New Streams and Quality structures

messaging/stream.go

@@ -0,0 +1,60 @@
+// Package messaging defines a structure to communication between inputs and outputs
+package messaging
+
+import (
+	"sync"
+)
+
+// Stream makes packages able to subscribe to an incoming stream
+type Stream struct {
+	// Different qualities of this stream
+	qualities map[string]*Quality
+
+	// Mutex to lock outputs map
+	lockQualities sync.Mutex
+
+	// Count clients for statistics
+	nbClients int
+}
+
+func newStream() (s *Stream) {
+	s = &Stream{}
+	s.qualities = make(map[string]*Quality)
+	s.nbClients = 0
+	return s
+}
+
+// CreateQuality creates a new quality associated with this stream.
+func (s *Stream) CreateQuality(name string) (quality *Quality) {
+	s.lockQualities.Lock()
+	quality = newQuality()
+	s.qualities[name] = quality
+	s.lockQualities.Unlock()
+	return quality
+}
+
+// DeleteQuality removes a quality.
+func (s *Stream) DeleteQuality(name string) {
+	// Make sure we did not already close this output
+	s.lockQualities.Lock()
+	if _, ok := s.qualities[name]; ok {
+		s.qualities[name].Close()
+		delete(s.qualities, name)
+	}
+	s.lockQualities.Unlock()
+}
+
+// ClientCount returns the number of clients.
+func (s *Stream) ClientCount() int {
+	return s.nbClients
+}
+
+// IncrementClientCount increments the number of clients.
+func (s *Stream) IncrementClientCount() {
+	s.nbClients++
+}
+
+// DecrementClientCount decrements the number of clients.
+func (s *Stream) DecrementClientCount() {
+	s.nbClients--
+}