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 { AbstractUIServer } from './AbstractUIServer';
   6 import { UIServerUtils } from './UIServerUtils';
   7 import { BaseError } from '../../exception';
   8 import {
   9   type ProcedureName,
  10   type Protocol,
  11   type ProtocolRequest,
  12   type ProtocolResponse,
  13   type ProtocolVersion,
  14   type RequestPayload,
  15   ResponseStatus,
  16   type UIServerConfiguration,
  17 } from '../../types';
  18 import { logger } from '../../utils/Logger';
  19 import { Utils } from '../../utils/Utils';
  20
  21 const moduleName = 'UIHttpServer';
  22
  23 export 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     this.startHttpServer();
  31   }
  32
  33   // eslint-disable-next-line @typescript-eslint/no-unused-vars
  34   public sendRequest(request: ProtocolRequest): void {
  35     // This is intentionally left blank
  36   }
  37
  38   public sendResponse(response: ProtocolResponse): void {
  39     const [uuid, payload] = response;
  40     try {
  41       if (this.responseHandlers.has(uuid) === true) {
  42         const res = this.responseHandlers.get(uuid) as ServerResponse;
  43         res
  44           .writeHead(this.responseStatusToStatusCode(payload.status), {
  45             'Content-Type': 'application/json',
  46           })
  47           .end(JSON.stringify(payload));
  48       } else {
  49         logger.error(
  50           `${this.logPrefix(moduleName, 'sendResponse')} Response for unknown request id: ${uuid}`
  51         );
  52       }
  53     } catch (error) {
  54       logger.error(
  55         `${this.logPrefix(moduleName, 'sendResponse')} Error at sending response id '${uuid}':`,
  56         error
  57       );
  58     } finally {
  59       this.responseHandlers.delete(uuid);
  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       Utils.isNotEmptyString(modName) && Utils.isNotEmptyString(methodName)
  67         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
  68         : ` ${logMsgPrefix} |`;
  69     return Utils.logPrefix(logMsg);
  70   };
  71
  72   private requestListener(req: IncomingMessage, res: ServerResponse): void {
  73     this.authenticate(req, (err) => {
  74       if (err) {
  75         res
  76           .writeHead(StatusCodes.UNAUTHORIZED, {
  77             'Content-Type': 'text/plain',
  78             'WWW-Authenticate': 'Basic realm=users',
  79           })
  80           .end(`${StatusCodes.UNAUTHORIZED} Unauthorized`)
  81           .destroy();
  82         req.destroy();
  83       }
  84     });
  85     // Expected request URL pathname: /ui/:version/:procedureName
  86     const [protocol, version, procedureName] = req.url?.split('/').slice(1) as [
  87       Protocol,
  88       ProtocolVersion,
  89       ProcedureName
  90     ];
  91     const uuid = Utils.generateUUID();
  92     this.responseHandlers.set(uuid, res);
  93     try {
  94       const fullProtocol = `${protocol}${version}`;
  95       if (UIServerUtils.isProtocolAndVersionSupported(fullProtocol) === false) {
  96         throw new BaseError(`Unsupported UI protocol version: '${fullProtocol}'`);
  97       }
  98       this.registerProtocolVersionUIService(version);
  99       req.on('error', (error) => {
 100         logger.error(
 101           `${this.logPrefix(moduleName, 'requestListener.req.onerror')} Error on HTTP request:`,
 102           error
 103         );
 104       });
 105       if (req.method === 'POST') {
 106         const bodyBuffer = [];
 107         req
 108           .on('data', (chunk) => {
 109             bodyBuffer.push(chunk);
 110           })
 111           .on('end', () => {
 112             const body = JSON.parse(Buffer.concat(bodyBuffer).toString()) as RequestPayload;
 113             this.uiServices
 114               .get(version)
 115               ?.requestHandler(this.buildProtocolRequest(uuid, procedureName, body ?? {}))
 116               .catch(() => {
 117                 /* Error caught by AbstractUIService */
 118               });
 119           });
 120       } else {
 121         throw new BaseError(`Unsupported HTTP method: '${req.method}'`);
 122       }
 123     } catch (error) {
 124       logger.error(
 125         `${this.logPrefix(moduleName, 'requestListener')} Handle HTTP request error:`,
 126         error
 127       );
 128       this.sendResponse(this.buildProtocolResponse(uuid, { status: ResponseStatus.FAILURE }));
 129     }
 130   }
 131
 132   private responseStatusToStatusCode(status: ResponseStatus): StatusCodes {
 133     switch (status) {
 134       case ResponseStatus.SUCCESS:
 135         return StatusCodes.OK;
 136       case ResponseStatus.FAILURE:
 137         return StatusCodes.BAD_REQUEST;
 138       default:
 139         return StatusCodes.INTERNAL_SERVER_ERROR;
 140     }
 141   }
 142 }