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 {
   8   type ProtocolRequest,
   9   type ProtocolResponse,
  10   type UIServerConfiguration,
  11   WebSocketCloseEventStatusCode
  12 } from '../../types/index.js'
  13 import {
  14   Constants,
  15   getWebSocketCloseEventStatusString,
  16   isNotEmptyString,
  17   JSONStringifyWithMapSupport,
  18   logger,
  19   logPrefix,
  20   validateUUID
  21 } from '../../utils/index.js'
  22 import { AbstractUIServer } from './AbstractUIServer.js'
  23 import {
  24   getProtocolAndVersion,
  25   handleProtocols,
  26   isProtocolAndVersionSupported
  27 } from './UIServerUtils.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 ${StatusCodes.BAD_REQUEST} Bad Request\r\n\r\n`)
  90         socket.destroy()
  91       }
  92     })
  93     this.httpServer.on('upgrade', (req: IncomingMessage, socket: Duplex, head: Buffer): void => {
  94       const onSocketError = (error: Error): void => {
  95         logger.error(
  96           `${this.logPrefix(
  97             moduleName,
  98             'start.httpServer.on.upgrade'
  99           )} Socket error at connection upgrade event handling:`,
 100           error
 101         )
 102       }
 103       socket.on('error', onSocketError)
 104       this.authenticate(req, err => {
 105         if (err != null) {
 106           socket.write(`HTTP/1.1 ${StatusCodes.UNAUTHORIZED} Unauthorized\r\n\r\n`)
 107           socket.destroy()
 108           return
 109         }
 110         try {
 111           this.webSocketServer.handleUpgrade(req, socket, head, (ws: WebSocket) => {
 112             this.webSocketServer.emit('connection', ws, req)
 113           })
 114         } catch (error) {
 115           logger.error(
 116             `${this.logPrefix(
 117               moduleName,
 118               'start.httpServer.on.upgrade'
 119             )} Error at connection upgrade event handling:`,
 120             error
 121           )
 122         }
 123       })
 124       socket.removeListener('error', onSocketError)
 125     })
 126     this.startHttpServer()
 127   }
 128
 129   public sendRequest (request: ProtocolRequest): void {
 130     this.broadcastToClients(JSON.stringify(request))
 131   }
 132
 133   public sendResponse (response: ProtocolResponse): void {
 134     const responseId = response[0]
 135     try {
 136       if (this.hasResponseHandler(responseId)) {
 137         const ws = this.responseHandlers.get(responseId) as WebSocket
 138         if (ws.readyState === WebSocket.OPEN) {
 139           ws.send(JSONStringifyWithMapSupport(response))
 140         } else {
 141           logger.error(
 142             `${this.logPrefix(
 143               moduleName,
 144               'sendResponse'
 145             )} Error at sending response id '${responseId}', WebSocket is not open: ${
 146               ws.readyState
 147             }`
 148           )
 149         }
 150       } else {
 151         logger.error(
 152           `${this.logPrefix(
 153             moduleName,
 154             'sendResponse'
 155           )} Response for unknown request id: ${responseId}`
 156         )
 157       }
 158     } catch (error) {
 159       logger.error(
 160         `${this.logPrefix(
 161           moduleName,
 162           'sendResponse'
 163         )} Error at sending response id '${responseId}':`,
 164         error
 165       )
 166     } finally {
 167       this.responseHandlers.delete(responseId)
 168     }
 169   }
 170
 171   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
 172     const logMsgPrefix =
 173       prefixSuffix != null ? `UI WebSocket Server ${prefixSuffix}` : 'UI WebSocket Server'
 174     const logMsg =
 175       isNotEmptyString(modName) && isNotEmptyString(methodName)
 176         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
 177         : ` ${logMsgPrefix} |`
 178     return logPrefix(logMsg)
 179   }
 180
 181   private broadcastToClients (message: string): void {
 182     for (const client of this.webSocketServer.clients) {
 183       if (client.readyState === WebSocket.OPEN) {
 184         client.send(message)
 185       }
 186     }
 187   }
 188
 189   private validateRawDataRequest (rawData: RawData): ProtocolRequest | false {
 190     // logger.debug(
 191     //   `${this.logPrefix(
 192     //     moduleName,
 193     //     'validateRawDataRequest'
 194     //     // eslint-disable-next-line @typescript-eslint/no-base-to-string
 195     //   )} Raw data received in string format: ${rawData.toString()}`
 196     // )
 197
 198     let request: ProtocolRequest
 199     try {
 200       // eslint-disable-next-line @typescript-eslint/no-base-to-string
 201       request = JSON.parse(rawData.toString()) as ProtocolRequest
 202     } catch (error) {
 203       logger.error(
 204         `${this.logPrefix(
 205           moduleName,
 206           'validateRawDataRequest'
 207           // eslint-disable-next-line @typescript-eslint/no-base-to-string
 208         )} UI protocol request is not valid JSON: ${rawData.toString()}`
 209       )
 210       return false
 211     }
 212
 213     if (!Array.isArray(request)) {
 214       logger.error(
 215         `${this.logPrefix(
 216           moduleName,
 217           'validateRawDataRequest'
 218         )} UI protocol request is not an array:`,
 219         request
 220       )
 221       return false
 222     }
 223
 224     // eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
 225     if (request.length !== 3) {
 226       logger.error(
 227         `${this.logPrefix(moduleName, 'validateRawDataRequest')} UI protocol request is malformed:`,
 228         request
 229       )
 230       return false
 231     }
 232
 233     if (!validateUUID(request[0])) {
 234       logger.error(
 235         `${this.logPrefix(
 236           moduleName,
 237           'validateRawDataRequest'
 238         )} UI protocol request UUID field is invalid:`,
 239         request
 240       )
 241       return false
 242     }
 243
 244     return request
 245   }
 246 }