main.go

package main

import (
        "log"
        "net/http"
        "io"
        "sync"
)

type Stream struct {
        reader io.ReadCloser
        done chan struct{}
}

func main() {

        log.Println("Starting up")

	channels := make(map[string]chan Stream)
	mutex := &sync.Mutex{}

	handler := func(w http.ResponseWriter, r *http.Request) {

                mutex.Lock()

                _, ok := channels[r.URL.Path]
                if !ok {
                        channels[r.URL.Path] = make(chan Stream)
                }

                channel := channels[r.URL.Path]

                mutex.Unlock()

                log.Println(channel)
                if r.Method == "GET" {

                        select {
                        case stream := <-channel:
                                io.Copy(w, stream.reader)
                                close(stream.done)
                        case <-r.Context().Done():
                                log.Println("consumer canceled")
                        }
                } else if r.Method == "POST" {

                        doneSignal := make(chan struct{})
                        stream := Stream{reader: r.Body, done: doneSignal}
                        select {
                        case channel <- stream:
                                log.Println("connected to consumer")
                        case <-r.Context().Done():
                                log.Println("producer canceled")
                        }

                        <-doneSignal
                }
        }

        err := http.ListenAndServe(":9001", http.HandlerFunc(handler))
        if err != nil {
                log.Fatal(err)
        }
}