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   getWebSocketCloseEventStatusString,
  18   isNotEmptyString,
  19   logPrefix,
  20   logger,
  21   validateUUID
  22 } from '../../utils/index.js'
  23
  24 const moduleName = 'UIWebSocketServer'
  25
  26 export class UIWebSocketServer extends AbstractUIServer {
  27   private readonly webSocketServer: WebSocketServer
  28
  29   public constructor (protected readonly uiServerConfiguration: UIServerConfiguration) {
  30     super(uiServerConfiguration)
  31     this.webSocketServer = new WebSocketServer({
  32       handleProtocols: UIServerUtils.handleProtocols,
  33       noServer: true
  34     })
  35   }
  36
  37   public start (): void {
  38     this.webSocketServer.on('connection', (ws: WebSocket, _req: IncomingMessage): void => {
  39       if (!UIServerUtils.isProtocolAndVersionSupported(ws.protocol)) {
  40         logger.error(
  41           `${this.logPrefix(
  42             moduleName,
  43             'start.server.onconnection'
  44           )} Unsupported UI protocol version: '${ws.protocol}'`
  45         )
  46         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR)
  47       }
  48       const [, version] = UIServerUtils.getProtocolAndVersion(ws.protocol)
  49       this.registerProtocolVersionUIService(version)
  50       ws.on('message', (rawData) => {
  51         const request = this.validateRawDataRequest(rawData)
  52         if (request === false) {
  53           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD)
  54           return
  55         }
  56         const [requestId] = request
  57         this.responseHandlers.set(requestId, ws)
  58         this.uiServices
  59           .get(version)
  60           ?.requestHandler(request)
  61           .then((protocolResponse?: ProtocolResponse) => {
  62             if (protocolResponse != null) {
  63               this.sendResponse(protocolResponse)
  64             }
  65           })
  66           .catch(Constants.EMPTY_FUNCTION)
  67       })
  68       ws.on('error', (error) => {
  69         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error)
  70       })
  71       ws.on('close', (code, reason) => {
  72         logger.debug(
  73           `${this.logPrefix(
  74             moduleName,
  75             'start.ws.onclose'
  76           )} WebSocket closed: '${getWebSocketCloseEventStatusString(
  77             code
  78           )}' - '${reason.toString()}'`
  79         )
  80       })
  81     })
  82     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, _head: Buffer) => {
  83       if (req.headers.connection !== 'Upgrade' || req.headers.upgrade !== 'websocket') {
  84         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`)
  85         socket.destroy()
  86       }
  87     })
  88     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  89       this.authenticate(req, (err) => {
  90         if (err != null) {
  91           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`)
  92           socket.destroy()
  93           return
  94         }
  95         try {
  96           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
  97             this.webSocketServer.emit('connection', ws, req)
  98           })
  99         } catch (error) {
 100           logger.error(
 101             `${this.logPrefix(
 102               moduleName,
 103               'start.httpServer.on.upgrade'
 104             )} Error at handling connection upgrade:`,
 105             error
 106           )
 107         }
 108       })
 109     })
 110     this.startHttpServer()
 111   }
 112
 113   public sendRequest (request: ProtocolRequest): void {
 114     this.broadcastToClients(JSON.stringify(request))
 115   }
 116
 117   public sendResponse (response: ProtocolResponse): void {
 118     const responseId = response[0]
 119     try {
 120       if (this.hasResponseHandler(responseId)) {
 121         const ws = this.responseHandlers.get(responseId) as WebSocket
 122         if (ws.readyState === WebSocket.OPEN) {
 123           ws.send(JSON.stringify(response))
 124         } else {
 125           logger.error(
 126             `${this.logPrefix(
 127               moduleName,
 128               'sendResponse'
 129             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 130               ws.readyState
 131             }`
 132           )
 133         }
 134       } else {
 135         logger.error(
 136           `${this.logPrefix(
 137             moduleName,
 138             'sendResponse'
 139           )} Response for unknown request id: ${responseId}`
 140         )
 141       }
 142     } catch (error) {
 143       logger.error(
 144         `${this.logPrefix(
 145           moduleName,
 146           'sendResponse'
 147         )} Error at sending response id '${responseId}':`,
 148         error
 149       )
 150     } finally {
 151       this.responseHandlers.delete(responseId)
 152     }
 153   }
 154
 155   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 156     const logMsgPrefix =
 157       prefixSuffix != null ? `UI WebSocket Server ${prefixSuffix}` : 'UI WebSocket Server'
 158     const logMsg =
 159       isNotEmptyString(modName) && isNotEmptyString(methodName)
 160         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 161         : ` ${logMsgPrefix} |`
 162     return logPrefix(logMsg)
 163   }
 164
 165   private broadcastToClients (message: string): void {
 166     for (const client of this.webSocketServer.clients) {
 167       if (client.readyState === WebSocket.OPEN) {
 168         client.send(message)
 169       }
 170     }
 171   }
 172
 173   private validateRawDataRequest (rawData: RawData): ProtocolRequest | false {
 174     // logger.debug(
 175     //   `${this.logPrefix(
 176     //     moduleName,
 177     //     'validateRawDataRequest'
 178     //     // eslint-disable-next-line @typescript-eslint/no-base-to-string
 179     //   )} Raw data received in string format: ${rawData.toString()}`
 180     // )
 181
 182     // eslint-disable-next-line @typescript-eslint/no-base-to-string
 183     const request = JSON.parse(rawData.toString()) as ProtocolRequest
 184
 185     if (!Array.isArray(request)) {
 186       logger.error(
 187         `${this.logPrefix(
 188           moduleName,
 189           'validateRawDataRequest'
 190         )} UI protocol request is not an array:`,
 191         request
 192       )
 193       return false
 194     }
 195
 196     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 197     if (request.length !== 3) {
 198       logger.error(
 199         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 200         request
 201       )
 202       return false
 203     }
 204
 205     if (!validateUUID(request[0])) {
 206       logger.error(
 207         `${this.logPrefix(
 208           moduleName,
 209           'validateRawDataRequest'
 210         )} UI protocol request UUID field is invalid:`,
 211         request
 212       )
 213       return false
 214     }
 215
 216     return request
 217   }
 218 }