Communicating with a Python service.

Question

Problem:

I have a python script that I have running as a service. It's a subclass of the win32 class win32serviceutil.ServiceFramework. I want a simple straightforward way of sending arbitrary commands to it via the command line.

What I've looked at:

It looks like the standard way of controlling the service once it's started is by using another program and sending it command signals, but I need to be able to send a short string to it as well as an argument. It looks like using a NamedPipe might be a good idea, but it's really too complex for what I wanted to do, is there any other simpler way?

Answer 1

Not really.

You have many, many ways to do "Interprocess Communication" (IPC) in Python.

• Sockets

• Named Pipes (see http://developers.sun.com/solaris/articles/named_pipes.html) -- it involves a little bit of OS magic to create, but then it's just a file that you read and write.

• Shared Memory (see http://en.wikipedia.org/wiki/Shared_memory) -- this also involves a fair amount of OS-level magic.

• Semphores and Locks; files with locks can work well for IPC.

• Higher-level protocols built on sockets...

  • HTTP; this is what WSGI is all about.

  • FTP

  • etc.

A common solution is to use HTTP and define "RESTful" commands. Your service listens on port 80 for HTTP requests that contain arguments and parameters. Look at wsgiref for more information on this.