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 { type RawData, WebSocket, WebSocketServer } from 'ws';
   6
   7 import { AbstractUIServer } from './AbstractUIServer';
   8 import { UIServerUtils } from './UIServerUtils';
   9 import {
  10   type ProtocolRequest,
  11   type ProtocolResponse,
  12   type UIServerConfiguration,
  13   WebSocketCloseEventStatusCode,
  14 } from '../../types';
  15 import {
  16   Constants,
  17   getWebSocketCloseEventStatusString,
  18   isNotEmptyString,
  19   isNullOrUndefined,
  20   logPrefix,
  21   logger,
  22   validateUUID,
  23 } from '../../utils';
  24
  25 const moduleName = 'UIWebSocketServer';
  26
  27 export class UIWebSocketServer extends AbstractUIServer {
  28   private readonly webSocketServer: WebSocketServer;
  29
  30   public constructor(protected readonly uiServerConfiguration: UIServerConfiguration) {
  31     super(uiServerConfiguration);
  32     this.webSocketServer = new WebSocketServer({
  33       handleProtocols: UIServerUtils.handleProtocols,
  34       noServer: true,
  35     });
  36   }
  37
  38   public start(): void {
  39     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  40     this.webSocketServer.on('connection', (ws: WebSocket, req: IncomingMessage): void => {
  41       if (UIServerUtils.isProtocolAndVersionSupported(ws.protocol) === false) {
  42         logger.error(
  43           `${this.logPrefix(
  44             moduleName,
  45             'start.server.onconnection',
  46           )} Unsupported UI protocol version: '${ws.protocol}'`,
  47         );
  48         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR);
  49       }
  50       const [, version] = UIServerUtils.getProtocolAndVersion(ws.protocol);
  51       this.registerProtocolVersionUIService(version);
  52       ws.on('message', (rawData) => {
  53         const request = this.validateRawDataRequest(rawData);
  54         if (request === false) {
  55           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD);
  56           return;
  57         }
  58         const [requestId] = request as ProtocolRequest;
  59         this.responseHandlers.set(requestId, ws);
  60         this.uiServices
  61           .get(version)
  62           ?.requestHandler(request)
  63           .then((protocolResponse: ProtocolResponse) => {
  64             if (!isNullOrUndefined(protocolResponse)) {
  65               this.sendResponse(protocolResponse);
  66             }
  67           })
  68           .catch(Constants.EMPTY_FUNCTION);
  69       });
  70       ws.on('error', (error) => {
  71         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error);
  72       });
  73       ws.on('close', (code, reason) => {
  74         logger.debug(
  75           `${this.logPrefix(
  76             moduleName,
  77             'start.ws.onclose',
  78           )} WebSocket closed: '${getWebSocketCloseEventStatusString(
  79             code,
  80           )}' - '${reason.toString()}'`,
  81         );
  82       });
  83     });
  84     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  85     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, head: Buffer) => {
  86       if (req.headers?.connection !== 'Upgrade' || req.headers?.upgrade !== 'websocket') {
  87         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`);
  88         socket.destroy();
  89       }
  90     });
  91     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  92       this.authenticate(req, (err) => {
  93         if (err) {
  94           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`);
  95           socket.destroy();
  96           return;
  97         }
  98         try {
  99           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
 100             this.webSocketServer.emit('connection', ws, req);
 101           });
 102         } catch (error) {
 103           logger.error(
 104             `${this.logPrefix(
 105               moduleName,
 106               'start.httpServer.on.upgrade',
 107             )} Error at handling connection upgrade:`,
 108             error,
 109           );
 110         }
 111       });
 112     });
 113     this.startHttpServer();
 114   }
 115
 116   public sendRequest(request: ProtocolRequest): void {
 117     this.broadcastToClients(JSON.stringify(request));
 118   }
 119
 120   public sendResponse(response: ProtocolResponse): void {
 121     const responseId = response[0];
 122     try {
 123       if (this.hasResponseHandler(responseId)) {
 124         const ws = this.responseHandlers.get(responseId) as WebSocket;
 125         if (ws?.readyState === WebSocket.OPEN) {
 126           ws.send(JSON.stringify(response));
 127         } else {
 128           logger.error(
 129             `${this.logPrefix(
 130               moduleName,
 131               'sendResponse',
 132             )} Error at sending response id '${responseId}', WebSocket is not open: ${ws?.readyState}`,
 133           );
 134         }
 135       } else {
 136         logger.error(
 137           `${this.logPrefix(
 138             moduleName,
 139             'sendResponse',
 140           )} Response for unknown request id: ${responseId}`,
 141         );
 142       }
 143     } catch (error) {
 144       logger.error(
 145         `${this.logPrefix(
 146           moduleName,
 147           'sendResponse',
 148         )} Error at sending response id '${responseId}':`,
 149         error,
 150       );
 151     } finally {
 152       this.responseHandlers.delete(responseId);
 153     }
 154   }
 155
 156   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 157     const logMsgPrefix = prefixSuffix
 158       ? `UI WebSocket Server ${prefixSuffix}`
 159       : 'UI WebSocket Server';
 160     const logMsg =
 161       isNotEmptyString(modName) && isNotEmptyString(methodName)
 162         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 163         : ` ${logMsgPrefix} |`;
 164     return logPrefix(logMsg);
 165   };
 166
 167   private broadcastToClients(message: string): void {
 168     for (const client of this.webSocketServer.clients) {
 169       if (client?.readyState === WebSocket.OPEN) {
 170         client.send(message);
 171       }
 172     }
 173   }
 174
 175   private validateRawDataRequest(rawData: RawData): ProtocolRequest | false {
 176     // logger.debug(
 177     //   `${this.logPrefix(
 178     //     moduleName,
 179     //     'validateRawDataRequest'
 180     //   )} Raw data received in string format: ${rawData.toString()}`
 181     // );
 182
 183     const request = JSON.parse(rawData.toString()) as ProtocolRequest;
 184
 185     if (Array.isArray(request) === false) {
 186       logger.error(
 187         `${this.logPrefix(
 188           moduleName,
 189           'validateRawDataRequest',
 190         )} UI protocol request is not an array:`,
 191         request,
 192       );
 193       return false;
 194     }
 195
 196     if (request.length !== 3) {
 197       logger.error(
 198         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 199         request,
 200       );
 201       return false;
 202     }
 203
 204     if (validateUUID(request[0]) === false) {
 205       logger.error(
 206         `${this.logPrefix(
 207           moduleName,
 208           'validateRawDataRequest',
 209         )} UI protocol request UUID field is invalid:`,
 210         request,
 211       );
 212       return false;
 213     }
 214
 215     return request;
 216   }
 217 }