Notes/public/javascripts/messaging.js

"use strict";

const messaging = (function() {
    let ws = null;

    function logError(message) {
        console.error(message);

        if (ws && ws.readyState === 1) {
            ws.send(JSON.stringify({
                type: 'log-error',
                error: message
            }));
        }
    }

    function messageHandler(event) {
        const message = JSON.parse(event.data);

        if (message.type === 'sync') {
            lastPingTs = new Date().getTime();
            const data = message.data;

            if (data.notes_tree) {
                console.log("Reloading tree because of background changes");

                noteTree.reload();
            }

            if (data.notes && data.notes.includes(noteEditor.getCurrentNoteId())) {
                showMessage('Reloading note because background change');

                noteEditor.reload();
            }

            const changesToPushCountEl = $("#changesToPushCount");
            changesToPushCountEl.html(message.changesToPushCount);
        }
    }

    function connectWebSocket() {
        // use wss for secure messaging
        ws = new WebSocket("ws://" + location.host);
        ws.onopen = function (event) {};
        ws.onmessage = messageHandler;
        ws.onclose = function(){
            // Try to reconnect in 5 seconds
            setTimeout(() => connectWebSocket(), 5000);
        };
    }

    connectWebSocket();

    let lastPingTs = new Date().getTime();
    let connectionBrokenNotification = null;

    setInterval(async () => {
        if (new Date().getTime() - lastPingTs > 5000) {
            if (!connectionBrokenNotification) {
                connectionBrokenNotification = $.notify({
                    // options
                    message: "Lost connection to server"
                },{
                    // settings
                    type: 'danger',
                    delay: 100000000 // keep it until we explicitly close it
                });
            }
        }
        else if (connectionBrokenNotification) {
            await connectionBrokenNotification.close();
            connectionBrokenNotification = null;

            showMessage("Re-connected to server");
        }
    }, 3000);

    return {
        logError
    };
})();