Golang priority issues in select (Drip interview)

The first two days, in the Drip interview, was asked to achieve priority in select, but know that the event in select is triggered randomly, did not think how to implement, the interviewer told you can use the default implementation, think of the Golang document has said that his reading is not serious. Today it is found that the development of NSQ in use, hereby recorded.

for msg := range c.incomingMsgChan {    select {    case c.memoryMsgChan <- msg:    default:        err := WriteMessageToBackend(&msgBuf, msg, c.backend)        if err != nil {            // ... handle errors ...        }    }}Taking advantage of Go’s select statement allows this functionality to be expressed in just a few lines of code: the default case above only executes if memoryMsgChan is full.