tcplexer/tcplexer.ts

#!/usr/bin/env -S deno run --allow-net --allow-env

import { iterateReader } from "https://deno.land/std@0.145.0/streams/conversion.ts";

const clients: Set<Deno.Conn> = new Set();

(async () => {
  try {
    const sourcePort = parseInt(Deno.env.get("SOURCE_PORT") || "") || 0;
    const sourceSockOpts = {
      port: sourcePort,
    };

    const sourceListener = Deno.listen(sourceSockOpts);
    console.info(
      "Listening for source connections on port",
      (sourceListener.addr as Deno.NetAddr).port,
    );
    for await (const source of sourceListener) {
      console.info("Source connected from", source.remoteAddr);
      for await (const packet of iterateReader(source)) {
        clients.forEach((client, _v2, _set) =>
          client.write(packet).catch(() => {
            console.log(`Client disconnected from`, client.remoteAddr);
            clients.delete(client);
          })
        );
      }
      console.info(`Source disconnected from`, source.remoteAddr);
    }
  } catch (err) {
    console.error("Error listening for source TCP connections:", err);
    Deno.exit(1);
  }
})();

(async () => {
  try {
    const clientPort = parseInt(Deno.env.get("CLIENT_PORT") || "") || 0;
    const clientSockOpts = {
      port: clientPort,
    };

    const clientsListener = Deno.listen(clientSockOpts);
    console.info(
      "Listening for client connections on port",
      (clientsListener.addr as Deno.NetAddr).port,
    );
    while (true) {
      try {
        const conn = await clientsListener.accept();
        console.log("Client connected from", conn.remoteAddr);
        clients.add(conn);
      } catch (err) {
        console.error("Error accepting client connection:", err);
      }
    }
  } catch (err) {
    console.error("Error listening for TCP connections on port 8081:", err);
  }
})();

/* stdin
(async () => {
  for await (const packet of iterateReader(Deno.stdin)) {
    clients.forEach((client, _v2, _set) =>
      client.write(packet).catch(() => {
        console.log(`Client disconnected from`, client.remoteAddr);
        clients.delete(client);
      })
    );
  }
})();
*/