[FAB-10284] Fix tx-id race with sending response

Change-Id: I6863621e0f6c9eda47e6d37027f059a4ec3028b6
Signed-off-by: Matthew Sykes <sykesmat@us.ibm.com>

Author: sykesm

core/chaincode/handler.go

@@ -249,8 +249,8 @@ func (h *Handler) HandleTransaction(msg *pb.ChaincodeMessage, delegate handleFun
 	}
 
 	chaincodeLogger.Debugf("[%s] Completed %s. Sending %s", shorttxid(msg.Txid), msg.Type, resp.Type)
-	h.serialSendAsync(resp, false)
 	h.ActiveTransactions.Remove(msg.ChannelId, msg.Txid)
+	h.serialSendAsync(resp, false)
 }
 
 func shorttxid(txid string) string {

core/chaincode/handler_test.go

@@ -157,7 +157,11 @@ var _ = Describe("Handler", func() {
 			Expect(msg).To(Equal(expectedResponse))
 		})
 
-		It("deregisters the message transaction ID", func() {
+		It("deregisters the transaction ID before sending the response", func() {
+			fakeTransactionRegistry.RemoveStub = func(channelID, txID string) {
+				Consistently(fakeChatStream.SendCallCount).Should(Equal(0))
+			}
+
 			handler.HandleTransaction(incomingMessage, fakeMessageHandler.Handle)
 
 			Expect(fakeTransactionRegistry.RemoveCallCount()).To(Equal(1))