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