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coproc provides building blocks for running stateful, concurrent, and specialized worker processes that require back-and-forth communication. The name comes from the combination of "cooperative" and "process" - coproc makes it easier to create specialized processes that cooperate to solve a single task.


Explanatory diagram.

  • In coproc, we refer to the main process of a Python script as the host, and any daeomon processes it creates as worker processes.

  • The host maintains a WorkerResource object which includes the child process and a pipe for transmitting information, as well as a PriorityMessenger that manages communications across the channel.

  • WorkerProcess exists on the worker side, and maintains the processes state and main event loop. The worker process also includes a PriorityMessenger that is used to communicate with the host process.

The following diagram shows how the host and worker work together: they each maintain PriorityMessenger objects that support multi-channel priority messaging designs.