Supply x-envoy-downstream-service-node HTTP header to the upstream when needed

docs/configuration/http_conn_man/headers.rst

@@ -51,6 +51,15 @@ authentication TLS mesh which will make this header fully secure. Like *user-age
 is determined by the :option:`--service-cluster` command line option. In order to enable this
 feature you need to set the :ref:`user_agent <config_http_conn_man_add_user_agent>` option to true.
 
+.. _config_http_conn_man_headers_downstream-service-node:
+
+x-envoy-downstream-service-node
+-------------------------------
+
+Internal services may want to know the downstream node request comes from. This header
+is quite similar to :ref:`config_http_conn_man_headers_downstream-service-cluster`, except the value is taken from
+the  :option:`--service-node` option.
+
 .. _config_http_conn_man_headers_x-envoy-external-address:
 
 x-envoy-external-address

include/envoy/http/header_map.h

@@ -197,6 +197,7 @@ class HeaderEntry {
   HEADER_FUNC(ContentType)                                                                         \
   HEADER_FUNC(Date)                                                                                \
   HEADER_FUNC(EnvoyDownstreamServiceCluster)                                                       \
+  HEADER_FUNC(EnvoyDownstreamServiceNode)                                                          \
   HEADER_FUNC(EnvoyExpectedRequestTimeoutMs)                                                       \
   HEADER_FUNC(EnvoyExternalAddress)                                                                \
   HEADER_FUNC(EnvoyForceTrace)                                                                     \

source/common/http/BUILD

@@ -104,6 +104,7 @@ envoy_cc_library(
         "//include/envoy/http:codec_interface",
         "//include/envoy/http:filter_interface",
         "//include/envoy/http:header_map_interface",
+        "//include/envoy/local_info:local_info_interface",
         "//include/envoy/network:connection_interface",
         "//include/envoy/network:drain_decision_interface",
         "//include/envoy/network:filter_interface",

source/common/http/conn_manager_impl.cc

@@ -50,11 +50,12 @@ ConnectionManagerTracingStats ConnectionManagerImpl::generateTracingStats(const
 ConnectionManagerImpl::ConnectionManagerImpl(ConnectionManagerConfig& config,
                                              Network::DrainDecision& drain_close,
                                              Runtime::RandomGenerator& random_generator,
-                                             Tracing::HttpTracer& tracer, Runtime::Loader& runtime)
+                                             Tracing::HttpTracer& tracer, Runtime::Loader& runtime,
+                                             const LocalInfo::LocalInfo& local_info)
     : config_(config), stats_(config_.stats()),
       conn_length_(stats_.named_.downstream_cx_length_ms_.allocateSpan()),
       drain_close_(drain_close), random_generator_(random_generator), tracer_(tracer),
-      runtime_(runtime) {}
+      runtime_(runtime), local_info_(local_info) {}
 
 void ConnectionManagerImpl::initializeReadFilterCallbacks(Network::ReadFilterCallbacks& callbacks) {
   read_callbacks_ = &callbacks;
@@ -465,7 +466,7 @@ void ConnectionManagerImpl::ActiveStream::decodeHeaders(HeaderMapPtr&& headers,
   ConnectionManagerUtility::mutateRequestHeaders(
       *request_headers_, connection_manager_.read_callbacks_->connection(),
       connection_manager_.config_, *snapped_route_config_, connection_manager_.random_generator_,
-      connection_manager_.runtime_);
+      connection_manager_.runtime_, connection_manager_.local_info_);
 
   // Check if tracing is enabled at all.
   if (connection_manager_.config_.tracingConfig()) {

source/common/http/conn_manager_impl.h

@@ -229,7 +229,7 @@ class ConnectionManagerImpl : Logger::Loggable<Logger::Id::http>,
 public:
   ConnectionManagerImpl(ConnectionManagerConfig& config, Network::DrainDecision& drain_close,
                         Runtime::RandomGenerator& random_generator, Tracing::HttpTracer& tracer,
-                        Runtime::Loader& runtime);
+                        Runtime::Loader& runtime, const LocalInfo::LocalInfo& local_info);
   ~ConnectionManagerImpl();
 
   static ConnectionManagerStats generateStats(const std::string& prefix, Stats::Store& stats);
@@ -504,6 +504,7 @@ class ConnectionManagerImpl : Logger::Loggable<Logger::Id::http>,
   Runtime::RandomGenerator& random_generator_;
   Tracing::HttpTracer& tracer_;
   Runtime::Loader& runtime_;
+  const LocalInfo::LocalInfo& local_info_;
   Network::ReadFilterCallbacks* read_callbacks_{};
 };
 

source/common/http/conn_manager_utility.cc

@@ -32,7 +32,8 @@ void ConnectionManagerUtility::mutateRequestHeaders(Http::HeaderMap& request_hea
                                                     ConnectionManagerConfig& config,
                                                     const Router::Config& route_config,
                                                     Runtime::RandomGenerator& random,
-                                                    Runtime::Loader& runtime) {
+                                                    Runtime::Loader& runtime,
+                                                    const LocalInfo::LocalInfo& local_info) {
   // Clean proxy headers.
   request_headers.removeConnection();
   request_headers.removeEnvoyInternalRequest();
@@ -76,6 +77,7 @@ void ConnectionManagerUtility::mutateRequestHeaders(Http::HeaderMap& request_hea
   } else {
     if (edge_request) {
       request_headers.removeEnvoyDownstreamServiceCluster();
+      request_headers.removeEnvoyDownstreamServiceNode();
     }
 
     request_headers.removeEnvoyRetryOn();
@@ -97,6 +99,10 @@ void ConnectionManagerUtility::mutateRequestHeaders(Http::HeaderMap& request_hea
     if (user_agent_header.value().empty()) {
       user_agent_header.value(config.userAgent().value());
     }
+
+    if (!local_info.nodeName().empty()) {
+      request_headers.insertEnvoyDownstreamServiceNode().value(local_info.nodeName());
+    }
   }
 
   // If we are an external request, AND we are "using remote address" (see above), we set

source/common/http/conn_manager_utility.h

@@ -22,7 +22,8 @@ class ConnectionManagerUtility {
   static void mutateRequestHeaders(Http::HeaderMap& request_headers,
                                    Network::Connection& connection, ConnectionManagerConfig& config,
                                    const Router::Config& route_config,
-                                   Runtime::RandomGenerator& random, Runtime::Loader& runtime);
+                                   Runtime::RandomGenerator& random, Runtime::Loader& runtime,
+                                   const LocalInfo::LocalInfo& local_info);
 
   static void mutateResponseHeaders(Http::HeaderMap& response_headers,
                                     const Http::HeaderMap& request_headers,

source/common/http/headers.h

@@ -23,6 +23,7 @@ class HeaderValues {
   const LowerCaseString Cookie{"cookie"};
   const LowerCaseString Date{"date"};
   const LowerCaseString EnvoyDownstreamServiceCluster{"x-envoy-downstream-service-cluster"};
+  const LowerCaseString EnvoyDownstreamServiceNode{"x-envoy-downstream-service-node"};
   const LowerCaseString EnvoyExternalAddress{"x-envoy-external-address"};
   const LowerCaseString EnvoyForceTrace{"x-envoy-force-trace"};
   const LowerCaseString EnvoyInternalRequest{"x-envoy-internal"};

source/server/config/network/http_connection_manager.cc

@@ -36,9 +36,9 @@ NetworkFilterFactoryCb HttpConnectionManagerFilterConfigFactory::createFilterFac
   std::shared_ptr<HttpConnectionManagerConfig> http_config(
       new HttpConnectionManagerConfig(config, server));
   return [http_config, &server](Network::FilterManager& filter_manager) mutable -> void {
-    filter_manager.addReadFilter(Network::ReadFilterSharedPtr{
-        new Http::ConnectionManagerImpl(*http_config, server.drainManager(), server.random(),
-                                        server.httpTracer(), server.runtime())});
+    filter_manager.addReadFilter(Network::ReadFilterSharedPtr{new Http::ConnectionManagerImpl(
+        *http_config, server.drainManager(), server.random(), server.httpTracer(), server.runtime(),
+        server.localInfo())});
   };
 }
 

source/server/http/admin.cc

@@ -382,7 +382,8 @@ Http::ServerConnectionPtr AdminImpl::createCodec(Network::Connection& connection
 
 bool AdminImpl::createFilterChain(Network::Connection& connection) {
   connection.addReadFilter(Network::ReadFilterSharedPtr{new Http::ConnectionManagerImpl(
-      *this, server_.drainManager(), server_.random(), server_.httpTracer(), server_.runtime())});
+      *this, server_.drainManager(), server_.random(), server_.httpTracer(), server_.runtime(),
+      server_.localInfo())});
   return true;
 }
 

test/common/http/BUILD

@@ -98,6 +98,7 @@ envoy_cc_test(
         "//test/mocks/access_log:access_log_mocks",
         "//test/mocks/buffer:buffer_mocks",
         "//test/mocks/http:http_mocks",
+        "//test/mocks/local_info:local_info_mocks",
         "//test/mocks/network:network_mocks",
         "//test/mocks/runtime:runtime_mocks",
         "//test/mocks/ssl:ssl_mocks",
@@ -118,6 +119,7 @@ envoy_cc_test(
         "//source/common/runtime:runtime_lib",
         "//source/common/runtime:uuid_util_lib",
         "//test/mocks/http:http_mocks",
+        "//test/mocks/local_info:local_info_mocks",
         "//test/mocks/network:network_mocks",
         "//test/mocks/runtime:runtime_mocks",
         "//test/mocks/upstream:upstream_mocks",

test/common/http/conn_manager_impl_test.cc

@@ -24,6 +24,7 @@
 #include "test/mocks/buffer/mocks.h"
 #include "test/mocks/common.h"
 #include "test/mocks/http/mocks.h"
+#include "test/mocks/local_info/mocks.h"
 #include "test/mocks/network/mocks.h"
 #include "test/mocks/runtime/mocks.h"
 #include "test/mocks/ssl/mocks.h"
@@ -89,7 +90,8 @@ class HttpConnectionManagerImplTest : public Test, public ConnectionManagerConfi
     ON_CALL(filter_callbacks_.connection_, ssl()).WillByDefault(Return(ssl_connection_.get()));
     ON_CALL(filter_callbacks_.connection_, remoteAddress())
         .WillByDefault(ReturnRef(remote_address_));
-    conn_manager_.reset(new ConnectionManagerImpl(*this, drain_close_, random_, tracer_, runtime_));
+    conn_manager_.reset(
+        new ConnectionManagerImpl(*this, drain_close_, random_, tracer_, runtime_, local_info_));
     conn_manager_->initializeReadFilterCallbacks(filter_callbacks_);
   }
 
@@ -177,6 +179,7 @@ class HttpConnectionManagerImplTest : public Test, public ConnectionManagerConfi
   Optional<std::string> user_agent_;
   Optional<std::chrono::milliseconds> idle_timeout_;
   NiceMock<Runtime::MockRandomGenerator> random_;
+  NiceMock<LocalInfo::MockLocalInfo> local_info_;
   std::unique_ptr<Ssl::MockConnection> ssl_connection_;
   RouteConfigProvider route_config_provider_;
   TracingConnectionManagerConfigPtr tracing_config_;