Most of the programming we do in Maya is about automation. There's little that can be accomplished with code that cannot otherwise be done by hand. We create code to run inside of Maya, during a user's session, to get them faster from point A to point B. We speed up what takes too long to be pleasant or practical.

In this chapter, though, we will do programming that isn't directly about speeding what a user normally does. We're going to develop a system that will allow us to control and automate Maya in arbitrary ways. The controlling code will not run inside of Maya, but in its own Python process. We will not control Maya using an application-specific feature like the command port, but a general request-reply system that could be at home in another application. Automating Maya from the outside will open up totally new possibilities for designing tools and pipelines.

We will start by learning about the request-reply pattern for client and server...