Add FanOut proposal #166
Add FanOut proposal #166
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| @@ -34,6 +34,11 @@ type HandlerFunc func(msg *Message) ([]*Message, error) | |||
| // NoPublishHandlerFunc is HandlerFunc alternative, which doesn't produce any messages. | |||
| type NoPublishHandlerFunc func(msg *Message) error | |||
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| // PassthroughHandler is a handler that passes the message unchanged from the subscriber to the publisher. | |||
| var PassthroughHandler HandlerFunc = func(msg *Message) ([]*Message, error) { | |||
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You could use the alias Messages instead of []*Message, as we've done elsewhere.
If you think it'll improve readability
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HandlerFunc doesn't use it though, so maybe we should change them all at once?
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hmm I thought I saw some HandlerFuncs using Messages instead, maybe I was wrong
pubsub/gochannel/fanout.go
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| } | ||
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| // NewFanOut creates new FanOut. | ||
| // The passed router should not be running yet. |
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In principle, we could check if the router is already running (router.Running())?
Should we return error if this is the case?
Then cover it with the appropriate unit test ofc
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Oh right, that's a good idea. 👍
pubsub/gochannel/fanout.go
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| subscriber message.Subscriber, | ||
| logger watermill.LoggerAdapter, | ||
| ) (*FanOut, error) { | ||
| if router == nil { |
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basically, is there any case when we need to pass router?
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Moved to internal router in a96ad45
During development of ThreeDotsLabs/watermill-http#3 it occurred to me that we could abstract the "router" I created here, so this is a proposal of adding a
FanOutcomponent.This is essentially a wrapper over GoChannel Pub/Sub that lets you send messages coming from upstream subscriber to any number of internal publishers. This might be useful if you need a lot of subscribers and don't want to create a separate subscription for each of them.
Keep in mind this is an early idea, so feedback is welcome. Docs and more tests are obviously missing.
I also considered another API for this, that will create its own router and will be started just like a router. Maybe both could be available.