producer_component.hpp

#pragma once
 
#include <string_view>
 
#include <userver/kafka/producer.hpp>
 
#include <userver/components/component_base.hpp>
#include <userver/utils/statistics/entry.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace kafka {
 
// clang-format off
 
/// @ingroup userver_components
///
/// @brief Apache Kafka Producer client component.
///
/// ## Static configuration example:
///
/// @snippet kafka/functional_tests/integrational_tests/static_config.yaml  Kafka service sample - producer static config
///
/// ## Secdist format
///
/// A Kafka alias in secdist is described as a JSON object
/// `kafka_settings`, containing credentials of Kafka brokers.
///
/// @snippet kafka/functional_tests/integrational_tests/tests/conftest.py  Kafka service sample - secdist
///
/// ## Static options:
/// Name                     | Description                                      | Default value
/// ------------------------ | ------------------------------------------------ | ---------------
/// delivery_timeout         | time a produced message waits for successful delivery | --
/// queue_buffering_max      | delay to wait for messages to be transmitted to broker | --
/// enable_idempotence       | whether to make producer idempotent | false
/// poll_timeout             | time producer waits for new delivery events | 10ms
/// send_retries_count       | how many times producer retries transient delivery errors | 5
/// security_protocol        | protocol used to communicate with brokers | --
/// sasl_mechanisms          | SASL mechanism to use for authentication | none
/// ssl_ca_location          | file or directory path to CA certificate(s) for verifying the broker's key | none
/// rd_kafka_custom_options  | a map of librdkafka library additional options | '{}'
 
// clang-format on
 
class ProducerComponent final : public components::ComponentBase {
 public:
  static constexpr std::string_view kName = "kafka-producer";
 
  ProducerComponent(const components::ComponentConfig& config,
                    const components::ComponentContext& context);
  ~ProducerComponent() override;
 
  Producer& GetProducer();
 
  static yaml_config::Schema GetStaticConfigSchema();
 
 private:
  Producer producer_;
 
  /// @note Subscriptions must be the last fields! Add new fields above this
  /// comment.
  utils::statistics::Entry statistics_holder_;
};
 
}  // namespace kafka
 
USERVER_NAMESPACE_END