@thgh/tunnelmole/src/message-handlers/forwarded-request.ts

Tunnelmole, an open source ngrok alternative. Instant public URLs for any http/https based application. Available as a command line application or as an NPM dependency for your code. Stable and maintained. Good test coverage. Works behind firewalls

import HostipWebSocket from "../websocket/host-ip-websocket.js"
import ForwardedRequestMessage from "../messages/forwarded-request-message.js"
import http from 'http';
import ForwardedResponseMessage from "../messages/forwarded-response-message.js"
import { forwardedResponse } from "../messages/types.js"
import log from "../logging/log.js"
import { Options } from "../options.js";

export default async function forwardedRequest(forwardedRequestMessage: ForwardedRequestMessage, websocket: HostipWebSocket, options : Options) {
    const port = options.port;
    const { requestId, url, headers } = forwardedRequestMessage;

    // Prevent issue with gzip encoding
    delete headers['Accept-Encoding']
    delete headers['accept-encoding']

    // @todo: Once GET is working, add support for all HTTP methods
    const requestOptions : http.RequestOptions = {
        hostname: '127.0.0.1',
        method: forwardedRequestMessage.method,
        port: port,
        path: url,
        headers
    };

    const request = http.request(requestOptions, (response : http.IncomingMessage) => {
        let responseBody : Buffer;
        response.on('data', (chunk: Buffer) => {
            if (typeof responseBody === 'undefined') {
                responseBody = chunk;
            } else {
                responseBody = Buffer.concat([responseBody, chunk]);
            }
        });

        /**
         * If you see this callback being called more than once, this is probably normal especially if a browser initiated the request
         * Most browsers will make more than one request, for example an extra one for favicon.ico
         */
        response.on('end', () => {
            //@ts-ignore
            const forwardedResponseMessage : ForwardedResponseMessage = {
                type: forwardedResponse,
                requestId,
                statusCode: response.statusCode,
                url,
                headers: response.headers,
                body: ''
            }

            if (Buffer.isBuffer(responseBody)) {
                forwardedResponseMessage.body = responseBody.toString('base64');
            }

            websocket.sendMessage(forwardedResponseMessage);
        })
    });

    const requestBody : Buffer = Buffer.from(forwardedRequestMessage.body, 'base64');
    request.write(requestBody);

    request.on('error', (error : any) => {
        log(error);
    });

    request.end();
}