server: Move OctoPrint connection handler class to its own file

server/OctoPrintConnection.ts

@@ -0,0 +1,125 @@
+import * as WebSocket from 'ws';
+import fetch from 'node-fetch';
+
+import {ExtendedMessage} from '../types/messages';
+import * as octoprint from '../types/octoprint';
+
+const PING_TIME = 10000;
+
+type Timeout = ReturnType<typeof setTimeout>;
+
+export default class OctoprintConnection {
+  public webcamURL?: URL;
+  public name?: string;
+  protected lastStatus?: ExtendedMessage;
+
+  constructor(
+    public slug: string,
+    public address: string,
+    protected apikey: string,
+    protected broadcast: (msg: ExtendedMessage) => void
+  ) {
+    this.try_connect_websocket();
+  }
+
+  try_connect_websocket() {
+    this.connect_websocket().catch((e) => {
+      console.error(
+        `Failed to connect to "${this.slug}", attempting reconnection in 5 seconds`
+      );
+      console.error(e);
+      setTimeout(() => this.try_connect_websocket(), 5000);
+    });
+  }
+
+  async connect_websocket() {
+    const settings = await this.api_get('settings');
+    this.webcamURL = new URL(settings.webcam.streamUrl, this.address);
+    this.name = settings.appearance.name;
+
+    // do passive login to get a session key from the API key
+    const login: octoprint.LoginResponse = await this.api_post('login', {
+      passive: 'true',
+    });
+    const session_key = login.name + ':' + login.session;
+
+    let pingSender: ReturnType<typeof setInterval>;
+    let pongTimeout: Timeout;
+
+    const url = new URL('/sockjs/websocket', this.address);
+    url.protocol = 'ws';
+    let websocket = new WebSocket(url.toString());
+    websocket
+      .on('open', () => {
+        pingSender = setInterval(() => websocket.ping(), PING_TIME);
+        pongTimeout = this.heartbeat(websocket, pongTimeout);
+
+        console.log(`Connected to "${this.slug}"`);
+        websocket.send(JSON.stringify({ auth: session_key }));
+      })
+      .on('message', (data: WebSocket.Data) => {
+        const event: octoprint.Message = JSON.parse(data as string);
+
+        let ext_event: ExtendedMessage = {
+          ...event,
+          printer: this.slug,
+          name: this.name,
+        };
+        this.broadcast(ext_event);
+
+        if ('current' in event || 'history' in event) {
+          this.lastStatus = ext_event;
+        }
+      })
+      .on('pong', () => {
+        pongTimeout = this.heartbeat(websocket, pongTimeout);
+      })
+      .on('close', () => {
+        clearInterval(pingSender);
+        clearTimeout(pongTimeout);
+
+        console.log(
+          `Lost connection to "${this.slug}", attempting reconnection in 5 seconds`
+        );
+        setTimeout(() => this.try_connect_websocket(), 5000);
+      });
+  }
+
+  heartbeat(websocket: WebSocket, pongTimeout: Timeout): Timeout {
+    clearTimeout(pongTimeout);
+    return setTimeout(() => {
+      console.log(`Missed 2 heartbeats for "${this.slug}", disconnecting`);
+      websocket.terminate();
+    }, PING_TIME * 2);
+  }
+
+  async api_get(endpoint: string): Promise<any> {
+    const r = await fetch(new URL('/api/' + endpoint, this.address), {
+      headers: { 'X-Api-Key': this.apikey },
+    });
+    return await r.json();
+  }
+
+  async api_post(endpoint: string, data: any): Promise<any> {
+    const r = await fetch(new URL('/api/' + endpoint, this.address), {
+      headers: {
+        'X-Api-Key': this.apikey,
+        Accept: 'application/json',
+        'Content-Type': 'application/json',
+      },
+      method: 'POST',
+      body: JSON.stringify(data),
+    });
+    return await r.json();
+  }
+
+  send_init(ws: WebSocket) {
+    let payload: ExtendedMessage;
+    if (this.lastStatus) {
+      payload = this.lastStatus;
+    } else {
+      payload = { init: null, printer: this.slug, name: this.name };
+    }
+    ws.send(JSON.stringify(payload));
+  }
+}

server/server.ts

@@ -1,22 +1,16 @@
 import * as fs from 'fs';
-import * as path from 'path';
 
 import * as express from 'express';
-import fetch from 'node-fetch';
 import * as httpProxy from 'http-proxy';
-import * as WebSocket from 'ws';
 import * as yaml from 'js-yaml';
 import * as expressWs from 'express-ws';
+import * as WebSocket from 'ws';
 
-import * as messages from '../types/messages';
+import { ExtendedMessage } from '../types/messages';
-import * as octoprint from '../types/octoprint';
+import OctoPrintConnection from './OctoPrintConnection';
 
 const PORT = process.env.PORT || 1234;
 
-const PING_TIME = 10000;
-
-type Timeout = ReturnType<typeof setTimeout>;
-
 type configuration = {
   printers: {
     [key: string]: { address: string; apikey: string };
@@ -33,7 +27,7 @@ proxy.on('error', function (e) {
   console.error('Proxy failed:');
   console.error(e);
 });
-let printerStatuses: PrinterStatus[] = [];
+let octoprintConnections: OctoPrintConnection[] = [];
 
 function broadcast(data: WebSocket.Data) {
   wsInstance.getWss().clients.forEach((client: WebSocket) => {
@@ -43,7 +37,7 @@ function broadcast(data: WebSocket.Data) {
   });
 }
 
-function broadcastPayload(payload: messages.ExtendedMessage) {
+function broadcastPayload(payload: ExtendedMessage) {
   broadcast(JSON.stringify(payload));
 }
 
@@ -51,12 +45,12 @@ const wsInstance = expressWs(express());
 const app = wsInstance.app;
 
 app.ws('/ws', function (ws, req) {
-  printerStatuses.forEach((ps: PrinterStatus) => ps.send_init(ws));
+  octoprintConnections.forEach((op: OctoPrintConnection) => op.send_init(ws));
 });
 
 app.get('/webcam/:printer', (req, res) => {
-  let printer: PrinterStatus | undefined = printerStatuses.find(
+  let printer: OctoPrintConnection | undefined = octoprintConnections.find(
-    (p) => p.slug === req.params.printer
+    (op) => op.slug === req.params.printer
   );
   if (printer?.webcamURL) {
     req.url = ''; // truncate the url for passing to the proxy
@@ -66,129 +60,10 @@ app.get('/webcam/:printer', (req, res) => {
 
 app.listen(PORT);
 
-class PrinterStatus {
-  slug: string;
-  address: string;
-  apikey: string;
-
-  webcamURL?: URL;
-  name?: string;
-  lastStatus?: messages.ExtendedMessage;
-
-  constructor(slug: string, address: string, apikey: string) {
-    this.slug = slug;
-    this.address = address;
-    this.apikey = apikey;
-
-    this.try_connect_websocket();
-  }
-
-  try_connect_websocket() {
-    this.connect_websocket().catch((e) => {
-      console.error(
-        `Failed to connect to "${this.slug}", attempting reconnection in 5 seconds`
-      );
-      console.error(e);
-      setTimeout(() => this.try_connect_websocket(), 5000);
-    });
-  }
-
-  async connect_websocket() {
-    const settings = await this.api_get('settings');
-    this.webcamURL = new URL(settings.webcam.streamUrl, this.address);
-    this.name = settings.appearance.name;
-
-    // do passive login to get a session key from the API key
-    const login: octoprint.LoginResponse = await this.api_post('login', {
-      passive: 'true',
-    });
-    const session_key = login.name + ':' + login.session;
-
-    let pingSender: ReturnType<typeof setInterval>;
-    let pongTimeout: Timeout;
-
-    const url = new URL('/sockjs/websocket', this.address);
-    url.protocol = 'ws';
-    let websocket = new WebSocket(url.toString());
-    websocket
-      .on('open', () => {
-        pingSender = setInterval(() => websocket.ping(), PING_TIME);
-        pongTimeout = this.heartbeat(websocket, pongTimeout);
-
-        console.log(`Connected to "${this.slug}"`);
-        websocket.send(JSON.stringify({ auth: session_key }));
-      })
-      .on('message', (data: WebSocket.Data) => {
-        const event: octoprint.Message = JSON.parse(data as string);
-
-        let ext_event: messages.ExtendedMessage = {
-          ...event,
-          printer: this.slug,
-          name: this.name,
-        };
-        broadcastPayload(ext_event);
-
-        if ('current' in event || 'history' in event) {
-          this.lastStatus = ext_event;
-        }
-      })
-      .on('pong', () => {
-        pongTimeout = this.heartbeat(websocket, pongTimeout);
-      })
-      .on('close', () => {
-        clearInterval(pingSender);
-        clearTimeout(pongTimeout);
-
-        console.log(
-          `Lost connection to "${this.slug}", attempting reconnection in 5 seconds`
-        );
-        setTimeout(() => this.try_connect_websocket(), 5000);
-      });
-  }
-
-  heartbeat(websocket: WebSocket, pongTimeout: Timeout): Timeout {
-    clearTimeout(pongTimeout);
-    return setTimeout(() => {
-      console.log(`Missed 2 heartbeats for "${this.slug}", disconnecting`);
-      websocket.terminate();
-    }, PING_TIME * 2);
-  }
-
-  async api_get(endpoint: string): Promise<any> {
-    const r = await fetch(new URL('/api/' + endpoint, this.address), {
-      headers: { 'X-Api-Key': this.apikey },
-    });
-    return await r.json();
-  }
-
-  async api_post(endpoint: string, data: any): Promise<any> {
-    const r = await fetch(new URL('/api/' + endpoint, this.address), {
-      headers: {
-        'X-Api-Key': this.apikey,
-        Accept: 'application/json',
-        'Content-Type': 'application/json',
-      },
-      method: 'POST',
-      body: JSON.stringify(data),
-    });
-    return await r.json();
-  }
-
-  send_init(ws: WebSocket) {
-    let payload: messages.ExtendedMessage;
-    if (this.lastStatus) {
-      payload = this.lastStatus;
-    } else {
-      payload = { init: null, printer: this.slug, name: this.name };
-    }
-    ws.send(JSON.stringify(payload));
-  }
-}
-
 function initPrinters() {
-  printerStatuses = Object.entries(config.printers).map(
+  octoprintConnections = Object.entries(config.printers).map(
     ([slug, printer]) =>
-      new PrinterStatus(slug, printer.address, printer.apikey)
+      new OctoPrintConnection(slug, printer.address, printer.apikey, broadcastPayload)
   );
 }