0c6f1c9c3a
- consistent renaming - React -> Event - ReactorEvent -> EventHandler - NewReactorEngine -> New - async ReactorEngine main loop with select on main eventChannel and quit channel - ReactorEngine main loop control with Start() Stop() Flush() - ReactorEngine.dispatch - use sync.RWMutex - delete eventHandler if subscribed channels go to 0
41 lines
1.3 KiB
Markdown
41 lines
1.3 KiB
Markdown
# ethreact
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ethereum event reactor. Component of the ethereum stack.
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various events like state change on an account or new block found are broadcast to subscribers.
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Broadcasting to subscribers is running on its own routine and globally order preserving.
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## Clients
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### subscribe
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eventChannel := make(chan ethreact.Event)
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reactor.Subscribe(event, eventChannel)
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The same channel can be subscribed to multiple events but only once for each event. In order to allow order of events to be preserved, broadcast of events is synchronous within the main broadcast loop. Therefore any blocking subscriber channels will be skipped, i.e. missing broadcasting events while they are blocked.
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### unsubscribe
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reactor.Unsubscribe(event, eventChannel)
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### Processing events
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event.Resource is of type interface{}. The actual type of event.Resource depends on event.Name and may need to be cast for processing.
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var event ethreact.Event
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for {
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select {
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case event = <-eventChannel:
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processTransaction(event.Resource.(Transaction))
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}
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}
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## Broadcast
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reactor := ethreact.New()
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reactor.Start()
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reactor.Post(name, resource)
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reactor.Flush() // wait till all broadcast messages are dispatched
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reactor.Stop() // stop the main broadcast loop immediately (even if there are unbroadcast events left)
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