Command#Apply is passed inconsistent context information.

server.go

@@ -199,7 +199,7 @@ func NewServer(name string, path string, transporter Transporter, stateMachine S
 			return c.Apply(&context{
 				server:       s,
 				currentTerm:  s.currentTerm,
-				currentIndex: s.log.internalCurrentIndex(),
+				currentIndex: e.Index(),
 				commitIndex:  s.log.commitIndex,
 			})
 		case deprecatedCommandApply:

server_test.go

@@ -271,6 +271,45 @@ func TestServerAppendEntries(t *testing.T) {
 	}
 }
 
+// Ensure we can append entries to a server.
+func TestServerProvidesCurrentContextWhenApplyingCommand(t *testing.T) {
+	s := newTestServer("1", &testTransporter{})
+
+	s.SetHeartbeatInterval(time.Second * 10)
+	s.Start()
+	defer s.Stop()
+
+	// Append single entry.
+	appliedContexts = make([]Context, 0)
+
+	e, _ := newLogEntry(nil, nil, 1, 1, &testApplyCommand{Val: "foo", I: 10})
+	entries := []*LogEntry{e}
+	s.AppendEntries(newAppendEntriesRequest(1, 0, 0, 1, "ldr", entries))
+	if len(appliedContexts) != 1 {
+		t.Fatalf("Called Apply %v times (expected 1)", len(appliedContexts))
+	}
+	if appliedContexts[0].CommitIndex() != 1 || appliedContexts[0].CurrentIndex() != 1 {
+		t.Fatalf("Invalid context index info [Current=%v, Commit=%v]", appliedContexts[0].CurrentIndex(), appliedContexts[0].CommitIndex())
+	}
+
+	// Append multiple entries + commit the last one.
+	appliedContexts = make([]Context, 0)
+
+	e1, _ := newLogEntry(nil, nil, 2, 1, &testApplyCommand{Val: "bar", I: 20})
+	e2, _ := newLogEntry(nil, nil, 3, 1, &testApplyCommand{Val: "baz", I: 30})
+	entries = []*LogEntry{e1, e2}
+	s.AppendEntries(newAppendEntriesRequest(1, 1, 1, 3, "ldr", entries))
+	if len(appliedContexts) != 2 {
+		t.Fatalf("Called Apply %v times (expected 2)", len(appliedContexts))
+	}
+	if appliedContexts[0].CommitIndex() != 2 || appliedContexts[0].CurrentIndex() != 2 {
+		t.Fatalf("Invalid context index info [Current=%v, Commit=%v]", appliedContexts[0].CurrentIndex(), appliedContexts[0].CommitIndex())
+	}
+	if appliedContexts[1].CommitIndex() != 3 || appliedContexts[1].CurrentIndex() != 3 {
+		t.Fatalf("Invalid context index info [Current=%v, Commit=%v]", appliedContexts[1].CurrentIndex(), appliedContexts[1].CommitIndex())
+	}
+}
+
 //Ensure that entries with stale terms are rejected.
 func TestServerAppendEntriesWithStaleTermsAreRejected(t *testing.T) {
 	s := newTestServer("1", &testTransporter{})

test.go

@@ -19,6 +19,7 @@ const (
 func init() {
 	RegisterCommand(&testCommand1{})
 	RegisterCommand(&testCommand2{})
+	RegisterCommand(&testApplyCommand{})
 }
 
 //------------------------------------------------------------------------------
@@ -195,3 +196,28 @@ func (c *testCommand2) CommandName() string {
 func (c *testCommand2) Apply(server Server) (interface{}, error) {
 	return nil, nil
 }
+
+//-----------------------------------------------
+// ApplyCommand - testing passed content to Apply
+//-----------------------------------------------
+
+var appliedContexts []Context
+
+type testApplyCommand struct {
+	Val string `json:"val"`
+	I   int    `json:"i"`
+}
+
+func (c *testApplyCommand) CommandName() string {
+	return "cmd_apply"
+}
+
+func (c *testApplyCommand) Apply(context Context) (interface{}, error) {
+	if appliedContexts == nil {
+		appliedContexts = make([]Context, 0)
+	}
+
+	appliedContexts = append(appliedContexts, context)
+
+	return nil, nil
+}