Execute a few commands via C# console-app

Question

I'm new to C# (and development in general). I need to write a method in C# that will execute following via console: - install Newman; - execute postman Run.

I've created a method as below (I tried 2 options: ReadToEnd and WaitForExit), but it seems to stuck at each of these steps.

Any help how to make this to execute both commands in sequence (1st needs to finish before 2nd start) and exit after 2nd command executed fully?

Thanks in advance.

    public string Runner ()
    {
        string readOutput = null;
        var psiNpm = new ProcessStartInfo
        {
            FileName = "cmd",
            RedirectStandardOutput = true,
            RedirectStandardInput = true,
            UseShellExecute = false
        };
        var pNpmRun = Process.Start(psiNpm);
        pNpmRun.StandardInput.WriteLine($"npm install -g newman");
        pNpmRun.WaitForExit();
        //pNpmRun.StandardOutput.ReadToEnd();
        pNpmRun.StandardInput.WriteLine($"newman run " +
            $"\"C:\\Postman\\Test.postman.json\" " +
            $"--folder \"TestSearch\" " +
            $"--environment \"C:\\Postman\\postman_environment.json\" " +
            $"--disable-unicode");
        pNpmRun.StandardOutput.ReadToEnd();
        pNpmRun.WaitForExit();
        return readOutput = pNpmRun.StandardOutput.ReadLine();
    }

Answer 1

Try writing an exit command to your cmd input stream.

The issue, is the commands you sent (npm, newman) are executing, then control is returning to the shell (cmd), which is then waiting for more user input to be sent. You need to tell it to quit by sending "exit". You should only have 1 WaitForExit call. The WaitForExit is waiting for the cmd process to exit, not the individual commands you send to it.

Next, you should move ReadToEnd after the process has exited (after WaitForExit). Here is a question concering why: ReadToEnd from std output of process and waitforexit

So, something like this:

public string Runner ()
    {
        var psiNpm = new ProcessStartInfo
        {
            FileName = "cmd",
            RedirectStandardOutput = true,
            RedirectStandardInput = true,
            UseShellExecute = false
        };
        var pNpmRun = Process.Start(psiNpm);
        pNpmRun.StandardInput.WriteLine("npm install -g newman");
        pNpmRun.StandardInput.WriteLine("newman run " +
            "\"C:\\Postman\\Test.postman.json\" " +
            "--folder \"TestSearch\" " +
            "--environment \"C:\\Postman\\postman_environment.json\" " +
            "--disable-unicode");
        pNpmRun.StandardInput.WriteLine("exit");

        pNpmRun.WaitForExit();
        return pNpmRun.StandardOutput.ReadToEnd();

You might also consider adding a timeout to the WaitForExit. If these cmds get stuck for some reason your calling process is also going to get stuck waiting for them to complete. Usually best to eventually fail than have a bunch of hung processes. You could then kill the process if the timeout expires.

  var tenMin = 10 * 60 * 1000;
  if(pNpmRun.WaitForExit(tenMin)) {
    return pNpmRun.StandardOutput.ReadToEnd();
  } else {
    pNpmRun.Kill();
    throw new TimeoutException("Command didn't complete in 10 minute timeout");
  }