api_listener: improve test coverage

test/server/api_listener_test.cc

@@ -240,5 +240,147 @@ name: test_api_listener
   EXPECT_ENVOY_BUG(connection.isHalfCloseEnabled(), "Unexpected function call");
 }
 
+// Exercise SyntheticReadCallbacks unimplemented methods and PANIC behavior for socket().
+TEST_F(ApiListenerTest, SyntheticReadCallbacksUnimplementedMethods) {
+  const std::string yaml = R"EOF(
+name: test_api_listener
+address:
+  socket_address:
+    address: 127.0.0.1
+    port_value: 1234
+api_listener:
+  api_listener:
+    "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
+    stat_prefix: hcm
+    route_config:
+      name: api_router
+      virtual_hosts:
+        - name: api
+          domains:
+            - "*"
+          routes:
+            - match:
+                prefix: "/"
+              route:
+                cluster: dynamic_forward_proxy_cluster
+  )EOF";
+
+  const envoy::config::listener::v3::Listener config = parseListenerFromV3Yaml(yaml);
+  server_.server_factory_context_->cluster_manager_.initializeClusters(
+      {"dynamic_forward_proxy_cluster"}, {});
+  HttpApiListenerFactory factory;
+  auto http_api_listener = factory.create(config, server_, config.name()).value();
+  auto api_listener = http_api_listener->createHttpApiListener(server_.dispatcher());
+  ASSERT_NE(api_listener, nullptr);
+
+  // Access SyntheticReadCallbacks through the wrapper.
+  auto* wrapper = dynamic_cast<HttpApiListener::ApiListenerWrapper*>(api_listener.get());
+  ASSERT_NE(wrapper, nullptr);
+  auto& read_callbacks = wrapper->readCallbacks();
+
+  Buffer::OwnedImpl dummy_buffer("x");
+  EXPECT_ENVOY_BUG(read_callbacks.continueReading(), "Unexpected call to continueReading");
+  EXPECT_ENVOY_BUG(read_callbacks.injectReadDataToFilterChain(dummy_buffer, false),
+                   "Unexpected call to injectReadDataToFilterChain");
+  EXPECT_ENVOY_BUG(read_callbacks.disableClose(true), "Unexpected call to disableClose");
+  EXPECT_ENVOY_BUG(read_callbacks.startUpstreamSecureTransport(),
+                   "Unexpected call to startUpstreamSecureTransport");
+  EXPECT_EQ(read_callbacks.upstreamHost(), nullptr);
+  EXPECT_ENVOY_BUG(read_callbacks.upstreamHost(nullptr), "Unexpected call to upstreamHost");
+  EXPECT_DEATH(read_callbacks.socket(), "not implemented");
+}
+
+// Verify base address access and drain decision behavior.
+TEST_F(ApiListenerTest, NewStreamHandleReturnsDecoderHandle) {
+  const std::string yaml = R"EOF(
+name: test_api_listener
+address:
+  socket_address:
+    address: 127.0.0.1
+    port_value: 1234
+api_listener:
+  api_listener:
+    "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
+    stat_prefix: hcm
+    route_config:
+      name: api_router
+      virtual_hosts:
+        - name: api
+          domains:
+            - "*"
+          routes:
+            - match:
+                prefix: "/"
+              route:
+                cluster: dynamic_forward_proxy_cluster
+  )EOF";
+
+  const envoy::config::listener::v3::Listener config = parseListenerFromV3Yaml(yaml);
+  server_.server_factory_context_->cluster_manager_.initializeClusters(
+      {"dynamic_forward_proxy_cluster"}, {});
+
+  HttpApiListenerFactory factory;
+  auto http_api_listener = factory.create(config, server_, config.name()).value();
+  auto api_listener = http_api_listener->createHttpApiListener(server_.dispatcher());
+  ASSERT_NE(api_listener, nullptr);
+
+  testing::NiceMock<Envoy::Http::MockResponseEncoder> response_encoder;
+  ON_CALL(response_encoder, getStream())
+      .WillByDefault(testing::ReturnRef(response_encoder.stream_));
+  ON_CALL(response_encoder, setRequestDecoder(testing::_)).WillByDefault(testing::Return());
+
+  auto decoder_handle = api_listener->newStreamHandle(response_encoder);
+  ASSERT_NE(decoder_handle, nullptr);
+
+  // Tear down in safe order.
+  decoder_handle.reset();
+  api_listener.reset();
+}
+
+// Removing callbacks prevents receiving RemoteClose on ApiListenerWrapper destruction.
+TEST_F(ApiListenerTest, NoEventAfterCallbackRemovalOnShutdown) {
+  const std::string yaml = R"EOF(
+name: test_api_listener
+address:
+  socket_address:
+    address: 127.0.0.1
+    port_value: 1234
+api_listener:
+  api_listener:
+    "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
+    stat_prefix: hcm
+    route_config:
+      name: api_router
+      virtual_hosts:
+        - name: api
+          domains:
+            - "*"
+          routes:
+            - match:
+                prefix: "/"
+              route:
+                cluster: dynamic_forward_proxy_cluster
+  )EOF";
+
+  const envoy::config::listener::v3::Listener config = parseListenerFromV3Yaml(yaml);
+  server_.server_factory_context_->cluster_manager_.initializeClusters(
+      {"dynamic_forward_proxy_cluster"}, {});
+
+  HttpApiListenerFactory factory;
+  auto http_api_listener = factory.create(config, server_, config.name()).value();
+  auto api_listener = http_api_listener->createHttpApiListener(server_.dispatcher());
+  ASSERT_NE(api_listener, nullptr);
+
+  Network::MockConnectionCallbacks network_connection_callbacks;
+  auto& connection = dynamic_cast<HttpApiListener::ApiListenerWrapper*>(api_listener.get())
+                         ->readCallbacks()
+                         .connection();
+  connection.addConnectionCallbacks(network_connection_callbacks);
+  connection.removeConnectionCallbacks(network_connection_callbacks);
+
+  EXPECT_CALL(network_connection_callbacks, onEvent(testing::_)).Times(0);
+  api_listener.reset();
+}
+
 } // namespace Server
 } // namespace Envoy