woodpecker/queue/queue.go
2016-05-11 18:53:48 +08:00

67 lines
2 KiB
Go

package queue
//go:generate mockery -name Queue -output mock -case=underscore
import (
"errors"
"golang.org/x/net/context"
)
// ErrNotFound indicates the requested work item does not
// exist in the queue.
var ErrNotFound = errors.New("queue item not found")
type Queue interface {
// Publish inserts work at the tail of this queue, waiting for
// space to become available if the queue is full.
Publish(*Work) error
// Remove removes the specified work item from this queue,
// if it is present.
Remove(*Work) error
// PullClose retrieves and removes the head of this queue,
// waiting if necessary until work becomes available.
Pull() *Work
// PullClose retrieves and removes the head of this queue,
// waiting if necessary until work becomes available. The
// CloseNotifier should be provided to clone the channel
// if the subscribing client terminates its connection.
PullClose(CloseNotifier) *Work
}
// Publish inserts work at the tail of this queue, waiting for
// space to become available if the queue is full.
func Publish(c context.Context, w *Work) error {
return FromContext(c).Publish(w)
}
// Remove removes the specified work item from this queue,
// if it is present.
func Remove(c context.Context, w *Work) error {
return FromContext(c).Remove(w)
}
// Pull retrieves and removes the head of this queue,
// waiting if necessary until work becomes available.
func Pull(c context.Context) *Work {
return FromContext(c).Pull()
}
// PullClose retrieves and removes the head of this queue,
// waiting if necessary until work becomes available. The
// CloseNotifier should be provided to clone the channel
// if the subscribing client terminates its connection.
func PullClose(c context.Context, cn CloseNotifier) *Work {
return FromContext(c).PullClose(cn)
}
// CloseNotifier defines a datastructure that is capable of notifying
// a subscriber when its connection is closed.
type CloseNotifier interface {
// CloseNotify returns a channel that receives a single value
// when the client connection has gone away.
CloseNotify() <-chan bool
}