src/charging-station/ui-server/UIWebSocketServer.ts

   1 import type { IncomingMessage } from 'node:http';
   2 import type { Duplex } from 'node:stream';
   3
   4 import { StatusCodes } from 'http-status-codes';
   5 import WebSocket, { type RawData, WebSocketServer } from 'ws';
   6
   7 import {
   8   type ProtocolRequest,
   9   type ProtocolResponse,
  10   type UIServerConfiguration,
  11   WebSocketCloseEventStatusCode,
  12 } from '../../types';
  13 import { Constants, Utils, logger } from '../../utils';
  14 import { AbstractUIServer, UIServerUtils } from '../internal';
  15
  16 const moduleName = 'UIWebSocketServer';
  17
  18 export class UIWebSocketServer extends AbstractUIServer {
  19   private readonly webSocketServer: WebSocketServer;
  20
  21   public constructor(protected readonly uiServerConfiguration: UIServerConfiguration) {
  22     super(uiServerConfiguration);
  23     this.webSocketServer = new WebSocketServer({
  24       handleProtocols: UIServerUtils.handleProtocols,
  25       noServer: true,
  26     });
  27   }
  28
  29   public start(): void {
  30     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  31     this.webSocketServer.on('connection', (ws: WebSocket, req: IncomingMessage): void => {
  32       if (UIServerUtils.isProtocolAndVersionSupported(ws.protocol) === false) {
  33         logger.error(
  34           `${this.logPrefix(
  35             moduleName,
  36             'start.server.onconnection'
  37           )} Unsupported UI protocol version: '${ws.protocol}'`
  38         );
  39         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR);
  40       }
  41       const [, version] = UIServerUtils.getProtocolAndVersion(ws.protocol);
  42       this.registerProtocolVersionUIService(version);
  43       ws.on('message', (rawData) => {
  44         const request = this.validateRawDataRequest(rawData);
  45         if (request === false) {
  46           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD);
  47           return;
  48         }
  49         const [requestId] = request as ProtocolRequest;
  50         this.responseHandlers.set(requestId, ws);
  51         this.uiServices.get(version)?.requestHandler(request).catch(Constants.EMPTY_FUNCTION);
  52       });
  53       ws.on('error', (error) => {
  54         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error);
  55       });
  56       ws.on('close', (code, reason) => {
  57         logger.debug(
  58           `${this.logPrefix(
  59             moduleName,
  60             'start.ws.onclose'
  61           )} WebSocket closed: '${Utils.getWebSocketCloseEventStatusString(
  62             code
  63           )}' - '${reason.toString()}'`
  64         );
  65       });
  66     });
  67     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  68     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, head: Buffer) => {
  69       if (req.headers?.connection !== 'Upgrade' || req.headers?.upgrade !== 'websocket') {
  70         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`);
  71         socket.destroy();
  72       }
  73     });
  74     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  75       this.authenticate(req, (err) => {
  76         if (err) {
  77           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`);
  78           socket.destroy();
  79           return;
  80         }
  81         try {
  82           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  83             this.webSocketServer.emit('connection', ws, req);
  84           });
  85         } catch (error) {
  86           logger.error(
  87             `${this.logPrefix(
  88               moduleName,
  89               'start.httpServer.on.upgrade'
  90             )} Error at handling connection upgrade:`,
  91             error
  92           );
  93         }
  94       });
  95     });
  96     this.startHttpServer();
  97   }
  98
  99   public sendRequest(request: ProtocolRequest): void {
 100     this.broadcastToClients(JSON.stringify(request));
 101   }
 102
 103   public sendResponse(response: ProtocolResponse): void {
 104     const responseId = response[0];
 105     try {
 106       if (this.responseHandlers.has(responseId)) {
 107         const ws = this.responseHandlers.get(responseId) as WebSocket;
 108         if (ws?.readyState === WebSocket.OPEN) {
 109           ws.send(JSON.stringify(response));
 110         } else {
 111           logger.error(
 112             `${this.logPrefix(
 113               moduleName,
 114               'sendResponse'
 115             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 116               ws?.readyState
 117             }`
 118           );
 119         }
 120       } else {
 121         logger.error(
 122           `${this.logPrefix(
 123             moduleName,
 124             'sendResponse'
 125           )} Response for unknown request id: ${responseId}`
 126         );
 127       }
 128     } catch (error) {
 129       logger.error(
 130         `${this.logPrefix(
 131           moduleName,
 132           'sendResponse'
 133         )} Error at sending response id '${responseId}':`,
 134         error
 135       );
 136     } finally {
 137       this.responseHandlers.delete(responseId);
 138     }
 139   }
 140
 141   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 142     const logMsgPrefix = prefixSuffix
 143       ? `UI WebSocket Server ${prefixSuffix}`
 144       : 'UI WebSocket Server';
 145     const logMsg =
 146       Utils.isNotEmptyString(modName) && Utils.isNotEmptyString(methodName)
 147         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 148         : ` ${logMsgPrefix} |`;
 149     return Utils.logPrefix(logMsg);
 150   };
 151
 152   private broadcastToClients(message: string): void {
 153     for (const client of this.webSocketServer.clients) {
 154       if (client?.readyState === WebSocket.OPEN) {
 155         client.send(message);
 156       }
 157     }
 158   }
 159
 160   private validateRawDataRequest(rawData: RawData): ProtocolRequest | false {
 161     // logger.debug(
 162     //   `${this.logPrefix(
 163     //     moduleName,
 164     //     'validateRawDataRequest'
 165     //   )} Raw data received in string format: ${rawData.toString()}`
 166     // );
 167
 168     const request = JSON.parse(rawData.toString()) as ProtocolRequest;
 169
 170     if (Array.isArray(request) === false) {
 171       logger.error(
 172         `${this.logPrefix(
 173           moduleName,
 174           'validateRawDataRequest'
 175         )} UI protocol request is not an array:`,
 176         request
 177       );
 178       return false;
 179     }
 180
 181     if (request.length !== 3) {
 182       logger.error(
 183         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 184         request
 185       );
 186       return false;
 187     }
 188
 189     if (Utils.validateUUID(request[0]) === false) {
 190       logger.error(
 191         `${this.logPrefix(
 192           moduleName,
 193           'validateRawDataRequest'
 194         )} UI protocol request UUID field is invalid:`,
 195         request
 196       );
 197       return false;
 198     }
 199
 200     return request;
 201   }
 202 }