    outsideSyncMessageHandlers.push(messageHandler);
+}
+
+function subscribeToAllSyncMessages(messageHandler) {
+    allSyncMessageHandlers.push(messageHandler);
+}
+
+function handleMessage(event) {
+    const message = JSON.parse(event.data);
+
+    for (const messageHandler of messageHandlers) {
+        messageHandler(message);
+    }
+
+    if (message.type === 'sync') {
+        lastPingTs = Date.now();
+
+        if (message.data.length > 0) {
+            console.debug(utils.now(), "Sync data: ", message.data);
+
+            lastSyncId = message.data[message.data.length - 1].id;
+        }
+
+        for (const syncMessageHandler of allSyncMessageHandlers) {
+            syncMessageHandler(message.data);
+        }
+
+        const syncData = message.data.filter(sync => sync.sourceId !== glob.sourceId);
+
+        for (const syncMessageHandler of outsideSyncMessageHandlers) {
+            syncMessageHandler(syncData);
+        }
+
+        $outstandingSyncsCount.html(message.outstandingSyncs);
+    }
+    else if (message.type === 'sync-hash-check-failed') {
+        infoService.showError("Sync check failed!", 60000);
+    }
+    else if (message.type === 'consistency-checks-failed') {
+        infoService.showError("Consistency checks failed! See logs for details.", 50 * 60000);
+    }
+}
+
+function connectWebSocket() {
+    const protocol = document.location.protocol === 'https:' ? 'wss' : 'ws';
+
+    // use wss for secure messaging
+    const ws = new WebSocket(protocol + "://" + location.host);
+    ws.onopen = () => console.debug(utils.now(), "Connected to server with WebSocket");
+    ws.onmessage = handleMessage;
+    // we're not handling ws.onclose here because reconnection is done in sendPing()
+
+    return ws;
+}
+
+setTimeout(() => {
+    ws = connectWebSocket();
+
+    lastSyncId = glob.maxSyncIdAtLoad;
+    lastPingTs = Date.now();
+
+    setInterval(async () => {
+        if (Date.now() - lastPingTs > 30000) {
+            console.log("Lost connection to server");
+        }
+
+        if (ws.readyState === ws.OPEN) {
+            ws.send(JSON.stringify({
+                type: 'ping',
+                lastSyncId: lastSyncId
+            }));
+        }
+        else if (ws.readyState === ws.CLOSED || ws.readyState === ws.CLOSING) {
+            console.log("WS closed or closing, trying to reconnect");
+
+            ws = connectWebSocket();
+        }
+    }, 1000);
+}, 0);
+
+export default {
+    logError,
+    subscribeToMessages,
+    subscribeToAllSyncMessages,
+    subscribeToOutsideSyncMessages
+};