Module: Deimos

Includes:
Instrumentation, FigTree
Defined in:
lib/deimos.rb,
lib/deimos/logging.rb,
lib/deimos/message.rb,
lib/deimos/version.rb,
lib/deimos/consumer.rb,
lib/deimos/producer.rb,
lib/deimos/poll_info.rb,
lib/deimos/exceptions.rb,
lib/deimos/transcoder.rb,
lib/deimos/kafka_source.rb,
lib/deimos/metrics/mock.rb,
lib/deimos/test_helpers.rb,
lib/deimos/tracing/mock.rb,
lib/deimos/backends/base.rb,
lib/deimos/backends/test.rb,
lib/deimos/kafka_message.rb,
lib/deimos/shared_config.rb,
lib/deimos/backends/kafka.rb,
lib/deimos/backends/outbox.rb,
lib/deimos/metrics/datadog.rb,
lib/deimos/tracing/datadog.rb,
lib/deimos/utils/db_poller.rb,
lib/deimos/ext/schema_route.rb,
lib/deimos/kafka_topic_info.rb,
lib/deimos/metrics/provider.rb,
lib/deimos/tracing/provider.rb,
lib/deimos/schema_class/base.rb,
lib/deimos/schema_class/enum.rb,
lib/deimos/ext/consumer_route.rb,
lib/deimos/ext/producer_route.rb,
lib/deimos/utils/schema_class.rb,
lib/deimos/schema_class/record.rb,
lib/deimos/backends/kafka_async.rb,
lib/deimos/config/configuration.rb,
lib/deimos/schema_backends/base.rb,
lib/deimos/schema_backends/mock.rb,
lib/deimos/utils/db_poller/base.rb,
lib/deimos/utils/deadlock_retry.rb,
lib/deimos/schema_backends/plain.rb,
lib/deimos/utils/outbox_producer.rb,
lib/deimos/active_record_consumer.rb,
lib/deimos/active_record_producer.rb,
lib/deimos/ext/producer_middleware.rb,
lib/deimos/metrics/minimal_datadog.rb,
lib/generators/deimos/v2_generator.rb,
lib/deimos/consume/batch_consumption.rb,
lib/deimos/schema_backends/avro_base.rb,
lib/deimos/schema_backends/avro_local.rb,
lib/deimos/schema_backends/proto_base.rb,
lib/deimos/utils/db_poller/time_based.rb,
lib/deimos/consume/message_consumption.rb,
lib/deimos/schema_backends/proto_local.rb,
lib/deimos/utils/db_poller/state_based.rb,
lib/deimos/ext/producer_metrics_listener.rb,
lib/generators/deimos/db_poller_generator.rb,
lib/deimos/schema_backends/avro_validation.rb,
lib/deimos/metrics/minimal_datadog_listener.rb,
lib/generators/deimos/schema_class_generator.rb,
lib/deimos/active_record_consume/batch_record.rb,
lib/deimos/active_record_consume/batch_slicer.rb,
lib/deimos/active_record_consume/mass_updater.rb,
lib/generators/deimos/active_record_generator.rb,
lib/deimos/schema_backends/avro_schema_coercer.rb,
lib/generators/deimos/bulk_import_id_generator.rb,
lib/generators/deimos/outbox_backend_generator.rb,
lib/deimos/schema_backends/avro_schema_registry.rb,
lib/deimos/schema_backends/proto_schema_registry.rb,
lib/deimos/active_record_consume/batch_consumption.rb,
lib/deimos/active_record_consume/batch_record_list.rb,
lib/deimos/active_record_consume/message_consumption.rb,
lib/deimos/active_record_consume/schema_model_converter.rb,
sig/defs.rbs

Overview

Generates a new consumer.

Defined Under Namespace

Modules: ActiveRecordConsume, Backends, Consume, Generators, Instrumentation, KafkaListener, KafkaSource, Logging, Metrics, PhobosConfig, ProducerMiddleware, SchemaBackends, SchemaClass, SharedConfig, TestHelpers, Tracing, Utils Classes: ActiveRecordConsumer, ActiveRecordProducer, AvroSchemaCoercer, BatchConsumer, BatchFallbackError, Consumer, ConsumerRoute, KafkaMessage, KafkaTopicInfo, Message, MissingImplementationError, PollInfo, Producer, ProducerMetricsListener, ProducerRoute, Railtie, RegistryInfo, SchemaField, SchemaRoute, Transcoder

Constant Summary collapse

EVENT_TYPES = 
%w(
  deimos.ar_consumer.consume_batch
  deimos.encode_message
  deimos.batch_consumption.invalid_records
  deimos.batch_consumption.valid_records
  deimos.batch_consumption.initial_failure
  deimos.outbox.produce
).freeze
VERSION =

Returns:

  • (Object) 
'2.6.0'

Class Attribute Summary collapse

Class Method Summary collapse

Class Attribute Details

.mock_backends ⇒ Boolean

Returns for use in unit tests.

Returns:

  • (Boolean) —

    for use in unit tests



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# File 'lib/deimos.rb', line 59

def mock_backends
  @mock_backends
end

Class Method Details

.decode(schema:, namespace:, payload:) ⇒ ::Hash[untyped, untyped]?

@param schema

@param namespace

@param payload

Parameters:

  • schema: (String)
  • namespace: (String)
  • payload: (String)

Returns:

  • (::Hash[untyped, untyped], nil) 


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# File 'lib/deimos.rb', line 141

def decode(schema:, namespace:, payload:)
  self.schema_backend(schema: schema, namespace: namespace).decode(payload)
end

.decode_message(message) ⇒ Object

Parameters:

  • message (Hash) —

    a Karafka message with keys :payload, :key and :topic



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# File 'lib/deimos.rb', line 146

def decode_message(message)
  topic = message[:topic]
  if Deimos.config.producers.topic_prefix
    topic = topic.sub(Deimos.config.producers.topic_prefix, '')
  end
  config = karafka_config_for(topic: topic)
  return message unless config

  message[:payload] = config.deserializers[:payload].decode_message_hash(message[:payload])
  if message[:key] && config.deserializers[:key].respond_to?(:decode_message_hash)
    message[:key] = config.deserializers[:key].decode_message_hash(message[:key])
  end
end

.disable_producers(*producer_classes, &block) ⇒ void

This method returns an undefined value.

Run a block without allowing any messages to be produced to Kafka. Optionally add a list of producer classes to limit the disabling to those classes.

@param producer_classes

Parameters:

  • producer_classes (::Array[Class], Class) 


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# File 'lib/deimos/producer.rb', line 16

def disable_producers(*producer_classes, &block)
  if producer_classes.any?
    _disable_producer_classes(producer_classes, &block)
    return
  end

  if Thread.current[:frk_disable_all_producers] # nested disable block
    yield
    return
  end

  begin
    Thread.current[:frk_disable_all_producers] = true
    yield
  ensure
    Thread.current[:frk_disable_all_producers] = false
  end
end

.encode(schema:, namespace:, payload:, subject: nil) ⇒ Object

@param schema

@param namespace

@param payload

@param subject



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# File 'lib/deimos.rb', line 132

def encode(schema:, namespace:, payload:, subject: nil)
  self.schema_backend(schema: schema, namespace: namespace).
    encode(payload, topic: subject || "#{namespace}.#{schema}" )
end

.generate_key_schemas ⇒ Object 



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# File 'lib/deimos/config/configuration.rb', line 27

def generate_key_schemas
  Deimos.karafka_configs.each do |config|
    transcoder = config.deserializers[:key]

    next unless transcoder.respond_to?(:key_field) &&
                transcoder.key_field &&
                transcoder.backend.supports_key_schemas?

    transcoder.backend = Deimos.schema_backend(schema: config.schema,
                                               namespace: config.namespace,
                                               backend: transcoder.backend_type)
    transcoder.backend.generate_key_schema(transcoder.key_field)
  end
end

.karafka_config_for(topic: nil, producer: nil) ⇒ Karafka::Routing::Topic?

Parameters:

  • topic (String) (defaults to: nil)

Returns:

  • (Karafka::Routing::Topic, nil) 


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# File 'lib/deimos.rb', line 230

def karafka_config_for(topic: nil, producer: nil)
  if topic
    karafka_configs.find { |t| t.name == topic }
  elsif producer
    karafka_configs.find { |t| t.producer_classes&.include?(producer) }
  end
end

.karafka_configs ⇒ Array<Karafka::Routing::Topic]

Returns Array<Karafka::Routing::Topic].

Returns:

  • (Array<Karafka::Routing::Topic]) —

    Array<Karafka::Routing::Topic]



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# File 'lib/deimos.rb', line 224

def karafka_configs
  Karafka::App.routes.flat_map(&:topics).flat_map(&:to_a)
end

.load_generated_schema_classes ⇒ void

This method returns an undefined value.

Loads generated classes



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# File 'lib/deimos/config/configuration.rb', line 44

def load_generated_schema_classes
  if Deimos.config.schema.generated_class_path.nil?
    raise 'Cannot use schema classes without schema.generated_class_path. ' \
          'Please provide a directory.'
  end

  Dir["./#{Deimos.config.schema.generated_class_path}/**/*.rb"].
    each { |f| require f }
rescue LoadError
  raise 'Cannot load schema classes. Please regenerate classes with' \
        'rake deimos:generate_schema_models.'
end

.producer_for(topic) ⇒ Object

Parameters:

  • topic (String) 


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# File 'lib/deimos.rb', line 244

def producer_for(topic)
  @producers[topic] || Karafka.producer
end

.producers_disabled?(producer_class = nil) ⇒ Boolean

Are producers disabled? If a class is passed in, check only that class. Otherwise check if the global disable flag is set.

@param producer_class

Parameters:

  • producer_class (Class, nil) (defaults to: nil)

Returns:

  • (Boolean) 


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# File 'lib/deimos/producer.rb', line 52

def producers_disabled?(producer_class=nil)
  return true if Deimos.config.producers.disabled

  Thread.current[:frk_disable_all_producers] ||
    Thread.current[:frk_disabled_producers]&.include?(producer_class)
end

.schema_backend(schema:, namespace:, registry_info: nil, backend: Deimos.config.schema.backend) ⇒ Deimos::SchemaBackends::Base

@param schema

@param namespace

Parameters:

  • schema: (String, Symbol)
  • namespace: (String)

Returns:



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# File 'lib/deimos.rb', line 99

def schema_backend(schema:, namespace:,
                   registry_info: nil,
                   backend: Deimos.config.schema.backend)
  if config.schema.use_schema_classes
    # Initialize an instance of the provided schema
    # in the event the schema class is an override, the inherited
    # schema and namespace will be applied
    schema_class = Utils::SchemaClass.klass(schema, namespace)
    if schema_class.nil?
      schema_backend_class(backend: backend).
        new(
          schema: schema,
          namespace: namespace,
          registry_info: registry_info
        )
    else
      schema_instance = schema_class.allocate
      schema_backend_class(backend: backend).
        new(schema: schema_instance.schema,
            namespace: schema_instance.namespace,
            registry_info: registry_info)
    end
  else
    schema_backend_class(backend: backend).
      new(schema: schema, namespace: namespace, registry_info: registry_info)
  end
end

.schema_backend_class(backend: nil) ⇒ Class<Deimos::SchemaBackends::Base>

Parameters:

  • backend (Symbol, nil) (defaults to: nil)

Returns:



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# File 'lib/deimos.rb', line 63

def schema_backend_class(backend: nil)
  backend ||= Deimos.config.schema.backend

  require "deimos/schema_backends/#{backend}"

  klass = "Deimos::SchemaBackends::#{backend.to_s.classify}".constantize
  if self.mock_backends
    require "deimos/schema_backends/#{klass.mock_backend}"
    klass = "Deimos::SchemaBackends::#{klass.mock_backend.to_s.classify}".constantize
  end
  klass
end

.schema_backend_for(topic_name) ⇒ SchemaBackends::Base

Parameters:

  • topic_name (String)

Returns:



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# File 'lib/deimos.rb', line 78

def schema_backend_for(topic_name)
  config = Deimos.karafka_config_for(topic: topic_name)
  registry_info = if config.registry_url
                    Deimos::RegistryInfo.new(
                      config.registry_url,
                      config.registry_user,
                      config.registry_password
                    )
                  else
                    nil
                  end
  self.schema_backend(schema: config.schema,
                      namespace: config.namespace,
                      registry_info: registry_info,
                      backend: config.schema_backend || Deimos.config.schema.backend)
end

.setup_karafka ⇒ Object 



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# File 'lib/deimos.rb', line 201

def setup_karafka
  setup_producers
  waterdrop_producers.each do |producer|
    producer.middleware.append(Deimos::ProducerMiddleware)
    producer.monitor.subscribe(ProducerMetricsListener.new)
    producer.monitor.subscribe('error.occurred') do |event|
      if event.payload.key?(:messages)
        topic = event[:messages].first[:topic]
        config = Deimos.karafka_config_for(topic: topic)
        message = Deimos::Logging.messages_log_text(config&.payload_log, event[:messages])
        json = begin
                 message.to_json
        rescue StandardError
                 message.to_s
        end
        Karafka.logger.error("Error producing messages: #{event[:error].message} #{json}")
      end
    end
  end
  EVENT_TYPES.each { |type| Karafka.monitor.notifications_bus.register_event(type) }
end

.setup_producers ⇒ Object 



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# File 'lib/deimos.rb', line 184

def setup_producers
  @producers = {}
  producers_by_broker = {}
  Deimos.karafka_configs.each do |topic|
    broker = topic.kafka[:'bootstrap.servers']
    producers_by_broker[broker] ||= ::WaterDrop::Producer.new do |p_config|
      config_hash = Karafka::Setup::Config.config.kafka.merge(topic.kafka)
      p_config.kafka = Karafka::Setup::AttributesMap.producer(config_hash)
    end
    @producers[topic.name] = producers_by_broker[broker]
  end
  # Karafka.producer's kafka config is captured at first Karafka::App.setup;
  # apply the merged global so later overrides actually take effect.
  Karafka.producer.config.kafka =
    Karafka::Setup::AttributesMap.producer(Karafka::Setup::Config.config.kafka.dup)
end

.start_db_backend! ⇒ void

This method returns an undefined value.

Start the DB producers to send Kafka messages.

@param thread_count — the number of threads to start.

Parameters:

  • thread_count: (Integer) 


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# File 'sig/defs.rbs', line 38

def self.start_db_backend!: (?thread_count: Integer) -> void

.start_outbox_backend!(thread_count: 1) ⇒ void

This method returns an undefined value.

Start the DB producers to send Kafka messages.

Parameters:

  • thread_count (Integer) (defaults to: 1) —

    the number of threads to start.



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# File 'lib/deimos.rb', line 163

def start_outbox_backend!(thread_count: 1)
  Sigurd.exit_on_signal = true
  if self.config.producers.backend != :outbox
    raise('Publish backend is not set to :outbox, exiting')
  end

  if thread_count.nil? || thread_count.zero?
    raise('Thread count is not given or set to zero, exiting')
  end

  producers = (1..thread_count).map do
    Deimos::Utils::OutboxProducer.
      new(self.config.outbox.logger || Karafka.logger)
  end
  executor = Sigurd::Executor.new(producers,
                                  sleep_seconds: 5,
                                  logger: Karafka.logger)
  signal_handler = Sigurd::SignalHandler.new(executor)
  signal_handler.run!
end

.topic_for_consumer(handler_class) ⇒ String?

Returns:

  • (String, nil) 


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# File 'lib/deimos.rb', line 249

def topic_for_consumer(handler_class)
  Deimos.karafka_configs.each do |topic|
    if topic.consumer == handler_class
      return topic.name
    end
  end
  nil
end

.waterdrop_producers ⇒ Array<::WaterDrop::Producer>

Returns:

  • (Array<::WaterDrop::Producer>) 


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# File 'lib/deimos.rb', line 239

def waterdrop_producers
  (@producers.values + [Karafka.producer]).uniq
end