@mikkel-ol/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;

  // @todo: Once GET is working, add support for all HTTP methods
  const requestOptions: http.RequestOptions = {
    hostname: "localhost",
    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);
      });
    },
  );

  // Send the request body if its not empty
  if (forwardedRequestMessage.body !== "") {
    const requestBody: Buffer = Buffer.from(
      forwardedRequestMessage.body,
      "base64",
    );
    request.write(requestBody);
  }

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

  request.end();
}