从RabbitMQ队列读取时如何检测错误

Question

I'm reading messages from RabbitMQ queue like this:

messages, err := channel.Consume(
    queue,  // queue
    queue,  // consumer - same as queue
    false,  // auto-ack
    false,  // exclusive
    false,  // no-local
    false,  // no-wait
    nil)    // args
if err != nil {
    // handle error
}

loop:   
for {
    select {
    case cmd := <-cmdChannel:
        if cmd == cmdStop {
            break loop
        }
    case message := <-messages:
        go process(message)
    }
}

There could be situations when reading from messages fail, like network error, or RabbitMQ's channel was invalidated due to an error. How to detect such errors and get relevant error message?

Answer 1

Assuming that you are using streadway/amqp, this is probably what you are looking for https://godoc.org/github.com/streadway/amqp#Channel.NotifyClose

func (*Channel) NotifyClose

func (ch *Channel) NotifyClose(c chan *Error) chan *Error

NotifyClose registers a listener for when the server sends a channel or connection exception in the form of a Connection.Close or Channel.Close method. Connection exceptions will be broadcast to all open channels and all channels will be closed, where channel exceptions will only be broadcast to listeners to this channel.

The chan provided will be closed when the Channel is closed and on a graceful close, no error will be sent.