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

   1 import type { IncomingMessage } from 'http';
   2 import type { Duplex } from '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 { 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
  52           .get(version)
  53           ?.requestHandler(request)
  54           .catch(() => {
  55             /* Error caught by AbstractUIService */
  56           });
  57       });
  58       ws.on('error', (error) => {
  59         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error);
  60       });
  61       ws.on('close', (code, reason) => {
  62         logger.debug(
  63           `${this.logPrefix(
  64             moduleName,
  65             'start.ws.onclose'
  66           )} WebSocket closed: '${Utils.getWebSocketCloseEventStatusString(
  67             code
  68           )}' - '${reason.toString()}'`
  69         );
  70       });
  71     });
  72     // eslint-disable-next-line @typescript-eslint/no-unused-vars
  73     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, head: Buffer) => {
  74       if (req.headers?.connection !== 'Upgrade' || req.headers?.upgrade !== 'websocket') {
  75         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`);
  76         socket.destroy();
  77       }
  78     });
  79     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  80       this.authenticate(req, (err) => {
  81         if (err) {
  82           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`);
  83           socket.destroy();
  84           return;
  85         }
  86         try {
  87           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  88             this.webSocketServer.emit('connection', ws, req);
  89           });
  90         } catch (error) {
  91           logger.error(
  92             `${this.logPrefix(
  93               moduleName,
  94               'start.httpServer.on.upgrade'
  95             )} Error at handling connection upgrade:`,
  96             error
  97           );
  98         }
  99       });
 100     });
 101     this.startHttpServer();
 102   }
 103
 104   public sendRequest(request: ProtocolRequest): void {
 105     this.broadcastToClients(JSON.stringify(request));
 106   }
 107
 108   public sendResponse(response: ProtocolResponse): void {
 109     const responseId = response[0];
 110     try {
 111       if (this.responseHandlers.has(responseId)) {
 112         const ws = this.responseHandlers.get(responseId) as WebSocket;
 113         if (ws?.readyState === WebSocket.OPEN) {
 114           ws.send(JSON.stringify(response));
 115         } else {
 116           logger.error(
 117             `${this.logPrefix(
 118               moduleName,
 119               'sendResponse'
 120             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 121               ws?.readyState
 122             }`
 123           );
 124         }
 125       } else {
 126         logger.error(
 127           `${this.logPrefix(
 128             moduleName,
 129             'sendResponse'
 130           )} Response for unknown request id: ${responseId}`
 131         );
 132       }
 133     } catch (error) {
 134       logger.error(
 135         `${this.logPrefix(
 136           moduleName,
 137           'sendResponse'
 138         )} Error at sending response id '${responseId}':`,
 139         error
 140       );
 141     } finally {
 142       this.responseHandlers.delete(responseId);
 143     }
 144   }
 145
 146   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 147     const logMsgPrefix = prefixSuffix
 148       ? `UI WebSocket Server ${prefixSuffix}`
 149       : 'UI WebSocket Server';
 150     const logMsg =
 151       Utils.isNotEmptyString(modName) && Utils.isNotEmptyString(methodName)
 152         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 153         : ` ${logMsgPrefix} |`;
 154     return Utils.logPrefix(logMsg);
 155   };
 156
 157   private broadcastToClients(message: string): void {
 158     for (const client of this.webSocketServer.clients) {
 159       if (client?.readyState === WebSocket.OPEN) {
 160         client.send(message);
 161       }
 162     }
 163   }
 164
 165   private validateRawDataRequest(rawData: RawData): ProtocolRequest | false {
 166     // logger.debug(
 167     //   `${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 }