// ListenSubscriptions returns a stream of matching subscriptions for the current node
func (lb *LogBroker) ListenSubscriptions(request *api.ListenSubscriptionsRequest, stream api.LogBroker_ListenSubscriptionsServer) error {
remote, err := ca.RemoteNode(stream.Context())
if err != nil {
return err
}
log := log.G(stream.Context()).WithFields(
logrus.Fields{
"method": "(*LogBroker).ListenSubscriptions",
"node": remote.NodeID,
},
)
subscriptions, subscriptionCh, subscriptionCancel := lb.watchSubscriptions()
defer subscriptionCancel()
log.Debug("node registered")
// Start by sending down all active subscriptions.
for _, subscription := range subscriptions {
select {
case <-stream.Context().Done():
return stream.Context().Err()
case <-lb.pctx.Done():
return nil
default:
}
if err := stream.Send(subscription); err != nil {
log.Error(err)
return err
}
}
// Send down new subscriptions.
// TODO(aluzzardi): We should filter by relevant tasks for this node rather
for {
select {
case v := <-subscriptionCh:
subscription := v.(*api.SubscriptionMessage)
if err := stream.Send(subscription); err != nil {
log.Error(err)
return err
}
case <-stream.Context().Done():
return stream.Context().Err()
case <-lb.pctx.Done():
return nil
}
}
}
// ListenSubscriptions returns a stream of matching subscriptions for the current node
func (lb *LogBroker) ListenSubscriptions(request *api.ListenSubscriptionsRequest, stream api.LogBroker_ListenSubscriptionsServer) error {
remote, err := ca.RemoteNode(stream.Context())
if err != nil {
return err
}
lb.nodeConnected(remote.NodeID)
defer lb.nodeDisconnected(remote.NodeID)
log := log.G(stream.Context()).WithFields(
logrus.Fields{
"method": "(*LogBroker).ListenSubscriptions",
"node": remote.NodeID,
},
)
subscriptions, subscriptionCh, subscriptionCancel := lb.watchSubscriptions(remote.NodeID)
defer subscriptionCancel()
log.Debug("node registered")
activeSubscriptions := make(map[string]*subscription)
defer func() {
// If the worker quits, mark all active subscriptions as finished.
for _, subscription := range activeSubscriptions {
subscription.Done(remote.NodeID, fmt.Errorf("node %s disconnected unexpectedly", remote.NodeID))
}
}()
// Start by sending down all active subscriptions.
for _, subscription := range subscriptions {
select {
case <-stream.Context().Done():
return stream.Context().Err()
case <-lb.pctx.Done():
return nil
default:
}
if err := stream.Send(subscription.message); err != nil {
log.Error(err)
return err
}
activeSubscriptions[subscription.message.ID] = subscription
}
// Send down new subscriptions.
for {
select {
case v := <-subscriptionCh:
subscription := v.(*subscription)
if subscription.message.Close {
log.WithField("subscription.id", subscription.message.ID).Debug("subscription closed")
delete(activeSubscriptions, subscription.message.ID)
} else {
// Avoid sending down the same subscription multiple times
if _, ok := activeSubscriptions[subscription.message.ID]; ok {
continue
}
activeSubscriptions[subscription.message.ID] = subscription
log.WithField("subscription.id", subscription.message.ID).Debug("subscription added")
}
if err := stream.Send(subscription.message); err != nil {
log.Error(err)
return err
}
case <-stream.Context().Done():
return stream.Context().Err()
case <-lb.pctx.Done():
return nil
}
}
}