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) } // PullClose 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 }