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';
   6 import {
   7   type ProcedureName,
   8   type Protocol,
   9   type ProtocolRequest,
  10   type ProtocolResponse,
  11   type ProtocolVersion,
  12   type RequestPayload,
  13   ResponseStatus,
  14   type UIServerConfiguration,
  15 } from '../../types';
  16 import { logger } from '../../utils/Logger';
  17 import { Utils } from '../../utils/Utils';
  18 import { AbstractUIServer, UIServerUtils } from '../internal';
  19
  20 const moduleName = 'UIHttpServer';
  21
  22 export class UIHttpServer extends AbstractUIServer {
  23   public constructor(protected readonly uiServerConfiguration: UIServerConfiguration) {
  24     super(uiServerConfiguration);
  25   }
  26
  27   public start(): void {
  28     this.httpServer.on('request', this.requestListener.bind(this) as RequestListener);
  29     this.startHttpServer();
  30   }
  31
  32   // eslint-disable-next-line @typescript-eslint/no-unused-vars
  33   public sendRequest(request: ProtocolRequest): void {
  34     // This is intentionally left blank
  35   }
  36
  37   public sendResponse(response: ProtocolResponse): void {
  38     const [uuid, payload] = response;
  39     try {
  40       if (this.responseHandlers.has(uuid) === true) {
  41         const res = this.responseHandlers.get(uuid) as ServerResponse;
  42         res
  43           .writeHead(this.responseStatusToStatusCode(payload.status), {
  44             'Content-Type': 'application/json',
  45           })
  46           .end(JSON.stringify(payload));
  47       } else {
  48         logger.error(
  49           `${this.logPrefix(moduleName, 'sendResponse')} Response for unknown request id: ${uuid}`
  50         );
  51       }
  52     } catch (error) {
  53       logger.error(
  54         `${this.logPrefix(moduleName, 'sendResponse')} Error at sending response id '${uuid}':`,
  55         error
  56       );
  57     } finally {
  58       this.responseHandlers.delete(uuid);
  59     }
  60   }
  61
  62   public logPrefix = (modName?: string, methodName?: string, prefixSuffix?: string): string => {
  63     const logMsgPrefix = prefixSuffix ? `UI HTTP Server ${prefixSuffix}` : 'UI HTTP Server';
  64     const logMsg =
  65       Utils.isNotEmptyString(modName) && Utils.isNotEmptyString(methodName)
  66         ? ` ${logMsgPrefix} | ${modName}.${methodName}:`
  67         : ` ${logMsgPrefix} |`;
  68     return Utils.logPrefix(logMsg);
  69   };
  70
  71   private requestListener(req: IncomingMessage, res: ServerResponse): void {
  72     this.authenticate(req, (err) => {
  73       if (err) {
  74         res
  75           .writeHead(StatusCodes.UNAUTHORIZED, {
  76             'Content-Type': 'text/plain',
  77             'WWW-Authenticate': 'Basic realm=users',
  78           })
  79           .end(`${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       const fullProtocol = `${protocol}${version}`;
  94       if (UIServerUtils.isProtocolAndVersionSupported(fullProtocol) === false) {
  95         throw new BaseError(`Unsupported UI protocol version: '${fullProtocol}'`);
  96       }
  97       this.registerProtocolVersionUIService(version);
  98       req.on('error', (error) => {
  99         logger.error(
 100           `${this.logPrefix(moduleName, 'requestListener.req.onerror')} Error on HTTP request:`,
 101           error
 102         );
 103       });
 104       if (req.method === 'POST') {
 105         const bodyBuffer = [];
 106         req
 107           .on('data', (chunk) => {
 108             bodyBuffer.push(chunk);
 109           })
 110           .on('end', () => {
 111             const body = JSON.parse(Buffer.concat(bodyBuffer).toString()) as RequestPayload;
 112             this.uiServices
 113               .get(version)
 114               ?.requestHandler(this.buildProtocolRequest(uuid, procedureName, body ?? {}))
 115               .catch(() => {
 116                 /* Error caught by AbstractUIService */
 117               });
 118           });
 119       } else {
 120         throw new BaseError(`Unsupported HTTP method: '${req.method}'`);
 121       }
 122     } catch (error) {
 123       logger.error(
 124         `${this.logPrefix(moduleName, 'requestListener')} Handle HTTP request error:`,
 125         error
 126       );
 127       this.sendResponse(this.buildProtocolResponse(uuid, { status: ResponseStatus.FAILURE }));
 128     }
 129   }
 130
 131   private responseStatusToStatusCode(status: ResponseStatus): StatusCodes {
 132     switch (status) {
 133       case ResponseStatus.SUCCESS:
 134         return StatusCodes.OK;
 135       case ResponseStatus.FAILURE:
 136         return StatusCodes.BAD_REQUEST;
 137       default:
 138         return StatusCodes.INTERNAL_SERVER_ERROR;
 139     }
 140   }
 141 }