func (dispatcher *dispatcher) Dispatch(in stream.Readable, writables ...stream.Writable) stream.Readable {
notDispatchedReadable, notDispatchedWritable := stream.New(in.Capacity())
dispatchedCount := 0
done := make(chan bool, len(writables))
closeWritables := func() {
defer func() {
for _, writable := range writables {
close(writable)
}
}()
expectedDoneMessages := dispatchedCount * len(writables)
for i := 0; i < expectedDoneMessages; i++ {
select {
case <-dispatcher.context.Failure():
return
case <-time.After(dispatcher.context.Deadline()):
panic(stream.Timeout)
case <-done:
continue
}
}
}
go func() {
defer dispatcher.context.Recover()
defer close(notDispatchedWritable)
defer closeWritables()
for data := range in {
select {
case <-dispatcher.context.Failure():
return
case <-time.After(dispatcher.context.Deadline()):
panic(stream.Timeout)
default:
if dispatcher.fn(data) {
dispatchedCount++
for _, writable := range writables {
// dispatch data asynchronously so that
// slow receivers don't block the dispatch
// process
go func(w stream.Writable, d stream.T) {
w <- d
done <- true
}(writable, data)
}
} else {
notDispatchedWritable <- data
}
}
}
}()
return notDispatchedReadable
}
func (observer *Observer) Transform(in stream.Readable) stream.Readable {
readable, writable := stream.New(in.Capacity())
emitter := stream.NewEmitter(observer.context, writable)
go func() {
defer observer.context.Recover()
defer close(writable)
for {
select {
case <-observer.context.Failure():
return
case <-observer.context.Done():
return
case <-time.After(observer.context.Deadline()):
panic(stream.Timeout)
default:
data, more := <-in
if !more {
if observer.OnCompleted != nil {
observer.OnCompleted(emitter)
}
return
}
if observer.OnNext == nil {
continue
}
if err := observer.OnNext(data, emitter); err != nil {
if err == stream.Done {
// Tell producer to shutdown without errors
observer.context.Close(nil)
return
}
panic(err)
}
}
}
}()
return readable
}
