[release-1.5] Fix opencensus tracer for sts

source/extensions/tracers/opencensus/config.cc

@@ -18,7 +18,8 @@ OpenCensusTracerFactory::OpenCensusTracerFactory() : FactoryBase(TracerNames::ge
 
 Tracing::HttpTracerPtr OpenCensusTracerFactory::createHttpTracerTyped(
     const envoy::config::trace::v3::OpenCensusConfig& proto_config, Server::Instance& server) {
-  Tracing::DriverPtr driver = std::make_unique<Driver>(proto_config, server.localInfo());
+  Tracing::DriverPtr driver =
+      std::make_unique<Driver>(proto_config, server.localInfo(), server.api());
   return std::make_unique<Tracing::HttpTracerImpl>(std::move(driver), server.localInfo());
 }
 

source/extensions/tracers/opencensus/opencensus_tracer_impl.cc

@@ -233,10 +233,43 @@ Tracing::SpanPtr Span::spawnChild(const Tracing::Config& /*config*/, const std::
 
 void Span::setSampled(bool sampled) { span_.AddAnnotation("setSampled", {{"sampled", sampled}}); }
 
+class GoogleUserProjHeaderInterceptor : public grpc::experimental::Interceptor {
+public:
+  GoogleUserProjHeaderInterceptor(const std::string& project_id) : project_id_(project_id) {}
+
+  virtual void Intercept(grpc::experimental::InterceptorBatchMethods* methods) {
+    if (methods->QueryInterceptionHookPoint(
+            grpc::experimental::InterceptionHookPoints::PRE_SEND_INITIAL_METADATA)) {
+      auto* metadata_map = methods->GetSendInitialMetadata();
+      if (metadata_map != nullptr) {
+        metadata_map->insert(std::make_pair("x-goog-user-project", project_id_));
+      }
+    }
+    methods->Proceed();
+  }
+
+private:
+  const std::string& project_id_;
+};
+
+class GoogleUserProjHeaderInterceptorFactory
+    : public grpc::experimental::ClientInterceptorFactoryInterface {
+public:
+  GoogleUserProjHeaderInterceptorFactory(const std::string& project_id) : project_id_(project_id) {}
+
+  virtual grpc::experimental::Interceptor*
+  CreateClientInterceptor(grpc::experimental::ClientRpcInfo*) override {
+    return new GoogleUserProjHeaderInterceptor(project_id_);
+  }
+
+private:
+  std::string project_id_;
+};
+
 } // namespace
 
 Driver::Driver(const envoy::config::trace::v3::OpenCensusConfig& oc_config,
-               const LocalInfo::LocalInfo& localinfo)
+               const LocalInfo::LocalInfo& localinfo, Api::Api& api)
     : oc_config_(oc_config), local_info_(localinfo) {
   if (oc_config.has_trace_config()) {
     applyTraceConfig(oc_config.trace_config());
@@ -251,8 +284,22 @@ Driver::Driver(const envoy::config::trace::v3::OpenCensusConfig& oc_config,
     sts_port = port_iter->second.string_value();
   }
   if (oc_config.stackdriver_exporter_enabled()) {
+    // Try get GCP project ID from node metadata.
+    std::string project_id;
+    auto platform_md_iter = node_metadata.fields().find("PLATFORM_METADATA");
+    if (platform_md_iter != node_metadata.fields().end()) {
+      auto platform_md = platform_md_iter->second.struct_value();
+      auto proj_id_iter = platform_md.fields().find("gcp_project");
+      if (proj_id_iter != platform_md.fields().end()) {
+        project_id = proj_id_iter->second.string_value();
+      }
+    }
     ::opencensus::exporters::trace::StackdriverOptions opts;
-    opts.project_id = oc_config.stackdriver_project_id();
+    if (!oc_config.stackdriver_project_id().empty()) {
+      opts.project_id = oc_config.stackdriver_project_id();
+    } else if (!project_id.empty()) {
+      opts.project_id = project_id;
+    }
     if (!oc_config.stackdriver_address().empty()) {
       auto channel =
           grpc::CreateChannel(oc_config.stackdriver_address(), grpc::InsecureChannelCredentials());
@@ -265,11 +312,17 @@ Driver::Driver(const envoy::config::trace::v3::OpenCensusConfig& oc_config,
       sts_options.scope = "https://www.googleapis.com/auth/cloud-platform";
       auto call_creds = grpc::experimental::StsCredentials(sts_options);
       auto ssl_creds_options = grpc::SslCredentialsOptions();
-      ssl_creds_options.pem_root_certs = "/etc/ssl/certs/ca-certificates.crt";
+      ssl_creds_options.pem_root_certs =
+          api.fileSystem().fileReadToEnd("/etc/ssl/certs/ca-certificates.crt");
       auto channel_creds = grpc::SslCredentials(ssl_creds_options);
-      auto channel =
-          ::grpc::CreateChannel("cloudtrace.googleapis.com",
-                                grpc::CompositeChannelCredentials(channel_creds, call_creds));
+      // Create an custom channel which includes an interceptor that inject user project header.
+      grpc::ChannelArguments args;
+      std::vector<std::unique_ptr<grpc::experimental::ClientInterceptorFactoryInterface>> creators;
+      creators.push_back(std::unique_ptr<GoogleUserProjHeaderInterceptorFactory>(
+          new GoogleUserProjHeaderInterceptorFactory(project_id)));
+      auto channel = ::grpc::experimental::CreateCustomChannelWithInterceptors(
+          "cloudtrace.googleapis.com", grpc::CompositeChannelCredentials(channel_creds, call_creds),
+          args, std::move(creators));
       opts.trace_service_stub = ::google::devtools::cloudtrace::v2::TraceService::NewStub(channel);
     }
     ::opencensus::exporters::trace::StackdriverExporter::Register(std::move(opts));

source/extensions/tracers/opencensus/opencensus_tracer_impl.h

@@ -1,6 +1,8 @@
 #pragma once
 
+#include "envoy/api/api.h"
 #include "envoy/config/trace/v3/trace.pb.h"
+#include "envoy/config/trace/v2/trace.pb.validate.h"
 #include "envoy/local_info/local_info.h"
 #include "envoy/tracing/http_tracer.h"
 
@@ -17,7 +19,7 @@ namespace OpenCensus {
 class Driver : public Tracing::Driver, Logger::Loggable<Logger::Id::tracing> {
 public:
   Driver(const envoy::config::trace::v3::OpenCensusConfig& oc_config,
-         const LocalInfo::LocalInfo& localinfo);
+         const LocalInfo::LocalInfo& localinfo, Api::Api& api);
 
   /**
    * Implements the abstract Driver's startSpan operation.

test/extensions/tracers/opencensus/tracer_test.cc

@@ -103,7 +103,8 @@ TEST(OpenCensusTracerTest, Span) {
   registerSpanCatcher();
   OpenCensusConfig oc_config;
   NiceMock<LocalInfo::MockLocalInfo> local_info;
-  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info));
+  Api::ApiPtr api = Api::createApiForTest();
+  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info, *api));
 
   NiceMock<Tracing::MockConfig> config;
   Http::TestHeaderMapImpl request_headers{
@@ -182,6 +183,7 @@ void testIncomingHeaders(
   registerSpanCatcher();
   OpenCensusConfig oc_config;
   NiceMock<LocalInfo::MockLocalInfo> local_info;
+  Api::ApiPtr api = Api::createApiForTest();
   oc_config.add_incoming_trace_context(OpenCensusConfig::NONE);
   oc_config.add_incoming_trace_context(OpenCensusConfig::B3);
   oc_config.add_incoming_trace_context(OpenCensusConfig::TRACE_CONTEXT);
@@ -192,7 +194,7 @@ void testIncomingHeaders(
   oc_config.add_outgoing_trace_context(OpenCensusConfig::TRACE_CONTEXT);
   oc_config.add_outgoing_trace_context(OpenCensusConfig::GRPC_TRACE_BIN);
   oc_config.add_outgoing_trace_context(OpenCensusConfig::CLOUD_TRACE_CONTEXT);
-  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info));
+  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info, *api));
   NiceMock<Tracing::MockConfig> config;
   Http::TestHeaderMapImpl request_headers{
       {":path", "/"},
@@ -279,7 +281,8 @@ namespace {
 int SamplerTestHelper(const OpenCensusConfig& oc_config) {
   registerSpanCatcher();
   NiceMock<LocalInfo::MockLocalInfo> local_info;
-  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info));
+  Api::ApiPtr api = Api::createApiForTest();
+  std::unique_ptr<Tracing::Driver> driver(new OpenCensus::Driver(oc_config, local_info, *api));
   auto span = ::opencensus::trace::Span::StartSpan("test_span");
   span.End();
   // Retrieve SpanData from the OpenCensus trace exporter.