[FIX] ignore Nats-Expected headers when process Inbound Source Msg

server/client.go

@@ -4131,6 +4131,34 @@ func removeHeaderIfPresent(hdr []byte, key string) []byte {
 	return hdr
 }
 
+func removeHeaderIfPrefixPresent(hdr []byte, prefix string) []byte {
+	var index int
+	for {
+		if index >= len(hdr) {
+			return hdr
+		}
+
+		start := bytes.Index(hdr[index:], []byte(prefix))
+		if start < 0 {
+			return hdr
+		}
+		index += start
+		if index < 1 || hdr[index-1] != '\n' {
+			return hdr
+		}
+
+		end := bytes.Index(hdr[index+len(prefix):], []byte(_CRLF_))
+		if end < 0 {
+			return hdr
+		}
+
+		hdr = append(hdr[:index], hdr[index+end+len(prefix)+len(_CRLF_):]...)
+		if len(hdr) <= len(emptyHdrLine) {
+			return nil
+		}
+	}
+}
+
 // Generate a new header based on optional original header and key value.
 // More used in JetStream layers.
 func genHeader(hdr []byte, key, value string) []byte {

server/client_test.go

@@ -2944,3 +2944,21 @@ func TestTLSClientHandshakeFirstAndInProcessConnection(t *testing.T) {
 		t.Fatal("Should have not got an error retrieving TLS connection state")
 	}
 }
+
+func TestRemoveHeaderIfPrefixPresent(t *testing.T) {
+	hdr := []byte("NATS/1.0\r\n\r\n")
+
+	hdr = genHeader(hdr, "a", "1")
+	hdr = genHeader(hdr, JSExpectedStream, "my-stream")
+	hdr = genHeader(hdr, JSExpectedLastSeq, "22")
+	hdr = genHeader(hdr, "b", "2")
+	hdr = genHeader(hdr, JSExpectedLastSubjSeq, "24")
+	hdr = genHeader(hdr, JSExpectedLastMsgId, "1")
+	hdr = genHeader(hdr, "c", "3")
+
+	hdr = removeHeaderIfPrefixPresent(hdr, "Nats-Expected-")
+
+	if !bytes.Equal(hdr, []byte("NATS/1.0\r\na: 1\r\nb: 2\r\nc: 3\r\n\r\n")) {
+		t.Fatalf("Expected headers to be stripped, got %q", hdr)
+	}
+}

server/jetstream_test.go

@@ -11968,6 +11968,60 @@ func TestJetStreamSourceWorkingQueueWithLimit(t *testing.T) {
 	}
 }
 
+func TestJetStreamStreamSourceFromKV(t *testing.T) {
+	s := RunBasicJetStreamServer(t)
+	defer s.Shutdown()
+
+	// Client for API reuqests.
+	nc, js := jsClientConnect(t, s)
+	defer nc.Close()
+
+	// Create a kv store
+	kv, err := js.CreateKeyValue(&nats.KeyValueConfig{Bucket: "test"})
+	require_NoError(t, err)
+
+	// Create a stream with a source from the kv store
+	_, err = js.AddStream(&nats.StreamConfig{Name: "test", Retention: nats.InterestPolicy, Sources: []*nats.StreamSource{{Name: "KV_" + kv.Bucket()}}})
+	require_NoError(t, err)
+
+	// Create a interested consumer
+	_, err = js.AddConsumer("test", &nats.ConsumerConfig{Durable: "durable", AckPolicy: nats.AckExplicitPolicy})
+	require_NoError(t, err)
+
+	ss, err := js.PullSubscribe("", "", nats.Bind("test", "durable"))
+	require_NoError(t, err)
+
+	rev1, err := kv.Create("key", []byte("value1"))
+	require_NoError(t, err)
+
+	m, err := ss.Fetch(1, nats.MaxWait(500*time.Millisecond))
+	require_NoError(t, err)
+	require_NoError(t, m[0].Ack())
+	if string(m[0].Data) != "value1" {
+		t.Fatalf("Expected value1, got %s", m[0].Data)
+	}
+
+	rev2, err := kv.Update("key", []byte("value2"), rev1)
+	require_NoError(t, err)
+
+	_, err = kv.Update("key", []byte("value3"), rev2)
+	require_NoError(t, err)
+
+	m, err = ss.Fetch(1, nats.MaxWait(500*time.Millisecond))
+	require_NoError(t, err)
+	require_NoError(t, m[0].Ack())
+	if string(m[0].Data) != "value2" {
+		t.Fatalf("Expected value2, got %s", m[0].Data)
+	}
+
+	m, err = ss.Fetch(1, nats.MaxWait(500*time.Millisecond))
+	require_NoError(t, err)
+	require_NoError(t, m[0].Ack())
+	if string(m[0].Data) != "value3" {
+		t.Fatalf("Expected value3, got %s", m[0].Data)
+	}
+}
+
 func TestJetStreamInputTransform(t *testing.T) {
 	s := RunBasicJetStreamServer(t)
 	defer s.Shutdown()

server/stream.go

@@ -3236,6 +3236,9 @@ func (mset *stream) processInboundSourceMsg(si *sourceInfo, m *inMsg) bool {
 	// If we are daisy chained here make sure to remove the original one.
 	if len(hdr) > 0 {
 		hdr = removeHeaderIfPresent(hdr, JSStreamSource)
+
+		// Remove any Nats-Expected- headers as we don't want to validate them.
+		hdr = removeHeaderIfPrefixPresent(hdr, "Nats-Expected-")
 	}
 	// Hold onto the origin reply which has all the metadata.
 	hdr = genHeader(hdr, JSStreamSource, si.genSourceHeader(m.rply))