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.writeHead(this.responseStatusToStatusCode(payload.status), {
  46           'Content-Type': 'application/json',
  47         });
  48         res.end(JSON.stringify(payload));
  49         this.responseHandlers.delete(uuid);
  50       } else {
  51         logger.error(
  52           `${this.logPrefix(moduleName, 'sendResponse')} Response for unknown request id: ${uuid}`
  53         );
  54       }
  55     } catch (error) {
  56       logger.error(
  57         `${this.logPrefix(moduleName, 'sendResponse')} Error at sending response id '${uuid}':`,
  58         error
  59       );
  60     }
  61   }
  62
  63   public logPrefix(modName?: string, methodName?: string, prefixSuffix?: string): string {
  64     const logMsgPrefix = prefixSuffix ? `UI HTTP Server ${prefixSuffix}` : 'UI HTTP Server';
  65     const logMsg =
  66       modName && methodName ? ` ${logMsgPrefix} | ${modName}.${methodName}:` : ` ${logMsgPrefix} |`;
  67     return Utils.logPrefix(logMsg);
  68   }
  69
  70   private requestListener(req: IncomingMessage, res: ServerResponse): void {
  71     this.authenticate(req, (err) => {
  72       if (err) {
  73         res.setHeader('Content-Type', 'text/plain');
  74         res.setHeader('WWW-Authenticate', 'Basic realm=users');
  75         res.writeHead(StatusCodes.UNAUTHORIZED);
  76         res.end(`${StatusCodes.UNAUTHORIZED} Unauthorized`);
  77         req.destroy();
  78         res.destroy();
  79       }
  80     });
  81     // Expected request URL pathname: /ui/:version/:procedureName
  82     const [protocol, version, procedureName] = req.url?.split('/').slice(1) as [
  83       Protocol,
  84       ProtocolVersion,
  85       ProcedureName
  86     ];
  87     const uuid = Utils.generateUUID();
  88     this.responseHandlers.set(uuid, res);
  89     try {
  90       if (UIServiceUtils.isProtocolAndVersionSupported(protocol, version) === false) {
  91         throw new BaseError(`Unsupported UI protocol version: '/${protocol}/${version}'`);
  92       }
  93       this.registerProtocolVersionUIService(version);
  94       req.on('error', (error) => {
  95         logger.error(
  96           `${this.logPrefix(moduleName, 'requestListener.req.onerror')} Error on HTTP request:`,
  97           error
  98         );
  99       });
 100       if (req.method === 'POST') {
 101         const bodyBuffer = [];
 102         req
 103           .on('data', (chunk) => {
 104             bodyBuffer.push(chunk);
 105           })
 106           .on('end', () => {
 107             const body = JSON.parse(Buffer.concat(bodyBuffer).toString()) as RequestPayload;
 108             this.uiServices
 109               .get(version)
 110               .requestHandler(this.buildProtocolRequest(uuid, procedureName, body ?? {}))
 111               .catch(() => {
 112                 /* Error caught by AbstractUIService */
 113               });
 114           });
 115       } else {
 116         throw new BaseError(`Unsupported HTTP method: '${req.method}'`);
 117       }
 118     } catch (error) {
 119       logger.error(
 120         `${this.logPrefix(moduleName, 'requestListener')} Handle HTTP request error:`,
 121         error
 122       );
 123       this.sendResponse(this.buildProtocolResponse(uuid, { status: ResponseStatus.FAILURE }));
 124     }
 125   }
 126
 127   private responseStatusToStatusCode(status: ResponseStatus): StatusCodes {
 128     switch (status) {
 129       case ResponseStatus.SUCCESS:
 130         return StatusCodes.OK;
 131       case ResponseStatus.FAILURE:
 132         return StatusCodes.BAD_REQUEST;
 133       default:
 134         return StatusCodes.INTERNAL_SERVER_ERROR;
 135     }
 136   }
 137 }