src/charging-station/ui-server/UIHttpServer.ts

   1 import type { IncomingMessage, RequestListener, ServerResponse } from 'http';
   2
   3 import { StatusCodes } from 'http-status-codes';
   4
   5 import BaseError from '../../exception/BaseError';
   6 import type { UIServerConfiguration } from '../../types/ConfigurationData';
   7 import {
   8   ProcedureName,
   9   Protocol,
  10   ProtocolRequest,
  11   ProtocolResponse,
  12   ProtocolVersion,
  13   RequestPayload,
  14   ResponseStatus,
  15 } from '../../types/UIProtocol';
  16 import logger from '../../utils/Logger';
  17 import Utils from '../../utils/Utils';
  18 import { AbstractUIServer } from './AbstractUIServer';
  19 import { UIServiceUtils } from './ui-services/UIServiceUtils';
  20
  21 const moduleName = 'UIHttpServer';
  22
  23 export default class UIHttpServer extends AbstractUIServer {
  24   public constructor(protected readonly uiServerConfiguration: UIServerConfiguration) {
  25     super(uiServerConfiguration);
  26   }
  27
  28   public start(): void {
  29     this.httpServer.on('request', this.requestListener.bind(this) as RequestListener);
  30     if (this.httpServer.listening === false) {
  31       this.httpServer.listen(this.uiServerConfiguration.options);
  32     }
  33   }
  34
  35   // eslint-disable-next-line @typescript-eslint/no-unused-vars
  36   public sendRequest(request: ProtocolRequest): void {
  37     // This is intentionally left blank
  38   }
  39
  40   public sendResponse(response: ProtocolResponse): void {
  41     const [uuid, payload] = response;
  42     try {
  43       if (this.responseHandlers.has(uuid) === true) {
  44         const res = this.responseHandlers.get(uuid) as ServerResponse;
  45         res
  46           .writeHead(this.responseStatusToStatusCode(payload.status), {
  47             'Content-Type': 'application/json',
  48           })
  49           .end(JSON.stringify(payload));
  50         this.responseHandlers.delete(uuid);
  51       } else {
  52         logger.error(
  53           `${this.logPrefix(moduleName, 'sendResponse')} Response for unknown request id: ${uuid}`
  54         );
  55       }
  56     } catch (error) {
  57       logger.error(
  58         `${this.logPrefix(moduleName, 'sendResponse')} Error at sending response id '${uuid}':`,
  59         error
  60       );
  61     }
  62   }
  63
  64   public logPrefix(modName?: string, methodName?: string, prefixSuffix?: string): string {
  65     const logMsgPrefix = prefixSuffix ? `UI HTTP Server ${prefixSuffix}` : 'UI HTTP Server';
  66     const logMsg =
  67       modName && methodName ? ` ${logMsgPrefix} | ${modName}.${methodName}:` : ` ${logMsgPrefix} |`;
  68     return Utils.logPrefix(logMsg);
  69   }
  70
  71   private requestListener(req: IncomingMessage, res: ServerResponse): void {
  72     this.authenticate(req, (err) => {
  73       if (err) {
  74         res
  75           .writeHead(StatusCodes.UNAUTHORIZED, {
  76             'Content-Type': 'text/plain',
  77             'WWW-Authenticate': 'Basic realm=users',
  78           })
  79           .end(`${StatusCodes.UNAUTHORIZED} Unauthorized`)
  80           .destroy();
  81         req.destroy();
  82       }
  83     });
  84     // Expected request URL pathname: /ui/:version/:procedureName
  85     const [protocol, version, procedureName] = req.url?.split('/').slice(1) as [
  86       Protocol,
  87       ProtocolVersion,
  88       ProcedureName
  89     ];
  90     const uuid = Utils.generateUUID();
  91     this.responseHandlers.set(uuid, res);
  92     try {
  93       if (UIServiceUtils.isProtocolAndVersionSupported(protocol, version) === false) {
  94         throw new BaseError(`Unsupported UI protocol version: '/${protocol}/${version}'`);
  95       }
  96       this.registerProtocolVersionUIService(version);
  97       req.on('error', (error) => {
  98         logger.error(
  99           `${this.logPrefix(moduleName, 'requestListener.req.onerror')} Error on HTTP request:`,
 100           error
 101         );
 102       });
 103       if (req.method === 'POST') {
 104         const bodyBuffer = [];
 105         req
 106           .on('data', (chunk) => {
 107             bodyBuffer.push(chunk);
 108           })
 109           .on('end', () => {
 110             const body = JSON.parse(Buffer.concat(bodyBuffer).toString()) as RequestPayload;
 111             this.uiServices
 112               .get(version)
 113               .requestHandler(this.buildProtocolRequest(uuid, procedureName, body ?? {}))
 114               .catch(() => {
 115                 /* Error caught by AbstractUIService */
 116               });
 117           });
 118       } else {
 119         throw new BaseError(`Unsupported HTTP method: '${req.method}'`);
 120       }
 121     } catch (error) {
 122       logger.error(
 123         `${this.logPrefix(moduleName, 'requestListener')} Handle HTTP request error:`,
 124         error
 125       );
 126       this.sendResponse(this.buildProtocolResponse(uuid, { status: ResponseStatus.FAILURE }));
 127     }
 128   }
 129
 130   private responseStatusToStatusCode(status: ResponseStatus): StatusCodes {
 131     switch (status) {
 132       case ResponseStatus.SUCCESS:
 133         return StatusCodes.OK;
 134       case ResponseStatus.FAILURE:
 135         return StatusCodes.BAD_REQUEST;
 136       default:
 137         return StatusCodes.INTERNAL_SERVER_ERROR;
 138     }
 139   }
 140 }