Allow for easy enterprise/oss coexistence

Uses struct/interface embedding with the embedded structs/interfaces being empty for oss. Also methods on the server/client types are defaulted to do nothing for OSS

agent/agent.go

@@ -73,6 +73,7 @@ type delegate interface {
 	SnapshotRPC(args *structs.SnapshotRequest, in io.Reader, out io.Writer, replyFn structs.SnapshotReplyFn) error
 	Shutdown() error
 	Stats() map[string]map[string]string
+	enterpriseDelegate
 }
 
 // notifier is called after a successful JoinLAN.

agent/consul/client.go

@@ -72,6 +72,9 @@ type Client struct {
 	shutdown     bool
 	shutdownCh   chan struct{}
 	shutdownLock sync.Mutex
+
+	// embedded struct to hold all the enterprise specific data
+	EnterpriseClient
 }
 
 // NewClient is used to construct a new Consul client from the
@@ -131,6 +134,11 @@ func NewClientLogger(config *Config, logger *log.Logger) (*Client, error) {
 		shutdownCh: make(chan struct{}),
 	}
 
+	if err := c.initEnterprise(); err != nil {
+		c.Shutdown()
+		return nil, err
+	}
+
 	// Initialize the LAN Serf
 	c.serf, err = c.setupSerf(config.SerfLANConfig,
 		c.eventCh, serfLANSnapshot)
@@ -147,6 +155,11 @@ func NewClientLogger(config *Config, logger *log.Logger) (*Client, error) {
 	// handlers depend on the router and the router depends on Serf.
 	go c.lanEventHandler()
 
+	if err := c.startEnterprise(); err != nil {
+		c.Shutdown()
+		return nil, err
+	}
+
 	return c, nil
 }
 
@@ -342,6 +355,17 @@ func (c *Client) Stats() map[string]map[string]string {
 		"serf_lan": c.serf.Stats(),
 		"runtime":  runtimeStats(),
 	}
+
+	for outerKey, outerValue := range c.enterpriseStats() {
+		if _, ok := stats[outerKey]; ok {
+			for innerKey, innerValue := range outerValue {
+				stats[outerKey][innerKey] = innerValue
+			}
+		} else {
+			stats[outerKey] = outerValue
+		}
+	}
+
 	return stats
 }
 

agent/consul/client_serf.go

@@ -135,6 +135,8 @@ func (c *Client) localEvent(event serf.UserEvent) {
 			c.config.UserEventHandler(event)
 		}
 	default:
+		if !c.handleEnterpriseUserEvents(event) {
 			c.logger.Printf("[WARN] consul: Unhandled local event: %v", event)
 		}
+	}
 }

agent/consul/enterprise_client_oss.go

@@ -0,0 +1,25 @@
+// +build !ent
+
+package consul
+
+import (
+	"github.com/hashicorp/serf/serf"
+)
+
+type EnterpriseClient struct{}
+
+func (c *Client) initEnterprise() error {
+	return nil
+}
+
+func (c *Client) startEnterprise() error {
+	return nil
+}
+
+func (c *Client) handleEnterpriseUserEvents(event serf.UserEvent) bool {
+	return false
+}
+
+func (c *Client) enterpriseStats() map[string]map[string]string {
+	return nil
+}

agent/consul/enterprise_server_oss.go

@@ -0,0 +1,32 @@
+// +build !ent
+
+package consul
+
+import (
+	"net"
+
+	"github.com/hashicorp/consul/agent/pool"
+	"github.com/hashicorp/serf/serf"
+)
+
+type EnterpriseServer struct{}
+
+func (s *Server) initEnterprise() error {
+	return nil
+}
+
+func (s *Server) startEnterprise() error {
+	return nil
+}
+
+func (s *Server) handleEnterpriseUserEvents(event serf.UserEvent) bool {
+	return false
+}
+
+func (s *Server) handleEnterpriseRPCConn(rtype pool.RPCType, conn net.Conn, isTLS bool) bool {
+	return false
+}
+
+func (s *Server) enterpriseStats() map[string]map[string]string {
+	return nil
+}

agent/consul/rpc.go

@@ -115,9 +115,10 @@ func (s *Server) handleConn(conn net.Conn, isTLS bool) {
 		s.handleSnapshotConn(conn)
 
 	default:
+		if !s.handleEnterpriseRPCConn(typ, conn, isTLS) {
 			s.logger.Printf("[ERR] consul.rpc: unrecognized RPC byte: %v %s", typ, logConn(conn))
 			conn.Close()
-		return
+		}
 	}
 }
 

agent/consul/server.go

@@ -208,6 +208,9 @@ type Server struct {
 	shutdown     bool
 	shutdownCh   chan struct{}
 	shutdownLock sync.Mutex
+
+	// embedded struct to hold all the enterprise specific data
+	EnterpriseServer
 }
 
 func NewServer(config *Config) (*Server, error) {
@@ -297,6 +300,12 @@ func NewServerLogger(config *Config, logger *log.Logger, tokens *token.Store) (*
 		shutdownCh:       shutdownCh,
 	}
 
+	// Initialize enterprise specific server functionality
+	if err := s.initEnterprise(); err != nil {
+		s.Shutdown()
+		return nil, err
+	}
+
 	// Initialize the stats fetcher that autopilot will use.
 	s.statsFetcher = NewStatsFetcher(logger, s.connPool, s.config.Datacenter)
 
@@ -338,6 +347,12 @@ func NewServerLogger(config *Config, logger *log.Logger, tokens *token.Store) (*
 		return nil, fmt.Errorf("Failed to start Raft: %v", err)
 	}
 
+	// Start enterprise specific functionality
+	if err := s.startEnterprise(); err != nil {
+		s.Shutdown()
+		return nil, err
+	}
+
 	// Serf and dynamic bind ports
 	//
 	// The LAN serf cluster announces the port of the WAN serf cluster
@@ -1019,6 +1034,17 @@ func (s *Server) Stats() map[string]map[string]string {
 	if s.serfWAN != nil {
 		stats["serf_wan"] = s.serfWAN.Stats()
 	}
+
+	for outerKey, outerValue := range s.enterpriseStats() {
+		if _, ok := stats[outerKey]; ok {
+			for innerKey, innerValue := range outerValue {
+				stats[outerKey][innerKey] = innerValue
+			}
+		} else {
+			stats[outerKey] = outerValue
+		}
+	}
+
 	return stats
 }
 

agent/consul/server_serf.go

@@ -198,8 +198,10 @@ func (s *Server) localEvent(event serf.UserEvent) {
 			s.config.UserEventHandler(event)
 		}
 	default:
+		if !s.handleEnterpriseUserEvents(event) {
 			s.logger.Printf("[WARN] consul: Unhandled local event: %v", event)
 		}
+	}
 }
 
 // lanNodeJoin is used to handle join events on the LAN pool.

agent/enterprise_delegate_oss.go

@@ -0,0 +1,6 @@
+// +build !ent
+
+package agent
+
+// enterpriseDelegate has no functions in OSS
+type enterpriseDelegate interface{}