opentelemetry tracer: add support for environment resource detector

api/BUILD

@@ -306,6 +306,7 @@ proto_library(
         "//envoy/extensions/stat_sinks/graphite_statsd/v3:pkg",
         "//envoy/extensions/stat_sinks/open_telemetry/v3:pkg",
         "//envoy/extensions/stat_sinks/wasm/v3:pkg",
+        "//envoy/extensions/tracers/opentelemetry/resource_detectors/v3:pkg",
         "//envoy/extensions/transport_sockets/alts/v3:pkg",
         "//envoy/extensions/transport_sockets/http_11_proxy/v3:pkg",
         "//envoy/extensions/transport_sockets/internal_upstream/v3:pkg",

api/envoy/config/trace/v3/opentelemetry.proto

@@ -2,6 +2,7 @@ syntax = "proto3";
 
 package envoy.config.trace.v3;
 
+import "envoy/config/core/v3/extension.proto";
 import "envoy/config/core/v3/grpc_service.proto";
 import "envoy/config/core/v3/http_service.proto";
 
@@ -43,4 +44,8 @@ message OpenTelemetryConfig {
   // The name for the service. This will be populated in the ResourceSpan Resource attributes.
   // If it is not provided, it will default to "unknown_service:envoy".
   string service_name = 2;
+
+  // An ordered list of resource detectors
+  // [#extension-category: envoy.tracers.opentelemetry.resource_detectors]
+  repeated core.v3.TypedExtensionConfig resource_detectors = 4;
 }

api/envoy/extensions/tracers/opentelemetry/resource_detectors/v3/BUILD

@@ -0,0 +1,9 @@
+# DO NOT EDIT. This file is generated by tools/proto_format/proto_sync.py.
+
+load("@envoy_api//bazel:api_build_system.bzl", "api_proto_package")
+
+licenses(["notice"])  # Apache 2
+
+api_proto_package(
+    deps = ["@com_github_cncf_udpa//udpa/annotations:pkg"],
+)

api/envoy/extensions/tracers/opentelemetry/resource_detectors/v3/environment_resource_detector.proto

@@ -0,0 +1,25 @@
+syntax = "proto3";
+
+package envoy.extensions.tracers.opentelemetry.resource_detectors.v3;
+
+import "udpa/annotations/status.proto";
+
+option java_package = "io.envoyproxy.envoy.extensions.tracers.opentelemetry.resource_detectors.v3";
+option java_outer_classname = "EnvironmentResourceDetectorProto";
+option java_multiple_files = true;
+option go_package = "github.com/envoyproxy/go-control-plane/envoy/extensions/tracers/opentelemetry/resource_detectors/v3;resource_detectorsv3";
+option (udpa.annotations.file_status).package_version_status = ACTIVE;
+
+// [#protodoc-title: Environment Resource Detector config]
+
+// Configuration for the Environment Resource detector extension.
+// The resource detector reads from the ``OTEL_RESOURCE_ATTRIBUTES``
+// environment variable, as per the OpenTelemetry specification.
+//
+// See:
+//
+// `OpenTelemetry specification <https://github.com/open-telemetry/opentelemetry-specification/blob/v1.24.0/specification/resource/sdk.md#detecting-resource-information-from-the-environment>`_
+//
+// [#extension: envoy.tracers.opentelemetry.resource_detectors.environment]
+message EnvironmentResourceDetectorConfig {
+}

api/versioning/BUILD

@@ -245,6 +245,7 @@ proto_library(
         "//envoy/extensions/stat_sinks/graphite_statsd/v3:pkg",
         "//envoy/extensions/stat_sinks/open_telemetry/v3:pkg",
         "//envoy/extensions/stat_sinks/wasm/v3:pkg",
+        "//envoy/extensions/tracers/opentelemetry/resource_detectors/v3:pkg",
         "//envoy/extensions/transport_sockets/alts/v3:pkg",
         "//envoy/extensions/transport_sockets/http_11_proxy/v3:pkg",
         "//envoy/extensions/transport_sockets/internal_upstream/v3:pkg",

changelogs/current.yaml

@@ -32,5 +32,8 @@ removed_config_or_runtime:
     runtime flag and legacy code path.
 
 new_features:
+- area: tracing
+  change: |
+    Added support for configuring resource detectors on the OpenTelemetry tracer.
 
 deprecated:

docs/root/api-v3/config/trace/opentelemetry/resource_detectors.rst

@@ -0,0 +1,10 @@
+OpenTelemetry Resource Detectors
+================================
+
+Resource detectors that can be configured with the OpenTelemetry Tracer:
+
+.. toctree::
+  :glob:
+  :maxdepth: 3
+
+  ../../../extensions/tracers/opentelemetry/resource_detectors/v3/*

docs/root/api-v3/config/trace/trace.rst

@@ -12,3 +12,4 @@ HTTP tracers
   :maxdepth: 2
 
   v3/*
+  opentelemetry/resource_detectors

source/extensions/extensions_build_config.bzl

@@ -265,6 +265,12 @@ EXTENSIONS = {
     "envoy.tracers.skywalking":                         "//source/extensions/tracers/skywalking:config",
     "envoy.tracers.opentelemetry":                      "//source/extensions/tracers/opentelemetry:config",
 
+    #
+    # OpenTelemetry Resource Detectors
+    #
+
+    "envoy.tracers.opentelemetry.resource_detectors.environment":         "//source/extensions/tracers/opentelemetry/resource_detectors/environment:config",
+
     #
     # Transport sockets
     #

source/extensions/extensions_metadata.yaml

@@ -1676,3 +1676,10 @@ envoy.filters.network.set_filter_state:
   status: alpha
   type_urls:
   - envoy.extensions.filters.network.set_filter_state.v3.Config
+envoy.tracers.opentelemetry.resource_detectors.environment:
+  categories:
+  - envoy.tracers.opentelemetry.resource_detectors
+  security_posture: unknown
+  status: wip
+  type_urls:
+  - envoy.extensions.tracers.opentelemetry.resource_detectors.v3.EnvironmentResourceDetectorConfig

source/extensions/tracers/opentelemetry/BUILD

@@ -41,6 +41,7 @@ envoy_cc_library(
         "//source/common/config:utility_lib",
         "//source/common/tracing:http_tracer_lib",
         "//source/extensions/tracers/common:factory_base_lib",
+        "//source/extensions/tracers/opentelemetry/resource_detectors:resource_detector_lib",
         "@envoy_api//envoy/config/trace/v3:pkg_cc_proto",
         "@opentelemetry_proto//:trace_cc_proto",
     ],

source/extensions/tracers/opentelemetry/opentelemetry_tracer_impl.cc

@@ -10,6 +10,8 @@
 #include "source/common/tracing/http_tracer_impl.h"
 #include "source/extensions/tracers/opentelemetry/grpc_trace_exporter.h"
 #include "source/extensions/tracers/opentelemetry/http_trace_exporter.h"
+#include "source/extensions/tracers/opentelemetry/resource_detectors/resource_detector.h"
+#include "source/extensions/tracers/opentelemetry/resource_detectors/resource_provider.h"
 #include "source/extensions/tracers/opentelemetry/span_context.h"
 #include "source/extensions/tracers/opentelemetry/span_context_extractor.h"
 #include "source/extensions/tracers/opentelemetry/trace_exporter.h"
@@ -25,19 +27,28 @@ namespace OpenTelemetry {
 
 Driver::Driver(const envoy::config::trace::v3::OpenTelemetryConfig& opentelemetry_config,
                Server::Configuration::TracerFactoryContext& context)
+    : Driver(opentelemetry_config, context, ResourceProviderImpl{}) {}
+
+Driver::Driver(const envoy::config::trace::v3::OpenTelemetryConfig& opentelemetry_config,
+               Server::Configuration::TracerFactoryContext& context,
+               const ResourceProvider& resource_provider)
     : tls_slot_ptr_(context.serverFactoryContext().threadLocal().allocateSlot()),
       tracing_stats_{OPENTELEMETRY_TRACER_STATS(
           POOL_COUNTER_PREFIX(context.serverFactoryContext().scope(), "tracing.opentelemetry"))} {
   auto& factory_context = context.serverFactoryContext();
 
+  Resource resource = resource_provider.getResource(opentelemetry_config, context);
+  ResourceConstSharedPtr resource_ptr = std::make_shared<Resource>(std::move(resource));
+
   if (opentelemetry_config.has_grpc_service() && opentelemetry_config.has_http_service()) {
     throw EnvoyException(
         "OpenTelemetry Tracer cannot have both gRPC and HTTP exporters configured. "
         "OpenTelemetry tracer will be disabled.");
   }
 
   // Create the tracer in Thread Local Storage.
-  tls_slot_ptr_->set([opentelemetry_config, &factory_context, this](Event::Dispatcher& dispatcher) {
+  tls_slot_ptr_->set([opentelemetry_config, &factory_context, this,
+                      resource_ptr](Event::Dispatcher& dispatcher) {
     OpenTelemetryTraceExporterPtr exporter;
     if (opentelemetry_config.has_grpc_service()) {
       Grpc::AsyncClientFactoryPtr&& factory =
@@ -52,7 +63,7 @@ Driver::Driver(const envoy::config::trace::v3::OpenTelemetryConfig& opentelemetr
     }
     TracerPtr tracer = std::make_unique<Tracer>(
         std::move(exporter), factory_context.timeSource(), factory_context.api().randomGenerator(),
-        factory_context.runtime(), dispatcher, tracing_stats_, opentelemetry_config.service_name());
+        factory_context.runtime(), dispatcher, tracing_stats_, resource_ptr);
 
     return std::make_shared<TlsTracer>(std::move(tracer));
   });

source/extensions/tracers/opentelemetry/opentelemetry_tracer_impl.h

@@ -8,6 +8,8 @@
 #include "source/common/common/logger.h"
 #include "source/common/singleton/const_singleton.h"
 #include "source/extensions/tracers/common/factory_base.h"
+#include "source/extensions/tracers/opentelemetry/grpc_trace_exporter.h"
+#include "source/extensions/tracers/opentelemetry/resource_detectors/resource_provider.h"
 #include "source/extensions/tracers/opentelemetry/tracer.h"
 
 namespace Envoy {
@@ -31,6 +33,10 @@ class Driver : Logger::Loggable<Logger::Id::tracing>, public Tracing::Driver {
   Driver(const envoy::config::trace::v3::OpenTelemetryConfig& opentelemetry_config,
          Server::Configuration::TracerFactoryContext& context);
 
+  Driver(const envoy::config::trace::v3::OpenTelemetryConfig& opentelemetry_config,
+         Server::Configuration::TracerFactoryContext& context,
+         const ResourceProvider& resource_provider);
+
   // Tracing::Driver
   Tracing::SpanPtr startSpan(const Tracing::Config& config, Tracing::TraceContext& trace_context,
                              const StreamInfo::StreamInfo& stream_info,

source/extensions/tracers/opentelemetry/resource_detectors/BUILD

@@ -0,0 +1,27 @@
+load(
+    "//bazel:envoy_build_system.bzl",
+    "envoy_cc_library",
+    "envoy_extension_package",
+)
+
+licenses(["notice"])  # Apache 2
+
+envoy_extension_package()
+
+envoy_cc_library(
+    name = "resource_detector_lib",
+    srcs = [
+        "resource_provider.cc",
+    ],
+    hdrs = [
+        "resource_detector.h",
+        "resource_provider.h",
+    ],
+    deps = [
+        "//envoy/config:typed_config_interface",
+        "//envoy/server:tracer_config_interface",
+        "//source/common/common:logger_lib",
+        "//source/common/config:utility_lib",
+        "@envoy_api//envoy/config/trace/v3:pkg_cc_proto",
+    ],
+)

source/extensions/tracers/opentelemetry/resource_detectors/environment/BUILD

@@ -0,0 +1,33 @@
+load(
+    "//bazel:envoy_build_system.bzl",
+    "envoy_cc_extension",
+    "envoy_cc_library",
+    "envoy_extension_package",
+)
+
+licenses(["notice"])  # Apache 2
+
+envoy_extension_package()
+
+envoy_cc_extension(
+    name = "config",
+    srcs = ["config.cc"],
+    hdrs = ["config.h"],
+    deps = [
+        ":environment_resource_detector_lib",
+        "//envoy/registry",
+        "//source/common/config:utility_lib",
+        "@envoy_api//envoy/extensions/tracers/opentelemetry/resource_detectors/v3:pkg_cc_proto",
+    ],
+)
+
+envoy_cc_library(
+    name = "environment_resource_detector_lib",
+    srcs = ["environment_resource_detector.cc"],
+    hdrs = ["environment_resource_detector.h"],
+    deps = [
+        "//source/common/config:datasource_lib",
+        "//source/extensions/tracers/opentelemetry/resource_detectors:resource_detector_lib",
+        "@envoy_api//envoy/extensions/tracers/opentelemetry/resource_detectors/v3:pkg_cc_proto",
+    ],
+)

source/extensions/tracers/opentelemetry/resource_detectors/environment/config.cc

@@ -0,0 +1,35 @@
+#include "source/extensions/tracers/opentelemetry/resource_detectors/environment/config.h"
+
+#include "envoy/extensions/tracers/opentelemetry/resource_detectors/v3/environment_resource_detector.pb.h"
+#include "envoy/extensions/tracers/opentelemetry/resource_detectors/v3/environment_resource_detector.pb.validate.h"
+
+#include "source/common/config/utility.h"
+#include "source/extensions/tracers/opentelemetry/resource_detectors/environment/environment_resource_detector.h"
+
+namespace Envoy {
+namespace Extensions {
+namespace Tracers {
+namespace OpenTelemetry {
+
+ResourceDetectorPtr EnvironmentResourceDetectorFactory::createResourceDetector(
+    const Protobuf::Message& message, Server::Configuration::TracerFactoryContext& context) {
+
+  auto mptr = Envoy::Config::Utility::translateAnyToFactoryConfig(
+      dynamic_cast<const ProtobufWkt::Any&>(message), context.messageValidationVisitor(), *this);
+
+  const auto& proto_config = MessageUtil::downcastAndValidate<
+      const envoy::extensions::tracers::opentelemetry::resource_detectors::v3::
+          EnvironmentResourceDetectorConfig&>(*mptr, context.messageValidationVisitor());
+
+  return std::make_unique<EnvironmentResourceDetector>(proto_config, context);
+}
+
+/**
+ * Static registration for the Env resource detector factory. @see RegisterFactory.
+ */
+REGISTER_FACTORY(EnvironmentResourceDetectorFactory, ResourceDetectorFactory);
+
+} // namespace OpenTelemetry
+} // namespace Tracers
+} // namespace Extensions
+} // namespace Envoy

source/extensions/tracers/opentelemetry/resource_detectors/environment/config.h

@@ -0,0 +1,46 @@
+#pragma once
+
+#include <string>
+
+#include "envoy/extensions/tracers/opentelemetry/resource_detectors/v3/environment_resource_detector.pb.h"
+
+#include "source/extensions/tracers/opentelemetry/resource_detectors/resource_detector.h"
+
+namespace Envoy {
+namespace Extensions {
+namespace Tracers {
+namespace OpenTelemetry {
+
+/**
+ * Config registration for the Environment resource detector. @see ResourceDetectorFactory.
+ */
+class EnvironmentResourceDetectorFactory : public ResourceDetectorFactory {
+public:
+  /**
+   * @brief Create a Resource Detector that reads from the OTEL_RESOURCE_ATTRIBUTES
+   * environment variable.
+   *
+   * @param message The resource detector configuration.
+   * @param context The tracer factory context.
+   * @return ResourceDetectorPtr
+   */
+  ResourceDetectorPtr
+  createResourceDetector(const Protobuf::Message& message,
+                         Server::Configuration::TracerFactoryContext& context) override;
+
+  ProtobufTypes::MessagePtr createEmptyConfigProto() override {
+    return std::make_unique<envoy::extensions::tracers::opentelemetry::resource_detectors::v3::
+                                EnvironmentResourceDetectorConfig>();
+  }
+
+  std::string name() const override {
+    return "envoy.tracers.opentelemetry.resource_detectors.environment";
+  }
+};
+
+DECLARE_FACTORY(EnvironmentResourceDetectorFactory);
+
+} // namespace OpenTelemetry
+} // namespace Tracers
+} // namespace Extensions
+} // namespace Envoy

source/extensions/tracers/opentelemetry/resource_detectors/environment/environment_resource_detector.cc

@@ -0,0 +1,60 @@
+#include "environment_resource_detector.h"
+
+#include <sstream>
+#include <string>
+
+#include "source/common/config/datasource.h"
+#include "source/extensions/tracers/opentelemetry/resource_detectors/resource_detector.h"
+
+namespace Envoy {
+namespace Extensions {
+namespace Tracers {
+namespace OpenTelemetry {
+
+constexpr absl::string_view kOtelResourceAttributesEnv = "OTEL_RESOURCE_ATTRIBUTES";
+
+/**
+ * @brief Detects a resource from the OTEL_RESOURCE_ATTRIBUTES environment variable
+ * Based on the OTel C++ SDK:
+ * https://github.com/open-telemetry/opentelemetry-cpp/blob/v1.11.0/sdk/src/resource/resource_detector.cc
+ *
+ * @return Resource A resource with the attributes from the OTEL_RESOURCE_ATTRIBUTES environment
+ * variable.
+ */
+Resource EnvironmentResourceDetector::detect() {
+  envoy::config::core::v3::DataSource ds;
+  ds.set_environment_variable(kOtelResourceAttributesEnv);
+
+  Resource resource;
+  resource.schemaUrl_ = "";
+  std::string attributes_str = "";
+
+  attributes_str = Config::DataSource::read(ds, true, context_.serverFactoryContext().api());
+
+  if (attributes_str.empty()) {
+    throw EnvoyException(
+        fmt::format("The OpenTelemetry environment resource detector is configured but the '{}'"
+                    " environment variable is empty.",
+                    kOtelResourceAttributesEnv));
+  }
+
+  for (const auto& pair : StringUtil::splitToken(attributes_str, ",")) {
+    const auto keyValue = StringUtil::splitToken(pair, "=");
+    if (keyValue.size() != 2) {
+      throw EnvoyException(
+          fmt::format("The OpenTelemetry environment resource detector is configured but the '{}'"
+                      " environment variable has an invalid format.",
+                      kOtelResourceAttributesEnv));
+    }
+
+    const std::string key = std::string(keyValue[0]);
+    const std::string value = std::string(keyValue[1]);
+    resource.attributes_[key] = value;
+  }
+  return resource;
+}
+
+} // namespace OpenTelemetry
+} // namespace Tracers
+} // namespace Extensions
+} // namespace Envoy