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

   1 import type { IncomingMessage } from 'http';
   2 import type internal from 'stream';
   3
   4 import { StatusCodes } from 'http-status-codes';
   5 import WebSocket, { type RawData, WebSocketServer } from 'ws';
   6
   7 import { AbstractUIServer } from './AbstractUIServer';
   8 import { UIServerUtils } from './UIServerUtils';
   9 import type { UIServerConfiguration } from '../../types/ConfigurationData';
  10 import type { ProtocolRequest, ProtocolResponse } from '../../types/UIProtocol';
  11 import { WebSocketCloseEventStatusCode } from '../../types/WebSocket';
  12 import logger from '../../utils/Logger';
  13 import Utils from '../../utils/Utils';
  14
  15 const moduleName = 'UIWebSocketServer';
  16
  17 export default class UIWebSocketServer extends AbstractUIServer {
  18   private readonly webSocketServer: WebSocketServer;
  19
  20   public constructor(protected readonly uiServerConfiguration: UIServerConfiguration) {
  21     super(uiServerConfiguration);
  22     this.webSocketServer = new WebSocketServer({
  23       handleProtocols: UIServerUtils.handleProtocols,
  24       noServer: true,
  25     });
  26   }
  27
  28   public start(): void {
  29     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  30     this.webSocketServer.on('connection', (ws: WebSocket, req: IncomingMessage): void => {
  31       if (UIServerUtils.isProtocolAndVersionSupported(ws.protocol) === false) {
  32         logger.error(
  33           `${this.logPrefix(
  34             moduleName,
  35             'start.server.onconnection'
  36           )} Unsupported UI protocol version: '${ws.protocol}'`
  37         );
  38         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR);
  39       }
  40       const [, version] = UIServerUtils.getProtocolAndVersion(ws.protocol);
  41       this.registerProtocolVersionUIService(version);
  42       ws.on('message', rawData => {
  43         const request = this.validateRawDataRequest(rawData);
  44         if (request === false) {
  45           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD);
  46           return;
  47         }
  48         const [requestId] = request as ProtocolRequest;
  49         this.responseHandlers.set(requestId, ws);
  50         this.uiServices
  51           .get(version)
  52           .requestHandler(request)
  53           .catch(() => {
  54             /* Error caught by AbstractUIService */
  55           });
  56       });
  57       ws.on('error', error => {
  58         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error);
  59       });
  60       ws.on('close', (code, reason) => {
  61         logger.debug(
  62           `${this.logPrefix(
  63             moduleName,
  64             'start.ws.onclose'
  65           )} WebSocket closed: '${Utils.getWebSocketCloseEventStatusString(
  66             code
  67           )}' - '${reason.toString()}'`
  68         );
  69       });
  70     });
  71     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  72     this.httpServer.on('connect', (req: IncomingMessage, socket: internal.Duplex, head: Buffer) => {
  73       if (req.headers?.connection !== 'Upgrade' || req.headers?.upgrade !== 'websocket') {
  74         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`);
  75         socket.destroy();
  76       }
  77     });
  78     this.httpServer.on(
  79       'upgrade',
  80       (req: IncomingMessage, socket: internal.Duplex, head: Buffer): void => {
  81         this.authenticate(req, err => {
  82           if (err) {
  83             socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`);
  84             socket.destroy();
  85             return;
  86           }
  87           try {
  88             this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  89               this.webSocketServer.emit('connection', ws, req);
  90             });
  91           } catch (error) {
  92             logger.error(
  93               `${this.logPrefix(
  94                 moduleName,
  95                 'start.httpServer.on.upgrade'
  96               )} Error at handling connection upgrade:`,
  97               error
  98             );
  99           }
 100         });
 101       }
 102     );
 103     this.startHttpServer();
 104   }
 105
 106   public sendRequest(request: ProtocolRequest): void {
 107     this.broadcastToClients(JSON.stringify(request));
 108   }
 109
 110   public sendResponse(response: ProtocolResponse): void {
 111     const responseId = response[0];
 112     try {
 113       if (this.responseHandlers.has(responseId)) {
 114         const ws = this.responseHandlers.get(responseId) as WebSocket;
 115         if (ws?.readyState === WebSocket.OPEN) {
 116           ws.send(JSON.stringify(response));
 117         } else {
 118           logger.error(
 119             `${this.logPrefix(
 120               moduleName,
 121               'sendResponse'
 122             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 123               ws?.readyState
 124             }`
 125           );
 126         }
 127       } else {
 128         logger.error(
 129           `${this.logPrefix(
 130             moduleName,
 131             'sendResponse'
 132           )} Response for unknown request id: ${responseId}`
 133         );
 134       }
 135     } catch (error) {
 136       logger.error(
 137         `${this.logPrefix(
 138           moduleName,
 139           'sendResponse'
 140         )} Error at sending response id '${responseId}':`,
 141         error
 142       );
 143     } finally {
 144       this.responseHandlers.delete(responseId);
 145     }
 146   }
 147
 148   public logPrefix(modName?: string, methodName?: string, prefixSuffix?: string): string {
 149     const logMsgPrefix = prefixSuffix
 150       ? `UI WebSocket Server ${prefixSuffix}`
 151       : 'UI WebSocket Server';
 152     const logMsg =
 153       modName && methodName ? ` ${logMsgPrefix} | ${modName}.${methodName}:` : ` ${logMsgPrefix} |`;
 154     return Utils.logPrefix(logMsg);
 155   }
 156
 157   private broadcastToClients(message: string): void {
 158     for (const client of this.webSocketServer.clients) {
 159       if (client?.readyState === WebSocket.OPEN) {
 160         client.send(message);
 161       }
 162     }
 163   }
 164
 165   private validateRawDataRequest(rawData: RawData): ProtocolRequest | false {
 166     // logger.debug(
 167     //   `${this.logPrefix(
 168     //     moduleName,
 169     //     'validateRawDataRequest'
 170     //   )} Raw data received in string format: ${rawData.toString()}`
 171     // );
 172
 173     const request = JSON.parse(rawData.toString()) as ProtocolRequest;
 174
 175     if (Array.isArray(request) === false) {
 176       logger.error(
 177         `${this.logPrefix(
 178           moduleName,
 179           'validateRawDataRequest'
 180         )} UI protocol request is not an array:`,
 181         request
 182       );
 183       return false;
 184     }
 185
 186     if (request.length !== 3) {
 187       logger.error(
 188         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 189         request
 190       );
 191       return false;
 192     }
 193
 194     if (Utils.validateUUID(request[0]) === false) {
 195       logger.error(
 196         `${this.logPrefix(
 197           moduleName,
 198           'validateRawDataRequest'
 199         )} UI protocol request UUID field is invalid:`,
 200         request
 201       );
 202       return false;
 203     }
 204
 205     return request;
 206   }
 207 }