4 files changed, 47 insertions, 5 deletions

diff --git a/include/grpcpp/impl/codegen/call_op_set.h b/include/grpcpp/impl/codegen/call_op_set.h
index 1f2b88e9e1..f330679ffc 100644
--- a/include/grpcpp/impl/codegen/call_op_set.h
+++ b/include/grpcpp/impl/codegen/call_op_set.h
@@ -315,9 +315,16 @@ class CallOpSendMessage {
     write_options_.Clear();
   }
   void FinishOp(bool* status) {
-    send_buf_.Clear();
+    if (!send_buf_.Valid()) {
+      return;
+    }
     if (hijacked_ && failed_send_) {
+      // Hijacking interceptor failed this Op
       *status = false;
+    } else if (!*status) {
+      // This Op was passed down to core and the Op failed
+      gpr_log(GPR_ERROR, "failure status");
+      failed_send_ = true;
     }
   }
 
@@ -330,7 +337,14 @@ class CallOpSendMessage {
   }
 
   void SetFinishInterceptionHookPoint(
-      InterceptorBatchMethodsImpl* interceptor_methods) {}
+      InterceptorBatchMethodsImpl* interceptor_methods) {
+    if (send_buf_.Valid()) {
+      interceptor_methods->AddInterceptionHookPoint(
+          experimental::InterceptionHookPoints::POST_SEND_MESSAGE);
+      // We had already registered failed_send_ earlier. No need to do it again.
+    }
+    send_buf_.Clear();
+  }
 
   void SetHijackingState(InterceptorBatchMethodsImpl* interceptor_methods) {
     hijacked_ = true;
diff --git a/include/grpcpp/impl/codegen/interceptor.h b/include/grpcpp/impl/codegen/interceptor.h
index 47239332c8..154172dd81 100644
--- a/include/grpcpp/impl/codegen/interceptor.h
+++ b/include/grpcpp/impl/codegen/interceptor.h
@@ -41,9 +41,10 @@ class InterceptedMessage {
 };
 
 enum class InterceptionHookPoints {
-  /* The first two in this list are for clients and servers */
+  /* The first three in this list are for clients and servers */
   PRE_SEND_INITIAL_METADATA,
   PRE_SEND_MESSAGE,
+  POST_SEND_MESSAGE,
   PRE_SEND_STATUS /* server only */,
   PRE_SEND_CLOSE /* client only */,
   /* The following three are for hijacked clients only and can only be
@@ -85,6 +86,9 @@ class InterceptorBatchMethods {
   // sent
   virtual ByteBuffer* GetSendMessage() = 0;
 
+  // Checks whether the SEND MESSAGE op succeeded
+  virtual bool GetSendMessageStatus() = 0;
+
   // Returns a modifiable multimap of the initial metadata to be sent
   virtual std::multimap<grpc::string, grpc::string>*
   GetSendInitialMetadata() = 0;
diff --git a/include/grpcpp/impl/codegen/interceptor_common.h b/include/grpcpp/impl/codegen/interceptor_common.h
index 601a929afe..21326df73b 100644
--- a/include/grpcpp/impl/codegen/interceptor_common.h
+++ b/include/grpcpp/impl/codegen/interceptor_common.h
@@ -81,6 +81,8 @@ class InterceptorBatchMethodsImpl
 
   ByteBuffer* GetSendMessage() override { return send_message_; }
 
+  bool GetSendMessageStatus() override { return !*fail_send_message_; }
+
   std::multimap<grpc::string, grpc::string>* GetSendInitialMetadata() override {
     return send_initial_metadata_;
   }
@@ -113,6 +115,7 @@ class InterceptorBatchMethodsImpl
   void FailHijackedSendMessage() override {
     GPR_CODEGEN_ASSERT(hooks_[static_cast<size_t>(
         experimental::InterceptionHookPoints::PRE_SEND_MESSAGE)]);
+    gpr_log(GPR_ERROR, "failing");
     *fail_send_message_ = true;
   }
 
@@ -396,6 +399,13 @@ class CancelInterceptorBatchMethods
     return nullptr;
   }
 
+  bool GetSendMessageStatus() override {
+    GPR_CODEGEN_ASSERT(
+        false &&
+        "It is illegal to call GetSendMessageStatus on a method which "
+        "has a Cancel notification");
+  }
+
   std::multimap<grpc::string, grpc::string>* GetSendInitialMetadata() override {
     GPR_CODEGEN_ASSERT(false &&
                        "It is illegal to call GetSendInitialMetadata on a "
diff --git a/test/cpp/end2end/client_interceptors_end2end_test.cc b/test/cpp/end2end/client_interceptors_end2end_test.cc
index 81efd15452..97947e7393 100644
--- a/test/cpp/end2end/client_interceptors_end2end_test.cc
+++ b/test/cpp/end2end/client_interceptors_end2end_test.cc
@@ -288,6 +288,13 @@ class ClientStreamingRpcHijackingInterceptor
       }
     }
     if (methods->QueryInterceptionHookPoint(
+            experimental::InterceptionHookPoints::POST_SEND_MESSAGE)) {
+      EXPECT_FALSE(got_failed_send_);
+      gpr_log(GPR_ERROR, "%d", got_failed_send_);
+      got_failed_send_ = !methods->GetSendMessageStatus();
+      gpr_log(GPR_ERROR, "%d", got_failed_send_);
+    }
+    if (methods->QueryInterceptionHookPoint(
             experimental::InterceptionHookPoints::PRE_RECV_STATUS)) {
       auto* status = methods->GetRecvStatus();
       *status = Status(StatusCode::UNAVAILABLE, "Done sending 10 messages");
@@ -299,10 +306,16 @@ class ClientStreamingRpcHijackingInterceptor
     }
   }
 
+  static bool GotFailedSend() { return got_failed_send_; }
+
  private:
   experimental::ClientRpcInfo* info_;
   int count_ = 0;
+  static bool got_failed_send_;
 };
+
+bool ClientStreamingRpcHijackingInterceptor::got_failed_send_ = false;
+
 class ClientStreamingRpcHijackingInterceptorFactory
     : public experimental::ClientInterceptorFactoryInterface {
  public:
@@ -602,10 +615,11 @@ TEST_F(ClientInterceptorsStreamingEnd2endTest, ClientStreamingHijackingTest) {
     EXPECT_TRUE(writer->Write(req));
     expected_resp += "Hello";
   }
-  // Expect that the interceptor will reject the 11th message
-  EXPECT_FALSE(writer->Write(req));
+  // The interceptor will reject the 11th message
+  writer->Write(req);
   Status s = writer->Finish();
   EXPECT_EQ(s.ok(), false);
+  EXPECT_TRUE(ClientStreamingRpcHijackingInterceptor::GotFailedSend());
 }
 
 TEST_F(ClientInterceptorsStreamingEnd2endTest, BidiStreamingTest) {