Goroutine无法运行

Question

I'm trying to use a goroutine to write item to database. The goroutine however doesn't seem to do anything for some reason.

I've got following functions:

func addEvent(w http.ResponseWriter, r *http.Request) {
    body, err := ioutil.ReadAll(r.Body)
    fmt.Println(string(body[:]))

    if err != nil {
        panic(err)
    }

    eventCh := make(chan []byte)
    eventCh <- body
    go models.WriteEventToDb(eventCh)

}

and

func WriteEventToDb(eventCh chan []byte) {
    fmt.Println("event")
    event := <-eventCh
    newEvent := createNewEvent(event)
    err := db.Insert(&newEvent)

    if err != nil {
        panic(err)
    }

}

Any idea why WriteEventToDb does not run?

Answer 1

Your function blocks before it gets to start the goroutine:

eventCh := make(chan []byte)
eventCh <- body

This makes a new channel, and before it can be passed off to any other routine, it tries to send a message to that channel. Since the channel is unbuffered and nothing is reading from it, the send blocks indefinitely.