weighted cluster: add header mutation integrations tests for weighted clusters (#40857)

Commit Message:
Additional Description:
Risk Level: low
Testing: added integration tests
Docs Changes:
Release Notes:

---------

Signed-off-by: Boteng Yao <[email protected]>

Author: botengyao

source/extensions/filters/http/header_mutation/BUILD

@@ -28,6 +28,9 @@ envoy_cc_extension(
     name = "config",
     srcs = ["config.cc"],
     hdrs = ["config.h"],
+    extra_visibility = [
+        "//test/integration:__subpackages__",
+    ],
     deps = [
         ":header_mutation_lib",
         "//envoy/registry",

test/integration/BUILD

@@ -2736,9 +2736,11 @@ envoy_cc_test(
     deps = [
         ":http_integration_lib",
         ":integration_lib",
+        "//source/extensions/filters/http/header_mutation:config",
         "//test/integration/filters:repick_cluster_filter_lib",
         "@envoy_api//envoy/config/bootstrap/v3:pkg_cc_proto",
         "@envoy_api//envoy/config/route/v3:pkg_cc_proto",
+        "@envoy_api//envoy/extensions/filters/http/header_mutation/v3:pkg_cc_proto",
         "@envoy_api//envoy/extensions/filters/network/http_connection_manager/v3:pkg_cc_proto",
     ],
 )

test/integration/weighted_cluster_integration_test.cc

@@ -4,6 +4,7 @@
 
 #include "envoy/config/bootstrap/v3/bootstrap.pb.h"
 #include "envoy/config/route/v3/route_components.pb.h"
+#include "envoy/extensions/filters/http/header_mutation/v3/header_mutation.pb.h"
 #include "envoy/extensions/filters/network/http_connection_manager/v3/http_connection_manager.pb.h"
 
 #include "test/integration/filters/repick_cluster_filter.h"
@@ -28,7 +29,7 @@ class WeightedClusterIntegrationTest : public testing::TestWithParam<Network::Ad
     }
   }
 
-  void initializeConfig(const std::vector<uint64_t>& weights) {
+  void initializeConfig(const std::vector<uint64_t>& weights, bool test_header_mutation = false) {
     // Set the cluster configuration for `cluster_1`
     config_helper_.addConfigModifier([](envoy::config::bootstrap::v3::Bootstrap& bootstrap) {
       auto* cluster = bootstrap.mutable_static_resources()->add_clusters();
@@ -39,10 +40,13 @@ class WeightedClusterIntegrationTest : public testing::TestWithParam<Network::Ad
 
     // Add the custom filter.
     config_helper_.addFilter("name: repick-cluster-filter");
+    if (test_header_mutation) {
+      config_helper_.addFilter("name: envoy.filters.http.header_mutation");
+    }
 
     // Modify route with weighted cluster configuration.
     config_helper_.addConfigModifier(
-        [&weights](
+        [&weights, &test_header_mutation](
             envoy::extensions::filters::network::http_connection_manager::v3::HttpConnectionManager&
                 hcm) {
           auto* weighted_clusters = hcm.mutable_route_config()
@@ -56,6 +60,28 @@ class WeightedClusterIntegrationTest : public testing::TestWithParam<Network::Ad
           cluster->set_name("cluster_0");
           cluster->mutable_weight()->set_value(weights[0]);
 
+          if (test_header_mutation) {
+            envoy::config::core::v3::HeaderValueOption* header_value_option =
+                cluster->mutable_request_headers_to_add()->Add();
+            auto* mutable_header = header_value_option->mutable_header();
+            mutable_header->set_key("x-cluster-name-test");
+            mutable_header->set_value("cluster_0");
+
+            envoy::extensions::filters::http::header_mutation::v3::HeaderMutationPerRoute
+                header_mutation;
+            std::string header_mutation_config = R"EOF(
+              mutations:
+                response_mutations:
+                - append:
+                    header:
+                      key: "x-cluster-header-mutation-test"
+                      value: "cluster-0"
+            )EOF";
+            TestUtility::loadFromYaml(header_mutation_config, header_mutation);
+            (*cluster->mutable_typed_per_filter_config())["envoy.filters.http.header_mutation"]
+                .PackFrom(header_mutation);
+          }
+
           // Add a cluster with `cluster_header` specified.
           cluster = weighted_clusters->add_clusters();
           cluster->set_cluster_header(std::string(Envoy::RepickClusterFilter::ClusterHeaderName));
@@ -67,7 +93,8 @@ class WeightedClusterIntegrationTest : public testing::TestWithParam<Network::Ad
 
   const std::vector<uint64_t>& getDefaultWeights() { return default_weights_; }
 
-  void sendRequestAndValidateResponse(const std::vector<uint64_t>& upstream_indices) {
+  void sendRequestAndValidateResponse(const std::vector<uint64_t>& upstream_indices,
+                                      bool check_header_mutation = false) {
     // Create a client aimed at Envoy’s default HTTP port.
     codec_client_ = makeHttpConnection(makeClientConnection((lookupPort("http"))));
 
@@ -86,6 +113,14 @@ class WeightedClusterIntegrationTest : public testing::TestWithParam<Network::Ad
     // Verify the proxied request was received upstream, as expected.
     EXPECT_TRUE(upstream_request_->complete());
     EXPECT_EQ(0U, upstream_request_->bodyLength());
+    if (check_header_mutation) {
+      EXPECT_EQ(
+          upstream_request_->headers().get(Http::LowerCaseString("x-cluster-name-test")).size(), 1);
+      EXPECT_EQ(result.response->headers()
+                    .get(Http::LowerCaseString("x-cluster-header-mutation-test"))
+                    .size(),
+                1);
+    }
     // Verify the proxied response was received downstream, as expected.
     EXPECT_TRUE(result.response->complete());
     EXPECT_EQ("200", result.response->headers().getStatusValue());
@@ -121,6 +156,19 @@ TEST_P(WeightedClusterIntegrationTest, SteerTrafficToOneClusterWithName) {
   EXPECT_EQ(test_server_->counter("cluster.cluster_0.upstream_cx_total")->value(), 1);
 }
 
+// Test the header mutations in weighted clusters.
+TEST_P(WeightedClusterIntegrationTest, SteerTrafficToOneClusterWithHeaderMutation) {
+  setDeterministicValue();
+  initializeConfig(getDefaultWeights(), true);
+
+  // The expected destination cluster upstream is index 0 since the selected
+  // value is set to 0 indirectly via `setDeterministicValue()` above to set the weight to 0.
+  sendRequestAndValidateResponse({0}, true);
+
+  // Check that the expected upstream cluster has incoming request.
+  EXPECT_EQ(test_server_->counter("cluster.cluster_0.upstream_cx_total")->value(), 1);
+}
+
 // Steer the traffic (i.e. send the request) to the weighted cluster with `cluster_header`
 // specified.
 TEST_P(WeightedClusterIntegrationTest, SteerTrafficToOneClusterWithHeader) {