commit1

Author: anna-git

include/datadog/config.h

@@ -56,21 +56,26 @@ struct ConfigMetadata {
       : name(n), value(std::move(v)), origin(orig), error(std::move(err)) {}
 };
 
-// Return a pair containing the configuration origin and value of a
-// configuration value chosen from one of the specified `from_env`,
-// `from_config`, and `fallback`. This function defines the relative precedence
-// among configuration values originating from the environment, programmatic
-// configuration, and default configuration.
+// Return a vector containing the configuration values chosen from one of the 
+// specified `from_env`, `from_user`, and `fallback`. This function defines 
+// the relative precedence among configuration values, from lower to higher, 
+// originating from the default configuration, programmatic configuration, 
+// and environment.
 template <typename Value, typename DefaultValue>
-std::pair<ConfigMetadata::Origin, Value> pick(const Optional<Value> &from_env,
-                                              const Optional<Value> &from_user,
-                                              DefaultValue fallback) {
+std::vector<std::pair<ConfigMetadata::Origin, Value>> pick(
+    const Optional<Value>& from_env, const Optional<Value>& from_user,
+    DefaultValue fallback) {
+  std::vector<std::pair<ConfigMetadata::Origin, Value>> result;
+  result.emplace_back(ConfigMetadata::Origin::DEFAULT, fallback);
+
+  if (from_user) {
+    result.emplace_back(ConfigMetadata::Origin::CODE, *from_user);
+  }
   if (from_env) {
-    return {ConfigMetadata::Origin::ENVIRONMENT_VARIABLE, *from_env};
-  } else if (from_user) {
-    return {ConfigMetadata::Origin::CODE, *from_user};
+    result.emplace_back(ConfigMetadata::Origin::ENVIRONMENT_VARIABLE,
+                        *from_env);
   }
-  return {ConfigMetadata::Origin::DEFAULT, fallback};
+  return result;
 }
 
 }  // namespace tracing

include/datadog/telemetry/product.h

@@ -5,6 +5,7 @@
 
 #include <string>
 #include <unordered_map>
+#include <vector>
 
 namespace datadog::telemetry {
 
@@ -30,8 +31,7 @@ struct Product final {
   /// Optional error message related to the product status.
   tracing::Optional<std::string> error_message;
   /// Map of configuration settings for the product.
-  std::unordered_map<tracing::ConfigName, tracing::ConfigMetadata>
-      configurations;
+  std::unordered_map<tracing::ConfigName, std::vector<tracing::ConfigMetadata>> configurations;
 };
 
 inline std::string_view to_string(Product::Name product) {

src/datadog/telemetry/telemetry_impl.cpp

@@ -587,11 +587,12 @@ std::string Telemetry::app_started_payload() {
 
   for (const auto& product : config_.products) {
     auto& configurations = product.configurations;
-    for (const auto& [_, config_metadata] : configurations) {
+    for (const auto& [_, config_metadatas] : configurations) {
       // if (config_metadata.value.empty()) continue;
-
-      configuration_json.emplace_back(
-          generate_configuration_field(config_metadata));
+      for (const auto& config_metadata : config_metadatas) {
+        configuration_json.emplace_back(
+            generate_configuration_field(config_metadata));
+      }
     }
 
     /// NOTE(@dmehala): Telemetry API is tightly related to APM tracing and

src/datadog/trace_sampler_config.cpp

@@ -226,7 +226,7 @@ Expected<FinalizedTraceSamplerConfig> finalize_config(
   }
 
   const auto [origin, max_per_second] =
-      pick(env_config->max_per_second, config.max_per_second, 100);
+      pick(env_config->max_per_second, config.max_per_second, 100).back();
   result.metadata[ConfigName::TRACE_SAMPLING_LIMIT] = ConfigMetadata(
       ConfigName::TRACE_SAMPLING_LIMIT, std::to_string(max_per_second), origin);
 

src/datadog/tracer_config.cpp

@@ -285,16 +285,13 @@ Expected<FinalizedTracerConfig> finalize_config(const TracerConfig &user_config,
   final_config.logger = logger;
 
   ConfigMetadata::Origin origin;
+  std::unordered_map<tracing::ConfigName, std::vector<std::pair<ConfigMetadata::Origin, std::string>>> telemetry_configs;
 
-  std::tie(origin, final_config.defaults.service) =
-      pick(env_config->service, user_config.service, "");
-
-  if (final_config.defaults.service.empty()) {
-    final_config.defaults.service = get_process_name();
-  }
-
-  final_config.metadata[ConfigName::SERVICE_NAME] = ConfigMetadata(
-      ConfigName::SERVICE_NAME, final_config.defaults.service, origin);
+  auto configs = pick(env_config->service, user_config.service, get_process_name());
+  const auto& winning_config = configs.back();
+  final_config.defaults.service = winning_config.value;
+  telemetry_configs[ConfigName::SERVICE_NAME] = configs;
+  final_config.metadata[ConfigName::SERVICE_NAME] = ConfigMetadata(ConfigName::SERVICE_NAME, winning_config.value, winning_config.origin);;
 
   final_config.defaults.service_type =
       value_or(env_config->service_type, user_config.service_type, "web");