consul: Adding support for sessions to FSM

consul/fsm.go

@@ -67,6 +67,8 @@ func (c *consulFSM) Apply(log *raft.Log) interface{} {
 		return c.applyDeregister(buf[1:], log.Index)
 	case structs.KVSRequestType:
 		return c.applyKVSOperation(buf[1:], log.Index)
+	case structs.SessionRequestType:
+		return c.applySessionOperation(buf[1:], log.Index)
 	default:
 		panic(fmt.Errorf("failed to apply request: %#v", buf))
 	}
@@ -152,6 +154,20 @@ func (c *consulFSM) applyKVSOperation(buf []byte, index uint64) interface{} {
 		} else {
 			return act
 		}
+	case structs.KVSLock:
+		act, err := c.state.KVSLock(index, &req.DirEnt)
+		if err != nil {
+			return err
+		} else {
+			return act
+		}
+	case structs.KVSUnlock:
+		act, err := c.state.KVSUnlock(index, &req.DirEnt)
+		if err != nil {
+			return err
+		} else {
+			return act
+		}
 	default:
 		c.logger.Printf("[WARN] consul.fsm: Invalid KVS operation '%s'", req.Op)
 		return fmt.Errorf("Invalid KVS operation '%s'", req.Op)
@@ -159,6 +175,23 @@ func (c *consulFSM) applyKVSOperation(buf []byte, index uint64) interface{} {
 	return nil
 }
 
+func (c *consulFSM) applySessionOperation(buf []byte, index uint64) interface{} {
+	var req structs.SessionRequest
+	if err := structs.Decode(buf, &req); err != nil {
+		panic(fmt.Errorf("failed to decode request: %v", err))
+	}
+	switch req.Op {
+	case structs.SessionCreate:
+		return c.state.SessionCreate(index, &req.Session)
+	case structs.SessionDestroy:
+		return c.state.SessionDestroy(index, req.Session.ID)
+	default:
+		c.logger.Printf("[WARN] consul.fsm: Invalid Session operation '%s'", req.Op)
+		return fmt.Errorf("Invalid Session operation '%s'", req.Op)
+	}
+	return nil
+}
+
 func (c *consulFSM) Snapshot() (raft.FSMSnapshot, error) {
 	defer func(start time.Time) {
 		c.logger.Printf("[INFO] consul.fsm: snapshot created in %v", time.Now().Sub(start))
@@ -222,6 +255,15 @@ func (c *consulFSM) Restore(old io.ReadCloser) error {
 				return err
 			}
 
+		case structs.SessionRequestType:
+			var req structs.Session
+			if err := dec.Decode(&req); err != nil {
+				return err
+			}
+			if err := c.state.SessionRestore(&req); err != nil {
+				return err
+			}
+
 		default:
 			return fmt.Errorf("Unrecognized msg type: %v", msgType)
 		}
@@ -244,6 +286,25 @@ func (s *consulSnapshot) Persist(sink raft.SnapshotSink) error {
 		return err
 	}
 
+	if err := s.persistNodes(sink, encoder); err != nil {
+		sink.Cancel()
+		return err
+	}
+
+	if err := s.persistSessions(sink, encoder); err != nil {
+		sink.Cancel()
+		return err
+	}
+
+	if err := s.persistKV(sink, encoder); err != nil {
+		sink.Cancel()
+		return err
+	}
+	return nil
+}
+
+func (s *consulSnapshot) persistNodes(sink raft.SnapshotSink,
+	encoder *codec.Encoder) error {
 	// Get all the nodes
 	nodes := s.state.Nodes()
 
@@ -258,7 +319,6 @@ func (s *consulSnapshot) Persist(sink raft.SnapshotSink) error {
 		// Register the node itself
 		sink.Write([]byte{byte(structs.RegisterRequestType)})
 		if err := encoder.Encode(&req); err != nil {
-			sink.Cancel()
 			return err
 		}
 
@@ -268,7 +328,6 @@ func (s *consulSnapshot) Persist(sink raft.SnapshotSink) error {
 			req.Service = srv
 			sink.Write([]byte{byte(structs.RegisterRequestType)})
 			if err := encoder.Encode(&req); err != nil {
-				sink.Cancel()
 				return err
 			}
 		}
@@ -280,16 +339,31 @@ func (s *consulSnapshot) Persist(sink raft.SnapshotSink) error {
 			req.Check = check
 			sink.Write([]byte{byte(structs.RegisterRequestType)})
 			if err := encoder.Encode(&req); err != nil {
-				sink.Cancel()
 				return err
 			}
 		}
 	}
+	return nil
+}
 
-	// Enable GC of the ndoes
-	nodes = nil
+func (s *consulSnapshot) persistSessions(sink raft.SnapshotSink,
+	encoder *codec.Encoder) error {
+	sessions, err := s.state.SessionList()
+	if err != nil {
+		return err
+	}
 
-	// Dump the KVS entries
+	for _, s := range sessions {
+		sink.Write([]byte{byte(structs.SessionRequestType)})
+		if err := encoder.Encode(s); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (s *consulSnapshot) persistKV(sink raft.SnapshotSink,
+	encoder *codec.Encoder) error {
 	streamCh := make(chan interface{}, 256)
 	errorCh := make(chan error)
 	go func() {
@@ -298,25 +372,21 @@ func (s *consulSnapshot) Persist(sink raft.SnapshotSink) error {
 		}
 	}()
 
-OUTER:
 	for {
 		select {
 		case raw := <-streamCh:
 			if raw == nil {
-				break OUTER
+				return nil
 			}
 			sink.Write([]byte{byte(structs.KVSRequestType)})
 			if err := encoder.Encode(raw); err != nil {
-				sink.Cancel()
 				return err
 			}
 
 		case err := <-errorCh:
-			sink.Cancel()
 			return err
 		}
 	}
-
 	return nil
 }
 

consul/structs/structs.go

@@ -19,6 +19,7 @@ const (
 	RegisterRequestType MessageType = iota
 	DeregisterRequestType
 	KVSRequestType
+	SessionRequestType
 )
 
 const (
@@ -348,6 +349,25 @@ type Session struct {
 	CreateIndex uint64
 }
 
+type SessionOp string
+
+const (
+	SessionCreate  SessionOp = "create"
+	SessionDestroy           = "destroy"
+)
+
+// SessionRequest is used to operate on sessions
+type SessionRequest struct {
+	Datacenter string
+	Op         SessionOp // Which operation are we performing
+	Session    Session   // Which session
+	WriteRequest
+}
+
+func (r *SessionRequest) RequestDatacenter() string {
+	return r.Datacenter
+}
+
 // Decode is used to decode a MsgPack encoded object
 func Decode(buf []byte, out interface{}) error {
 	var handle codec.MsgpackHandle