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tailhook / rotor

The mio-based framework for rust for doing I/O in simple and composable way (ABANDONED)
MIT License
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Deferring work to another protocol #18

Closed IlyaSkriblovsky closed 8 years ago

IlyaSkriblovsky commented 8 years ago

Sorry in advance if I'm asking a dumb question.

How it will look like if I need to query database to serve HTTP request by rotor-based HTTP server (supposing we have rotor-based DB driver)? I've studies all the examples and most of API docs, but still can't figure out what is the right way to defer some work to another protocol and be notified asynchronously when it is done (possibly with some response payload).

tailhook commented 8 years ago

Basically you create a Notifier object with a scope.notifier(). This is the object that may be used to wakeup a state machine (in context of which you have called scope). Then you must put it either to a shared location or to another state machine directly.

When you have a notifier, you can call wakeup() on it, and the wakeup method of the corresponding state machine will be called on the next loop iteration.

Let me illustrate with some code. Here we crate a state machine for a connection, and put a notifier of it to a shared location (A Schedule object). Then we can tweak settings in a shared state, which notifies connection's state machine. That in turn ends up in this wakeup code, and determines when to start a next http request.

Let me know if you need more help.

IlyaSkriblovsky commented 8 years ago

Thanks, I will study your code