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    No sleep until we build the ideal pub/sub library in Go go rauljordan.com
    andrewfromx avatar via andrewfromx 8 months ago |
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    | 4 comments
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      peterbourgon avatar peterbourgon edited 8 months ago

      I think I have a pretty good one.

      Basically,

      type Broker[T any] struct { ... }
func (b *Broker[T]) Subscribe(c chan<- T, allow func(T) bool) error
func (b *Broker[T]) Unsubscribe(c chan<- T) (Stats, error)
func (b *Broker[T]) Publish(v T) Stats
type Stats struct { Skips, Sends, Drops uint64 }

      That API is the result of many iterations over many years. Particularly critical is how subscribers are modeled as recv-only chans of type T, which callers are responsible for constructing and providing as input.

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        icholy avatar icholy 8 months ago

        Why the allow filter?

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          peterbourgon avatar peterbourgon edited 8 months ago

          Essentially just a first-pass filter to avoid sending unnecessary values. Definitely relies on some trust re: the caller.

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            oliverpool avatar oliverpool 8 months ago

            I think it allows for much nicer statistics and little bit faster processing (the allow function is called synchronously, which prevents the goroutine communication overhad - note that the caller can mess this up, if the allow function takes a while).