Add stats for timeouts (#10)

Author: ccaraman

source/common/http/async_client_impl.cc

@@ -126,6 +126,7 @@ void AsyncRequestImpl::onRequestTimeout() {
                                            REQUEST_TIMEOUT_HEADER, true, EMPTY_STRING,
                                            EMPTY_STRING};
   Http::CodeUtility::chargeResponseStat(info);
+  parent_.stats_store_.counter(fmt::format("{}upstream_rq_timeout", parent_.stat_prefix_)).inc();
   stream_encoder_->resetStream();
   cleanup();
   callbacks_.onFailure(Http::AsyncClient::FailureReason::RequestTimemout);

test/common/http/async_client_impl_test.cc

@@ -151,6 +151,7 @@ TEST_F(AsyncClientImplTest, RequestTimeout) {
   EXPECT_CALL(stats_store_, counter("cluster.fake_cluster.upstream_rq_504"));
   EXPECT_CALL(stats_store_, counter("cluster.fake_cluster.internal.upstream_rq_5xx"));
   EXPECT_CALL(stats_store_, counter("cluster.fake_cluster.internal.upstream_rq_504"));
+  EXPECT_CALL(stats_store_, counter("cluster.fake_cluster.upstream_rq_timeout"));
   EXPECT_CALL(conn_pool_, newStream(_, _))
       .WillOnce(Invoke([&](StreamDecoder&, ConnectionPool::Callbacks& callbacks)
                            -> ConnectionPool::Cancellable* {