example single command terminal exec using streams

session.ts

import { Readable, Writable } from "node:stream";
import { spawn } from "node:child_process";

export const execCommand = async (cmd: string) => {
  const ps = spawn("sh", { env: process.env });

  const data: string[] = [];

  const outputStream = new Writable({
    write(chunk, encoding, callback) {
      data.push(chunk.toString(encoding));
      callback();
    },
  });
  ps.stdout?.pipe(outputStream);
  ps.stderr?.pipe(outputStream);

  const inputStream = new Readable({
    async read() {
      this.push(cmd);
      this.push(null);
      this.push("exit");
    },
  });
  inputStream.pipe(ps.stdin);

  await new Promise<string>((resolve) =>
    ps.on("close", () => resolve(data.join("\n")))
  );
};