Encode config entry FSM messages in a generic type

agent/consul/fsm/commands_oss.go

@@ -29,8 +29,7 @@ func init() {
 	registerCommand(structs.ACLPolicySetRequestType, (*FSM).applyACLPolicySetOperation)
 	registerCommand(structs.ACLPolicyDeleteRequestType, (*FSM).applyACLPolicyDeleteOperation)
 	registerCommand(structs.ConnectCALeafRequestType, (*FSM).applyConnectCALeafOperation)
-	registerCommand(structs.ServiceConfigEntryRequestType, (*FSM).applyServiceConfigEntryOperation)
-	registerCommand(structs.ProxyConfigEntryRequestType, (*FSM).applyProxyConfigEntryOperation)
+	registerCommand(structs.ConfigEntryRequestType, (*FSM).applyConfigEntryOperation)
 }
 
 func (c *FSM) applyRegister(buf []byte, index uint64) interface{} {
@@ -431,30 +430,14 @@ func (c *FSM) applyACLPolicyDeleteOperation(buf []byte, index uint64) interface{
 	return c.state.ACLPolicyBatchDelete(index, req.PolicyIDs)
 }
 
-func (c *FSM) applyServiceConfigEntryOperation(buf []byte, index uint64) interface{} {
-	req := structs.ConfigEntryRequest{
-		Entry: &structs.ServiceConfigEntry{},
-	}
-	if err := structs.Decode(buf, &req); err != nil {
-		panic(fmt.Errorf("failed to decode request: %v", err))
-	}
-	return c.applyConfigEntryOperation(index, req)
-}
-
-func (c *FSM) applyProxyConfigEntryOperation(buf []byte, index uint64) interface{} {
+func (c *FSM) applyConfigEntryOperation(buf []byte, index uint64) interface{} {
 	req := structs.ConfigEntryRequest{
 		Entry: &structs.ProxyConfigEntry{},
 	}
 	if err := structs.Decode(buf, &req); err != nil {
 		panic(fmt.Errorf("failed to decode request: %v", err))
 	}
-	if err := c.applyConfigEntryOperation(index, req); err != nil {
-		panic(err)
-	}
-	return true
-}
 
-func (c *FSM) applyConfigEntryOperation(index uint64, req structs.ConfigEntryRequest) error {
 	switch req.Op {
 	case structs.ConfigEntryUpsert:
 		defer metrics.MeasureSinceWithLabels([]string{"fsm", "config_entry", req.Entry.GetKind()}, time.Now(),

agent/consul/fsm/commands_oss_test.go

@@ -1368,21 +1368,24 @@ func TestFSM_ConfigEntry(t *testing.T) {
 	entry := &structs.ProxyConfigEntry{
 		Kind: structs.ProxyDefaults,
 		Name: "global",
-		ProxyConfig: structs.ConnectProxyConfig{
-			DestinationServiceName: "foo",
+		Config: map[string]interface{}{
+			"DestinationServiceName": "foo",
 		},
 	}
 
 	// Create a new request.
-	req := structs.ConfigEntryRequest{
+	req := &structs.ConfigEntryRequest{
 		Op:    structs.ConfigEntryUpsert,
 		Entry: entry,
 	}
 
 	{
-		buf, err := structs.Encode(structs.ProxyConfigEntryRequestType, req)
+		buf, err := structs.Encode(structs.ConfigEntryRequestType, req)
 		require.NoError(err)
-		require.True(fsm.Apply(makeLog(buf)).(bool))
+		resp := fsm.Apply(makeLog(buf))
+		if _, ok := resp.(error); ok {
+			t.Fatalf("bad: %v", resp)
+		}
 	}
 
 	// Verify it's in the state store.
@@ -1391,6 +1394,14 @@ func TestFSM_ConfigEntry(t *testing.T) {
 		require.NoError(err)
 		entry.RaftIndex.CreateIndex = 1
 		entry.RaftIndex.ModifyIndex = 1
+
+		proxyConf, ok := config.(*structs.ProxyConfigEntry)
+		require.True(ok)
+
+		// Read the map[string]interface{} back out.
+		value, _ := proxyConf.Config["DestinationServiceName"].([]uint8)
+		proxyConf.Config["DestinationServiceName"] = structs.Uint8ToString(value)
+
 		require.Equal(entry, config)
 	}
 }

agent/consul/fsm/snapshot_oss.go

@@ -1,8 +1,6 @@
 package fsm
 
 import (
-	"fmt"
-
 	"github.com/hashicorp/consul/agent/consul/autopilot"
 	"github.com/hashicorp/consul/agent/consul/state"
 	"github.com/hashicorp/consul/agent/structs"
@@ -377,10 +375,10 @@ func (s *snapshot) persistConfigEntries(sink raft.SnapshotSink,
 		if _, err := sink.Write([]byte{byte(structs.ConfigEntryRequestType)}); err != nil {
 			return err
 		}
-		if err := encoder.Encode(entry.GetKind()); err != nil {
-			return err
+		req := &structs.ConfigEntryRequest{
+			Entry: entry,
 		}
-		if err := encoder.Encode(entry); err != nil {
+		if err := encoder.Encode(req); err != nil {
 			return err
 		}
 	}
@@ -594,23 +592,9 @@ func restorePolicy(header *snapshotHeader, restore *state.Restore, decoder *code
 }
 
 func restoreConfigEntry(header *snapshotHeader, restore *state.Restore, decoder *codec.Decoder) error {
-	var req structs.ConfigEntry
-	var kind string
-	if err := decoder.Decode(&kind); err != nil {
-		return err
-	}
-
-	switch kind {
-	case structs.ServiceDefaults:
-		req = &structs.ServiceConfigEntry{}
-	case structs.ProxyDefaults:
-		req = &structs.ProxyConfigEntry{}
-	default:
-		return fmt.Errorf("invalid config type: %s", kind)
-	}
-
+	var req structs.ConfigEntryRequest
 	if err := decoder.Decode(&req); err != nil {
 		return err
 	}
-	return restore.ConfigEntry(req)
+	return restore.ConfigEntry(req.Entry)
 }

agent/consul/fsm/snapshot_oss_test.go

@@ -317,8 +317,8 @@ func TestFSM_SnapshotRestore_OSS(t *testing.T) {
 	// Verify ACL Token is restored
 	_, a, err := fsm2.state.ACLTokenGetByAccessor(nil, token.AccessorID)
 	require.NoError(err)
-	require.Equal(t, token.AccessorID, a.AccessorID)
-	require.Equal(t, token.ModifyIndex, a.ModifyIndex)
+	require.Equal(token.AccessorID, a.AccessorID)
+	require.Equal(token.ModifyIndex, a.ModifyIndex)
 
 	// Verify the acl-token-bootstrap index was restored
 	canBootstrap, index, err := fsm2.state.CanBootstrapACLToken()

agent/structs/config_entry.go

@@ -3,6 +3,8 @@ package structs
 import (
 	"fmt"
 	"strings"
+
+	"github.com/hashicorp/go-msgpack/codec"
 )
 
 const (
@@ -163,3 +165,62 @@ type ConfigEntryRequest struct {
 	Op    ConfigEntryOp
 	Entry ConfigEntry
 }
+
+func (r *ConfigEntryRequest) MarshalBinary() (data []byte, err error) {
+	// bs will grow if needed but allocate enough to avoid reallocation in common
+	// case.
+	bs := make([]byte, 128)
+	enc := codec.NewEncoderBytes(&bs, msgpackHandle)
+	// Encode kind first
+	err = enc.Encode(r.Entry.GetKind())
+	if err != nil {
+		return nil, err
+	}
+	// Then actual value using alias trick to avoid infinite recursion
+	type Alias ConfigEntryRequest
+	err = enc.Encode(struct {
+		*Alias
+	}{
+		Alias: (*Alias)(r),
+	})
+	if err != nil {
+		return nil, err
+	}
+	return bs, nil
+}
+
+func (r *ConfigEntryRequest) UnmarshalBinary(data []byte) error {
+	// First decode the kind prefix
+	var kind string
+	dec := codec.NewDecoderBytes(data, msgpackHandle)
+	if err := dec.Decode(&kind); err != nil {
+		return err
+	}
+
+	// Then decode the real thing with appropriate kind of ConfigEntry
+	r.Entry = makeConfigEntry(kind)
+
+	// Alias juggling to prevent infinite recursive calls back to this decode
+	// method.
+	type Alias ConfigEntryRequest
+	as := struct {
+		*Alias
+	}{
+		Alias: (*Alias)(r),
+	}
+	if err := dec.Decode(&as); err != nil {
+		return err
+	}
+	return nil
+}
+
+func makeConfigEntry(kind string) ConfigEntry {
+	switch kind {
+	case ServiceDefaults:
+		return &ServiceConfigEntry{}
+	case ProxyDefaults:
+		return &ProxyConfigEntry{}
+	default:
+		panic("invalid kind")
+	}
+}

agent/structs/structs.go

@@ -33,31 +33,29 @@ type RaftIndex struct {
 // These are serialized between Consul servers and stored in Consul snapshots,
 // so entries must only ever be added.
 const (
-	RegisterRequestType           MessageType = 0
-	DeregisterRequestType                     = 1
-	KVSRequestType                            = 2
-	SessionRequestType                        = 3
-	ACLRequestType                            = 4 // DEPRECATED (ACL-Legacy-Compat)
-	TombstoneRequestType                      = 5
-	CoordinateBatchUpdateType                 = 6
-	PreparedQueryRequestType                  = 7
-	TxnRequestType                            = 8
-	AutopilotRequestType                      = 9
-	AreaRequestType                           = 10
-	ACLBootstrapRequestType                   = 11
-	IntentionRequestType                      = 12
-	ConnectCARequestType                      = 13
-	ConnectCAProviderStateType                = 14
-	ConnectCAConfigType                       = 15 // FSM snapshots only.
-	IndexRequestType                          = 16 // FSM snapshots only.
-	ACLTokenSetRequestType                    = 17
-	ACLTokenDeleteRequestType                 = 18
-	ACLPolicySetRequestType                   = 19
-	ACLPolicyDeleteRequestType                = 20
-	ConnectCALeafRequestType                  = 21
-	ConfigEntryRequestType                    = 22 // FSM snapshots only.
-	ServiceConfigEntryRequestType             = 23
-	ProxyConfigEntryRequestType               = 24
+	RegisterRequestType        MessageType = 0
+	DeregisterRequestType                  = 1
+	KVSRequestType                         = 2
+	SessionRequestType                     = 3
+	ACLRequestType                         = 4 // DEPRECATED (ACL-Legacy-Compat)
+	TombstoneRequestType                   = 5
+	CoordinateBatchUpdateType              = 6
+	PreparedQueryRequestType               = 7
+	TxnRequestType                         = 8
+	AutopilotRequestType                   = 9
+	AreaRequestType                        = 10
+	ACLBootstrapRequestType                = 11
+	IntentionRequestType                   = 12
+	ConnectCARequestType                   = 13
+	ConnectCAProviderStateType             = 14
+	ConnectCAConfigType                    = 15 // FSM snapshots only.
+	IndexRequestType                       = 16 // FSM snapshots only.
+	ACLTokenSetRequestType                 = 17
+	ACLTokenDeleteRequestType              = 18
+	ACLPolicySetRequestType                = 19
+	ACLPolicyDeleteRequestType             = 20
+	ConnectCALeafRequestType               = 21
+	ConfigEntryRequestType                 = 22 // FSM snapshots only.
 )
 
 const (