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 * as uuid from 'uuid';
   6 import WebSocket, { type RawData, WebSocketServer } from 'ws';
   7
   8 import type { UIServerConfiguration } from '../../types/ConfigurationData';
   9 import type { ProtocolRequest, ProtocolResponse } from '../../types/UIProtocol';
  10 import { WebSocketCloseEventStatusCode } from '../../types/WebSocket';
  11 import logger from '../../utils/Logger';
  12 import Utils from '../../utils/Utils';
  13 import { AbstractUIServer } from './AbstractUIServer';
  14 import { UIServerUtils } from './UIServerUtils';
  15
  16 const moduleName = 'UIWebSocketServer';
  17
  18 export default 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     this.httpServer.on(
  73       'upgrade',
  74       (req: IncomingMessage, socket: internal.Duplex, head: Buffer): void => {
  75         this.authenticate(req, (err) => {
  76           if (err) {
  77             socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`);
  78             socket.destroy();
  79             return;
  80           }
  81           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  82             this.webSocketServer.emit('connection', ws, req);
  83           });
  84         });
  85       }
  86     );
  87     this.startHttpServer();
  88   }
  89
  90   public sendRequest(request: ProtocolRequest): void {
  91     this.broadcastToClients(JSON.stringify(request));
  92   }
  93
  94   public sendResponse(response: ProtocolResponse): void {
  95     const responseId = response[0];
  96     try {
  97       if (this.responseHandlers.has(responseId)) {
  98         const ws = this.responseHandlers.get(responseId) as WebSocket;
  99         if (ws?.readyState === WebSocket.OPEN) {
 100           ws.send(JSON.stringify(response));
 101         } else {
 102           logger.error(
 103             `${this.logPrefix(
 104               moduleName,
 105               'sendResponse'
 106             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 107               ws?.readyState
 108             }`
 109           );
 110         }
 111       } else {
 112         logger.error(
 113           `${this.logPrefix(
 114             moduleName,
 115             'sendResponse'
 116           )} Response for unknown request id: ${responseId}`
 117         );
 118       }
 119     } catch (error) {
 120       logger.error(
 121         `${this.logPrefix(
 122           moduleName,
 123           'sendResponse'
 124         )} Error at sending response id '${responseId}':`,
 125         error
 126       );
 127     } finally {
 128       this.responseHandlers.delete(responseId);
 129     }
 130   }
 131
 132   public logPrefix(modName?: string, methodName?: string, prefixSuffix?: string): string {
 133     const logMsgPrefix = prefixSuffix
 134       ? `UI WebSocket Server ${prefixSuffix}`
 135       : 'UI WebSocket Server';
 136     const logMsg =
 137       modName && methodName ? ` ${logMsgPrefix} | ${modName}.${methodName}:` : ` ${logMsgPrefix} |`;
 138     return Utils.logPrefix(logMsg);
 139   }
 140
 141   private broadcastToClients(message: string): void {
 142     for (const client of this.webSocketServer.clients) {
 143       if (client?.readyState === WebSocket.OPEN) {
 144         client.send(message);
 145       }
 146     }
 147   }
 148
 149   private validateRawDataRequest(rawData: RawData): ProtocolRequest | false {
 150     // logger.debug(
 151     //   `${this.logPrefix(
 152     //     moduleName,
 153     //     'validateRawDataRequest'
 154     //   )} Raw data received in string format: ${rawData.toString()}`
 155     // );
 156
 157     const request = JSON.parse(rawData.toString()) as ProtocolRequest;
 158
 159     if (Array.isArray(request) === false) {
 160       logger.error(
 161         `${this.logPrefix(
 162           moduleName,
 163           'validateRawDataRequest'
 164         )} UI protocol request is not an array:`,
 165         request
 166       );
 167       return false;
 168     }
 169
 170     if (request.length !== 3) {
 171       logger.error(
 172         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 173         request
 174       );
 175       return false;
 176     }
 177
 178     if (uuid.validate(request[0]) === false) {
 179       logger.error(
 180         `${this.logPrefix(
 181           moduleName,
 182           'validateRawDataRequest'
 183         )} UI protocol request UUID field is invalid:`,
 184         request
 185       );
 186       return false;
 187     }
 188
 189     return request;
 190   }
 191 }