add "timeline" system for measuring app start performance

frontend/src/auth.js

@@ -1,6 +1,7 @@
 import gateway, { GatewayEventType } from "./gateway";
 import { removeItem, setItem } from "./storage";
 import { overlayStore, OverlayType } from "./stores";
+import { timeline } from "./timeline";
 
 export function useAuthHandlers() {
     gateway.subscribe(GatewayEventType.Ready, () => {
@@ -14,6 +15,7 @@ export function useAuthHandlers() {
 }
 
 export function authWithToken(token, shouldUpdate=false) {
+    timeline.addCheckpoint("Authentication started (authWithToken)");
     if (shouldUpdate)
         setItem("auth:token", token);
     gateway.init(token);

frontend/src/components/Main.svelte

@@ -1,9 +1,19 @@
 <script>
+    import { afterUpdate, beforeUpdate } from "svelte";
     import { showSidebar, selectedChannel, smallViewport, showChannelView, theme, showPresenceSidebar } from "../stores";
+    import { timeline } from "../timeline";
     import ChannelView from "./ChannelView.svelte";
     import OverlayProvider from "./overlays/OverlayProvider.svelte";
     import PresenceSidebar from "./PresenceSidebar.svelte";
     import Sidebar from "./Sidebar.svelte";
+
+    beforeUpdate(() => {
+        timeline.addCheckpoint("Main component update start");
+    });
+
+    afterUpdate(() => {
+        timeline.addCheckpoint("Main component update end");
+    });
 </script>
 
 <svelte:head>

frontend/src/debuggingapi.js

@@ -2,6 +2,7 @@ import gateway from './gateway';
 import { getItem, init, setItem, removeItem } from './storage';
 import { allStores } from './stores';
 import { authWithToken, logOut } from './auth';
+import { timeline } from './timeline';
 
 export function useDebuggingApi() {
     window.__waffle = {
@@ -16,6 +17,7 @@ export function useDebuggingApi() {
             authWithToken,
             logOut
         },
+        timeline,
         stores: allStores,
         app: null
     };

frontend/src/gateway.js

@@ -1,5 +1,6 @@
 import logger from "./logging";
 import { getItem } from "./storage";
+import { timeline } from "./timeline";
 
 export const GatewayErrors = {
     BAD_PAYLOAD: 4001,
@@ -58,6 +59,7 @@ export default {
     handlers: new Map(),
     disableReconnect: false,
     init(token) {
+        timeline.addCheckpoint("Gateway connection start");
         if (!token) {
             log("no auth token, skipping connection");
             this.dispatch(GatewayEventType.Close, GatewayErrors.BAD_AUTH);
@@ -67,6 +69,7 @@ export default {
         log(`connecting to gateway - gatewayBase: ${getItem("server:gatewayBase")}`);
         this.ws = new WebSocket(getItem("server:gatewayBase"));
         this.ws.onopen = () => {
+            timeline.addCheckpoint("Gateway connection open");
             if (this.reconnectTimeout) {
                 clearTimeout(this.reconnectTimeout);
             }
@@ -80,6 +83,7 @@ export default {
 
             switch (payload.t) {
                 case GatewayPayloadType.Hello: {
+                    timeline.addCheckpoint("Gateway hello");
                     this.send({
                         t: GatewayPayloadType.Authenticate,
                         d: {
@@ -98,6 +102,8 @@ export default {
                     break;
                 }
                 case GatewayPayloadType.Ready: {
+                    timeline.addCheckpoint("Gateway ready");
+
                     this.user = payload.d.user;
                     this.channels = payload.d.channels;
 
@@ -111,6 +117,7 @@ export default {
             this.dispatch(payload.t, payload.d);
         };
         this.ws.onclose = ({ code }) => {
+            timeline.addCheckpoint("Gateway close");
             this.authenticated = false;
             this.user = null;
             this.channels = null;

frontend/src/logging.js

@@ -11,3 +11,11 @@ export default function logger(sink) {
         }
     };
 }
+
+export function tableLogger(sink) {
+    return (...args) => {
+        if (getItem(`log:${sink}`)) {
+            console.table(...args);
+        }
+    };
+}

frontend/src/main.js

@@ -7,8 +7,13 @@ import gateway, { GatewayEventType } from './gateway';
 import { pluginStore } from './stores';
 
 import "@material-design-icons/font";
+import { timeline } from './timeline';
+
+timeline.start();
 
 function handleGatewaySettlement() {
+    timeline.addCheckpoint("Got gateway settlement");
+
     const loadingElement = document.getElementById("pre--loading-screen");
     if (loadingElement) {
         loadingElement.parentElement.removeChild(loadingElement);
@@ -19,6 +24,8 @@ function handleGatewaySettlement() {
     });
     window.__waffle.app = app;
 
+    timeline.addCheckpoint("Created application");
+
     pluginStore.consumePluginLoaders();
     const scripts = getItem("app:javascript");
     scripts.forEach((script) => {
@@ -32,11 +39,17 @@ function handleGatewaySettlement() {
         document.head.appendChild(style);
     });
 
+    timeline.addCheckpoint("Loaded custom user content");
+
     gateway.unsubscribe(GatewayEventType.Ready, handleGatewaySettlement);
     gateway.unsubscribe(GatewayEventType.Close, handleGatewaySettlement);
+
+    timeline.addCheckpoint("All initialization finished");
+    timeline.dump();
 }
 
 function main() {
+    timeline.addCheckpoint("Main reached");
     useDebuggingApi();
     useAuthHandlers();
     initResponsiveHandlers();

frontend/src/storage.js

@@ -8,6 +8,7 @@ const defaults = {
     "log:Gateway": false,
     "log:Store": false,
     "log:Messages": false,
+    "log:Timeline": false,
     "ui:stateful:presistSelectedChannel": true,
     "ui:showSidebarToggle": false,
     "ui:alwaysUseMobileChatBar": false,

frontend/src/timeline.js

@@ -0,0 +1,28 @@
+import { tableLogger } from "./logging";
+
+export class Timeline {
+    constructor() {
+        this.startedAt = -1;
+        this.checkpoints = [];
+        this.logger = tableLogger("Timeline");
+    }
+
+    start() {
+        this.startedAt = performance.now();
+        this.checkpoints.push({
+            offset: 0,
+            label: "Timeline Started"
+        });
+    }
+
+    addCheckpoint(label) {
+        const offset = performance.now() - this.startedAt;
+        this.checkpoints.push({ offset, label });
+    }
+
+    dump() {
+        this.logger(this.checkpoints);
+    }
+}
+
+export const timeline = new Timeline();