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.js'
   8 import { UIServerUtils } from './UIServerUtils.js'
   9 import {
  10   type ProtocolRequest,
  11   type ProtocolResponse,
  12   type UIServerConfiguration,
  13   WebSocketCloseEventStatusCode
  14 } from '../../types/index.js'
  15 import {
  16   Constants,
  17   JSONStringifyWithMapSupport,
  18   getWebSocketCloseEventStatusString,
  19   isNotEmptyString,
  20   logPrefix,
  21   logger,
  22   validateUUID
  23 } from '../../utils/index.js'
  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     this.webSocketServer.on('connection', (ws: WebSocket, _req: IncomingMessage): void => {
  40       if (!UIServerUtils.isProtocolAndVersionSupported(ws.protocol)) {
  41         logger.error(
  42           `${this.logPrefix(
  43             moduleName,
  44             'start.server.onconnection'
  45           )} Unsupported UI protocol version: '${ws.protocol}'`
  46         )
  47         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR)
  48       }
  49       const [, version] = UIServerUtils.getProtocolAndVersion(ws.protocol)
  50       this.registerProtocolVersionUIService(version)
  51       ws.on('message', rawData => {
  52         const request = this.validateRawDataRequest(rawData)
  53         if (request === false) {
  54           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD)
  55           return
  56         }
  57         const [requestId] = request
  58         this.responseHandlers.set(requestId, ws)
  59         this.uiServices
  60           .get(version)
  61           ?.requestHandler(request)
  62           .then((protocolResponse?: ProtocolResponse) => {
  63             if (protocolResponse != null) {
  64               this.sendResponse(protocolResponse)
  65             }
  66           })
  67           .catch(Constants.EMPTY_FUNCTION)
  68       })
  69       ws.on('error', error => {
  70         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error)
  71       })
  72       ws.on('close', (code, reason) => {
  73         logger.debug(
  74           `${this.logPrefix(
  75             moduleName,
  76             'start.ws.onclose'
  77           )} WebSocket closed: '${getWebSocketCloseEventStatusString(
  78             code
  79           )}' - '${reason.toString()}'`
  80         )
  81       })
  82     })
  83     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, _head: Buffer) => {
  84       if (req.headers.connection !== 'Upgrade' || req.headers.upgrade !== 'websocket') {
  85         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`)
  86         socket.destroy()
  87       }
  88     })
  89     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  90       this.authenticate(req, err => {
  91         if (err != null) {
  92           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`)
  93           socket.destroy()
  94           return
  95         }
  96         try {
  97           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  98             this.webSocketServer.emit('connection', ws, req)
  99           })
 100         } catch (error) {
 101           logger.error(
 102             `${this.logPrefix(
 103               moduleName,
 104               'start.httpServer.on.upgrade'
 105             )} Error at handling connection upgrade:`,
 106             error
 107           )
 108         }
 109       })
 110     })
 111     this.startHttpServer()
 112   }
 113
 114   public sendRequest (request: ProtocolRequest): void {
 115     this.broadcastToClients(JSON.stringify(request))
 116   }
 117
 118   public sendResponse (response: ProtocolResponse): void {
 119     const responseId = response[0]
 120     try {
 121       if (this.hasResponseHandler(responseId)) {
 122         const ws = this.responseHandlers.get(responseId) as WebSocket
 123         if (ws.readyState === WebSocket.OPEN) {
 124           ws.send(JSONStringifyWithMapSupport(response))
 125         } else {
 126           logger.error(
 127             `${this.logPrefix(
 128               moduleName,
 129               'sendResponse'
 130             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 131               ws.readyState
 132             }`
 133           )
 134         }
 135       } else {
 136         logger.error(
 137           `${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 =
 158       prefixSuffix != null ? `UI WebSocket Server ${prefixSuffix}` : 'UI WebSocket Server'
 159     const logMsg =
 160       isNotEmptyString(modName) && isNotEmptyString(methodName)
 161         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 162         : ` ${logMsgPrefix} |`
 163     return logPrefix(logMsg)
 164   }
 165
 166   private broadcastToClients (message: string): void {
 167     for (const client of this.webSocketServer.clients) {
 168       if (client.readyState === WebSocket.OPEN) {
 169         client.send(message)
 170       }
 171     }
 172   }
 173
 174   private validateRawDataRequest (rawData: RawData): ProtocolRequest | false {
 175     // logger.debug(
 176     //   `${this.logPrefix(
 177     //     moduleName,
 178     //     'validateRawDataRequest'
 179     //     // eslint-disable-next-line @typescript-eslint/no-base-to-string
 180     //   )} Raw data received in string format: ${rawData.toString()}`
 181     // )
 182
 183     let request: ProtocolRequest
 184     try {
 185       // eslint-disable-next-line @typescript-eslint/no-base-to-string
 186       request = JSON.parse(rawData.toString()) as ProtocolRequest
 187     } catch (error) {
 188       logger.error(
 189         `${this.logPrefix(
 190           moduleName,
 191           'validateRawDataRequest'
 192           // eslint-disable-next-line @typescript-eslint/no-base-to-string
 193         )} UI protocol request is not valid JSON: ${rawData.toString()}`
 194       )
 195       return false
 196     }
 197
 198     if (!Array.isArray(request)) {
 199       logger.error(
 200         `${this.logPrefix(
 201           moduleName,
 202           'validateRawDataRequest'
 203         )} UI protocol request is not an array:`,
 204         request
 205       )
 206       return false
 207     }
 208
 209     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 210     if (request.length !== 3) {
 211       logger.error(
 212         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 213         request
 214       )
 215       return false
 216     }
 217
 218     if (!validateUUID(request[0])) {
 219       logger.error(
 220         `${this.logPrefix(
 221           moduleName,
 222           'validateRawDataRequest'
 223         )} UI protocol request UUID field is invalid:`,
 224         request
 225       )
 226       return false
 227     }
 228
 229     return request
 230   }
 231 }