TEST_F(RouterTest, RetryUpstreamConnectionFailure) {
  Http::ConnectionPool::Callbacks* conn_pool_callbacks;
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
      .WillOnce(Invoke([&](Http::StreamDecoder&, Http::ConnectionPool::Callbacks& callbacks)
                           -> Http::ConnectionPool::Cancellable* {
        conn_pool_callbacks = &callbacks;
        return nullptr;
      }));
  expectResponseTimerCreate();

  Http::TestRequestHeaderMapImpl headers{{"x-envoy-retry-on", "5xx"}, {"x-envoy-internal", "true"}};
  HttpTestUtility::addDefaultHeaders(headers);
  router_.decodeHeaders(headers, true);

  EXPECT_CALL(*router_.retry_state_, onHostAttempted(_)).Times(0);

  router_.retry_state_->expectResetRetry();

  conn_pool_callbacks->onPoolFailure(ConnectionPool::PoolFailureReason::RemoteConnectionFailure,
                                     absl::string_view(), nullptr);
  // Pool failure, so no upstream request was made.
  EXPECT_EQ(0U,
            callbacks_.route_->route_entry_.virtual_cluster_.stats().upstream_rq_total_.value());

  Http::ResponseDecoder* response_decoder = nullptr;
  // We expect this reset to kick off a new request.
  NiceMock<Http::MockRequestEncoder> encoder2;
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
      .WillOnce(Invoke(
          [&](Http::ResponseDecoder& decoder,
              Http::ConnectionPool::Callbacks& callbacks) -> Http::ConnectionPool::Cancellable* {
            response_decoder = &decoder;
            EXPECT_CALL(*router_.retry_state_, onHostAttempted(_));
            callbacks.onPoolReady(encoder2, cm_.thread_local_cluster_.conn_pool_.host_,
                                  upstream_stream_info_, Http::Protocol::Http10);
            return nullptr;
          }));
  router_.retry_state_->callback_();
  EXPECT_EQ(1U,
            callbacks_.route_->route_entry_.virtual_cluster_.stats().upstream_rq_total_.value());

  // Normal response.
  EXPECT_CALL(*router_.retry_state_, shouldRetryHeaders(_, _)).WillOnce(Return(RetryStatus::No));
  Http::ResponseHeaderMapPtr response_headers(
      new Http::TestResponseHeaderMapImpl{{":status", "200"}});
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_.host_->outlier_detector_,
              putHttpResponseCode(200));
  response_decoder->decodeHeaders(std::move(response_headers), true);
  EXPECT_TRUE(verifyHostUpstreamStats(1, 0));
}
TEST_F(RouterTest, RetryUpstreamConnectionFailure) {
  Http::ConnectionPool::Callbacks* conn_pool_callbacks;
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
      .WillOnce(Invoke([&](Http::StreamDecoder&, Http::ConnectionPool::Callbacks& callbacks)
                           -> Http::ConnectionPool::Cancellable* {
        conn_pool_callbacks = &callbacks;
        return nullptr;
      }));
  expectResponseTimerCreate();

  Http::TestRequestHeaderMapImpl headers{{"x-envoy-retry-on", "5xx"}, {"x-envoy-internal", "true"}};
  HttpTestUtility::addDefaultHeaders(headers);
  router_.decodeHeaders(headers, true);

  EXPECT_CALL(*router_.retry_state_, onHostAttempted(_)).Times(0);

  router_.retry_state_->expectResetRetry();

  conn_pool_callbacks->onPoolFailure(ConnectionPool::PoolFailureReason::RemoteConnectionFailure,
                                     absl::string_view(), nullptr);
   
  EXPECT_EQ(0U,
            callbacks_.route_->route_entry_.virtual_cluster_.stats().upstream_rq_total_.value());

  Http::ResponseDecoder* response_decoder = nullptr;
   
  NiceMock<Http::MockRequestEncoder> encoder2;
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_, newStream(_, _))
      .WillOnce(Invoke(
          [&](Http::ResponseDecoder& decoder,
              Http::ConnectionPool::Callbacks& callbacks) -> Http::ConnectionPool::Cancellable* {
            response_decoder = &decoder;
            EXPECT_CALL(*router_.retry_state_, onHostAttempted(_));
            callbacks.onPoolReady(encoder2, cm_.thread_local_cluster_.conn_pool_.host_,
                                  upstream_stream_info_, Http::Protocol::Http10);
            return nullptr;
          }));
  router_.retry_state_->callback_();
  EXPECT_EQ(1U,
            callbacks_.route_->route_entry_.virtual_cluster_.stats().upstream_rq_total_.value());

   
  EXPECT_CALL(*router_.retry_state_, shouldRetryHeaders(_, _)).WillOnce(Return(RetryStatus::No));
  Http::ResponseHeaderMapPtr response_headers(
      new Http::TestResponseHeaderMapImpl{{":status", "200"}});
  EXPECT_CALL(cm_.thread_local_cluster_.conn_pool_.host_->outlier_detector_,
              putHttpResponseCode(200));
  response_decoder->decodeHeaders(std::move(response_headers), true);
  EXPECT_TRUE(verifyHostUpstreamStats(1, 0));
}