Create new EventDispatcher to move user-provided callback execution out of the main thread - #403
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Coverage Report for CI Build 30923141826Coverage increased (+0.3%) to 93.678%Details
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we'll cross that bridge when we get to that river
I feel like this is self explanatory, happy to reconsider, though.
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Aug 5, 2026
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On second thought, this sentinel is not super very idiomatic.
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Replaced by a class-based one.
Using an instance of object was a bit awkward
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August 5, 2026 12:40
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Summary
The pull request introduces the implementation of
EventDispatcher. Its goal is to move all event-and-callback-related code to the same file. At the same time, theEventDispatcheris based on threads: the "callers" of the dispatcher will useemit_eventto queue an event, and a worker thread managed by the dispatcher will drain the queue.In this pull request, the Dispatcher is not yet wired to anyone.
Reason for these changes
This is the initial step towards solving two problems:
is_enabledindefinitely; andUnleashClient(i.e.AsyncUnleashClient) will also support sending events to a callbackBy introducing a single class that deals with event-sending as a whole, code will be shared and we ensure we don't run it in the hot path anymore (as long as we publish events through the
EventDispatcher).Tricky parts when reviewing
Threads and locks
EventDispatcherdeals with locks and threads, which is always fun. Variables like_closed, as well as the two centinels (_SHUTDOWNand_FlushMarker) help manage the synchronization of operations:close()Backpressure
I discarded the option of adding a timeout or a number of retries to a user's callback. I'm happy to revisit the decision.