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 {
   9   getProtocolAndVersion,
  10   handleProtocols,
  11   isProtocolAndVersionSupported
  12 } from './UIServerUtils.js'
  13 import {
  14   type ProtocolRequest,
  15   type ProtocolResponse,
  16   type UIServerConfiguration,
  17   WebSocketCloseEventStatusCode
  18 } from '../../types/index.js'
  19 import {
  20   Constants,
  21   JSONStringifyWithMapSupport,
  22   getWebSocketCloseEventStatusString,
  23   isNotEmptyString,
  24   logPrefix,
  25   logger,
  26   validateUUID
  27 } from '../../utils/index.js'
  28
  29 const moduleName = 'UIWebSocketServer'
  30
  31 export class UIWebSocketServer extends AbstractUIServer {
  32   private readonly webSocketServer: WebSocketServer
  33
  34   public constructor (protected readonly uiServerConfiguration: UIServerConfiguration) {
  35     super(uiServerConfiguration)
  36     this.webSocketServer = new WebSocketServer({
  37       handleProtocols,
  38       noServer: true
  39     })
  40   }
  41
  42   public start (): void {
  43     this.webSocketServer.on('connection', (ws: WebSocket, _req: IncomingMessage): void => {
  44       if (!isProtocolAndVersionSupported(ws.protocol)) {
  45         logger.error(
  46           `${this.logPrefix(
  47             moduleName,
  48             'start.server.onconnection'
  49           )} Unsupported UI protocol version: '${ws.protocol}'`
  50         )
  51         ws.close(WebSocketCloseEventStatusCode.CLOSE_PROTOCOL_ERROR)
  52       }
  53       const [, version] = getProtocolAndVersion(ws.protocol)
  54       this.registerProtocolVersionUIService(version)
  55       ws.on('message', rawData => {
  56         const request = this.validateRawDataRequest(rawData)
  57         if (request === false) {
  58           ws.close(WebSocketCloseEventStatusCode.CLOSE_INVALID_PAYLOAD)
  59           return
  60         }
  61         const [requestId] = request
  62         this.responseHandlers.set(requestId, ws)
  63         this.uiServices
  64           .get(version)
  65           ?.requestHandler(request)
  66           .then((protocolResponse?: ProtocolResponse) => {
  67             if (protocolResponse != null) {
  68               this.sendResponse(protocolResponse)
  69             }
  70           })
  71           .catch(Constants.EMPTY_FUNCTION)
  72       })
  73       ws.on('error', error => {
  74         logger.error(`${this.logPrefix(moduleName, 'start.ws.onerror')} WebSocket error:`, error)
  75       })
  76       ws.on('close', (code, reason) => {
  77         logger.debug(
  78           `${this.logPrefix(
  79             moduleName,
  80             'start.ws.onclose'
  81           )} WebSocket closed: '${getWebSocketCloseEventStatusString(
  82             code
  83           )}' - '${reason.toString()}'`
  84         )
  85       })
  86     })
  87     this.httpServer.on('connect', (req: IncomingMessage, socket: Duplex, _head: Buffer) => {
  88       if (req.headers.connection !== 'Upgrade' || req.headers.upgrade !== 'websocket') {
  89         socket.write(`HTTP/1.1 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`)
  90         socket.destroy()
  91       }
  92     })
  93     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  94       this.authenticate(req, err => {
  95         if (err != null) {
  96           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`)
  97           socket.destroy()
  98           return
  99         }
 100         try {
 101           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
 102             this.webSocketServer.emit('connection', ws, req)
 103           })
 104         } catch (error) {
 105           logger.error(
 106             `${this.logPrefix(
 107               moduleName,
 108               'start.httpServer.on.upgrade'
 109             )} Error at handling connection upgrade:`,
 110             error
 111           )
 112         }
 113       })
 114     })
 115     this.startHttpServer()
 116   }
 117
 118   public sendRequest (request: ProtocolRequest): void {
 119     this.broadcastToClients(JSON.stringify(request))
 120   }
 121
 122   public sendResponse (response: ProtocolResponse): void {
 123     const responseId = response[0]
 124     try {
 125       if (this.hasResponseHandler(responseId)) {
 126         const ws = this.responseHandlers.get(responseId) as WebSocket
 127         if (ws.readyState === WebSocket.OPEN) {
 128           ws.send(JSONStringifyWithMapSupport(response))
 129         } else {
 130           logger.error(
 131             `${this.logPrefix(
 132               moduleName,
 133               'sendResponse'
 134             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 135               ws.readyState
 136             }`
 137           )
 138         }
 139       } else {
 140         logger.error(
 141           `${this.logPrefix(
 142             moduleName,
 143             'sendResponse'
 144           )} Response for unknown request id: ${responseId}`
 145         )
 146       }
 147     } catch (error) {
 148       logger.error(
 149         `${this.logPrefix(
 150           moduleName,
 151           'sendResponse'
 152         )} Error at sending response id '${responseId}':`,
 153         error
 154       )
 155     } finally {
 156       this.responseHandlers.delete(responseId)
 157     }
 158   }
 159
 160   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 161     const logMsgPrefix =
 162       prefixSuffix != null ? `UI WebSocket Server ${prefixSuffix}` : 'UI WebSocket Server'
 163     const logMsg =
 164       isNotEmptyString(modName) && isNotEmptyString(methodName)
 165         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 166         : ` ${logMsgPrefix} |`
 167     return logPrefix(logMsg)
 168   }
 169
 170   private broadcastToClients (message: string): void {
 171     for (const client of this.webSocketServer.clients) {
 172       if (client.readyState === WebSocket.OPEN) {
 173         client.send(message)
 174       }
 175     }
 176   }
 177
 178   private validateRawDataRequest (rawData: RawData): ProtocolRequest | false {
 179     // logger.debug(
 180     //   `${this.logPrefix(
 181     //     moduleName,
 182     //     'validateRawDataRequest'
 183     //     // eslint-disable-next-line @typescript-eslint/no-base-to-string
 184     //   )} Raw data received in string format: ${rawData.toString()}`
 185     // )
 186
 187     let request: ProtocolRequest
 188     try {
 189       // eslint-disable-next-line @typescript-eslint/no-base-to-string
 190       request = JSON.parse(rawData.toString()) as ProtocolRequest
 191     } catch (error) {
 192       logger.error(
 193         `${this.logPrefix(
 194           moduleName,
 195           'validateRawDataRequest'
 196           // eslint-disable-next-line @typescript-eslint/no-base-to-string
 197         )} UI protocol request is not valid JSON: ${rawData.toString()}`
 198       )
 199       return false
 200     }
 201
 202     if (!Array.isArray(request)) {
 203       logger.error(
 204         `${this.logPrefix(
 205           moduleName,
 206           'validateRawDataRequest'
 207         )} UI protocol request is not an array:`,
 208         request
 209       )
 210       return false
 211     }
 212
 213     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 214     if (request.length !== 3) {
 215       logger.error(
 216         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 217         request
 218       )
 219       return false
 220     }
 221
 222     if (!validateUUID(request[0])) {
 223       logger.error(
 224         `${this.logPrefix(
 225           moduleName,
 226           'validateRawDataRequest'
 227         )} UI protocol request UUID field is invalid:`,
 228         request
 229       )
 230       return false
 231     }
 232
 233     return request
 234   }
 235 }