Class: Langfuse::Client

Inherits:
Object
  • Object
show all
Defined in:
lib/langfuse/client.rb

Defined Under Namespace

Classes: StdoutLogDevice

Constant Summary collapse

MAX_BATCH_SIZE_BYTES =

The ingestion API limits batch payloads to 3.5 MB in total

3_500_000
ENVIRONMENT_PATTERN =

Allowed format for the tracing environment field

/\A(?!langfuse)[a-z0-9\-_]{1,40}\z/

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(public_key: nil, secret_key: nil, host: nil, debug: false, timeout: 30, retries: 3, flush_interval: nil, auto_flush: nil, ingestion_mode: nil, environment: nil, sample_rate: nil, mask: nil, flush_at: nil, logger: nil, shutdown_on_exit: nil) ⇒ Client

Returns a new instance of Client.

Raises:



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# File 'lib/langfuse/client.rb', line 33

def initialize(public_key: nil, secret_key: nil, host: nil, debug: false, timeout: 30, retries: 3,
               flush_interval: nil, auto_flush: nil, ingestion_mode: nil, environment: nil,
               sample_rate: nil, mask: nil, flush_at: nil, logger: nil, shutdown_on_exit: nil)
  @public_key = config_value(public_key, 'LANGFUSE_PUBLIC_KEY', :public_key)
  @secret_key = config_value(secret_key, 'LANGFUSE_SECRET_KEY', :secret_key)
  @host = host || ENV['LANGFUSE_HOST'] || ENV['LANGFUSE_BASE_URL'] || Langfuse.configuration.host
  @debug = debug || ENV['LANGFUSE_DEBUG'] == 'true' || Langfuse.configuration.debug
  @timeout = config_value(timeout, nil, :timeout) { 30 }
  @retries = config_value(retries, nil, :retries) { 3 }
  @flush_interval = config_value(flush_interval, 'LANGFUSE_FLUSH_INTERVAL', :flush_interval) { 5 }
  @flush_at = config_value(flush_at, 'LANGFUSE_FLUSH_AT', :flush_at) { 15 }
  @auto_flush = resolve_auto_flush(auto_flush)
  @ingestion_mode = resolve_ingestion_mode(ingestion_mode)
  @logger = logger || Langfuse.configuration.logger || build_default_logger
  @environment = resolve_environment(environment)
  @sample_rate = resolve_sample_rate(sample_rate)
  @mask = resolve_mask(mask)
  @shutdown_on_exit = shutdown_on_exit.nil? ? Langfuse.configuration.shutdown_on_exit : shutdown_on_exit
  @shutdown = false

  raise AuthenticationError, 'Public key is required' unless @public_key
  raise AuthenticationError, 'Secret key is required' unless @secret_key

  @connection = build_connection
  @otel_connection = build_otel_connection if @ingestion_mode == :otel
  @otel_exporter = OtelExporter.new(connection: @otel_connection, debug: @debug, logger: @logger) if @ingestion_mode == :otel
  @event_queue = Concurrent::Array.new
  @flush_mutex = Mutex.new
  @flush_condition = ConditionVariable.new
  @flush_thread = start_flush_thread if @auto_flush
  register_shutdown_hook if @shutdown_on_exit
end

Instance Attribute Details

#auto_flush ⇒ Object (readonly)

Returns the value of attribute auto_flush.



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# File 'lib/langfuse/client.rb', line 30

def auto_flush
  @auto_flush
end

#debug ⇒ Object (readonly)

Returns the value of attribute debug.



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# File 'lib/langfuse/client.rb', line 30

def debug
  @debug
end

#environment ⇒ Object (readonly)

Returns the value of attribute environment.



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# File 'lib/langfuse/client.rb', line 30

def environment
  @environment
end

#flush_at ⇒ Object (readonly)

Returns the value of attribute flush_at.



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# File 'lib/langfuse/client.rb', line 30

def flush_at
  @flush_at
end

#flush_interval ⇒ Object (readonly)

Returns the value of attribute flush_interval.



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# File 'lib/langfuse/client.rb', line 30

def flush_interval
  @flush_interval
end

#host ⇒ Object (readonly)

Returns the value of attribute host.



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# File 'lib/langfuse/client.rb', line 30

def host
  @host
end

#ingestion_mode ⇒ Object (readonly)

Returns the value of attribute ingestion_mode.



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# File 'lib/langfuse/client.rb', line 30

def ingestion_mode
  @ingestion_mode
end

#logger ⇒ Object (readonly)

Returns the value of attribute logger.



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# File 'lib/langfuse/client.rb', line 30

def logger
  @logger
end

#mask ⇒ Object (readonly)

Returns the value of attribute mask.



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# File 'lib/langfuse/client.rb', line 30

def mask
  @mask
end

#public_key ⇒ Object (readonly)

Returns the value of attribute public_key.



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# File 'lib/langfuse/client.rb', line 30

def public_key
  @public_key
end

#retries ⇒ Object (readonly)

Returns the value of attribute retries.



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# File 'lib/langfuse/client.rb', line 30

def retries
  @retries
end

#sample_rate ⇒ Object (readonly)

Returns the value of attribute sample_rate.



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# File 'lib/langfuse/client.rb', line 30

def sample_rate
  @sample_rate
end

#secret_key ⇒ Object (readonly)

Returns the value of attribute secret_key.



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# File 'lib/langfuse/client.rb', line 30

def secret_key
  @secret_key
end

#timeout ⇒ Object (readonly)

Returns the value of attribute timeout.



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# File 'lib/langfuse/client.rb', line 30

def timeout
  @timeout
end

Instance Method Details

#agent(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create an agent observation (wrapper around span with as_type: 'agent')



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# File 'lib/langfuse/client.rb', line 124

def agent(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
          metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
          version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::AGENT,
    **kwargs
  )
end

#chain(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create a chain observation (wrapper around span with as_type: 'chain')



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# File 'lib/langfuse/client.rb', line 166

def chain(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
          metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
          version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::CHAIN,
    **kwargs
  )
end

#create_prompt(name:, prompt:, labels: [], config: {}, **kwargs) ⇒ Object 



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# File 'lib/langfuse/client.rb', line 363

def create_prompt(name:, prompt:, labels: [], config: {}, **kwargs)
  data = {
    name: name,
    prompt: prompt,
    labels: labels,
    config: config,
    **kwargs
  }

  response = post('/api/public/v2/prompts', data)
  Prompt.new(response.body)
end

#embedding(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, model: nil, usage: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create an embedding observation (wrapper around span with as_type: 'embedding')



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# File 'lib/langfuse/client.rb', line 208

def embedding(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
              model: nil, usage: nil, metadata: nil, level: nil, status_message: nil,
              parent_observation_id: nil, version: nil, **kwargs)
  merged_metadata = (metadata || {}).merge(
    { model: model, usage: usage }.compact
  )
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: merged_metadata.empty? ? nil : merged_metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::EMBEDDING,
    **kwargs
  )
end

#enqueue_event(type, body) ⇒ Object

Event queue management



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# File 'lib/langfuse/client.rb', line 408

def enqueue_event(type, body)
  # 验证事件类型是否有效
  valid_types = %w[
    trace-create trace-update
    generation-create generation-update
    span-create span-update
    event-create
    score-create
  ]

  unless valid_types.include?(type)
    @logger.debug("Warning: Invalid event type '#{type}'. Skipping event.")
    return
  end

  prepared_body = Utils.prepare_event_body(body)
  inject_default_environment(prepared_body)
  apply_mask(prepared_body)

  return unless sampled_event?(type, prepared_body)

  event = {
    id: Utils.generate_id,
    type: type,
    timestamp: Utils.current_timestamp,
    body: prepared_body
  }

  if type == 'trace-update'
    # 查找对应的 trace-create 事件并更新
    trace_id = body['id'] || body[:id]
    if trace_id
      existing_event_index = @event_queue.find_index do |existing_event|
        existing_event[:type] == 'trace-create' &&
          (existing_event[:body]['id'] == trace_id || existing_event[:body][:id] == trace_id)
      end

      if existing_event_index
        # 更新现有的 trace-create 事件
        @event_queue[existing_event_index][:body].merge!(event[:body])
        @event_queue[existing_event_index][:timestamp] = event[:timestamp]
        @logger.debug("Updated existing trace-create event for trace_id: #{trace_id}")
      else
        # 如果没找到对应的 trace-create 事件，将 trace-update 转换为 trace-create
        event[:type] = 'trace-create'
        @event_queue << event
        @logger.debug("Converted trace-update to trace-create for trace_id: #{trace_id}")
      end
    else
      @logger.debug('Warning: trace-update event missing trace_id, skipping')
    end
  else
    @event_queue << event
  end
  @logger.debug("Enqueued event: #{type}")

  request_flush if @auto_flush && @event_queue.length >= @flush_at
end

#evaluator_obs(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create an evaluator observation (wrapper around span with as_type: 'evaluator')



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# File 'lib/langfuse/client.rb', line 232

def evaluator_obs(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
                  metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
                  version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::EVALUATOR,
    **kwargs
  )
end

#event(trace_id:, name:, id: nil, start_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Event operations



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# File 'lib/langfuse/client.rb', line 305

def event(trace_id:, name:, id: nil, start_time: nil, input: nil, output: nil, metadata: nil,
          level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs)
  Event.new(
    client: self,
    trace_id: trace_id,
    id: id || generate_observation_id,
    name: name,
    start_time: start_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    **kwargs
  )
end

#flush ⇒ Object 



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# File 'lib/langfuse/client.rb', line 467

def flush
  return if @event_queue.empty?

  events = @event_queue.shift(@event_queue.length)
  return if events.empty?

  send_batch(events)
end

#generate_observation_id ⇒ Object

Generate an observation ID matching the active ingestion mode (W3C 16-char hex for :otel, UUID for :legacy)



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# File 'lib/langfuse/client.rb', line 74

def generate_observation_id
  @ingestion_mode == :otel ? Utils.generate_hex_span_id : Utils.generate_id
end

#generate_trace_id ⇒ Object

Generate a trace ID matching the active ingestion mode (W3C 32-char hex for :otel, UUID for :legacy)



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# File 'lib/langfuse/client.rb', line 68

def generate_trace_id
  @ingestion_mode == :otel ? Utils.generate_hex_trace_id : Utils.generate_id
end

#generation(trace_id:, id: nil, name: nil, start_time: nil, end_time: nil, completion_start_time: nil, model: nil, model_parameters: nil, input: nil, output: nil, usage: nil, usage_details: nil, cost_details: nil, prompt: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Generation operations



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# File 'lib/langfuse/client.rb', line 274

def generation(trace_id:, id: nil, name: nil, start_time: nil, end_time: nil, completion_start_time: nil,
               model: nil, model_parameters: nil, input: nil, output: nil, usage: nil,
               usage_details: nil, cost_details: nil, prompt: nil,
               metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
               version: nil, **kwargs)
  Generation.new(
    client: self,
    trace_id: trace_id,
    id: id || generate_observation_id,
    name: name,
    start_time: start_time || Utils.current_timestamp,
    end_time: end_time,
    completion_start_time: completion_start_time,
    model: model,
    model_parameters: model_parameters,
    input: input,
    output: output,
    usage: usage,
    usage_details: usage_details,
    cost_details: cost_details,
    prompt: prompt,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    **kwargs
  )
end

#get_prompt(name, version: nil, label: nil, cache_ttl_seconds: 60) ⇒ Object

Prompt operations



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# File 'lib/langfuse/client.rb', line 325

def get_prompt(name, version: nil, label: nil, cache_ttl_seconds: 60)
  cache_key = "prompt:#{name}:#{version}:#{label}"

  if (cached_prompt = @prompt_cache&.dig(cache_key)) && (Time.now - cached_prompt[:cached_at] < cache_ttl_seconds)
    return cached_prompt[:prompt]
  end

  encoded_name = Utils.url_encode(name)
  path = "/api/public/v2/prompts/#{encoded_name}"
  params = {}
  params[:version] = version if version
  params[:label] = label if label

  @logger.debug("Making request to: #{@host}#{path} with params: #{params}")

  response = get(path, params)

  @logger.debug("Response status: #{response.status}")
  @logger.debug("Response headers: #{response.headers}")
  @logger.debug("Response body type: #{response.body.class}")

  # Check if response body is a string (HTML) instead of parsed JSON
  if response.body.is_a?(String) && response.body.include?('<!DOCTYPE html>')
    @logger.debug('Received HTML response instead of JSON:')
    @logger.debug(response.body[0..200])
    raise APIError,
          'Received HTML response instead of JSON. This usually indicates a 404 error or incorrect API endpoint.'
  end

  prompt = Prompt.new(response.body)

  # Cache the prompt
  @prompt_cache ||= {}
  @prompt_cache[cache_key] = { prompt: prompt, cached_at: Time.now }

  prompt
end

#guardrail(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create a guardrail observation (wrapper around span with as_type: 'guardrail')



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# File 'lib/langfuse/client.rb', line 253

def guardrail(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
              metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
              version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::GUARDRAIL,
    **kwargs
  )
end

#retriever(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create a retriever observation (wrapper around span with as_type: 'retriever')



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# File 'lib/langfuse/client.rb', line 187

def retriever(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
              metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
              version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::RETRIEVER,
    **kwargs
  )
end

#score(name:, value:, trace_id: nil, observation_id: nil, session_id: nil, dataset_run_id: nil, id: nil, data_type: nil, comment: nil, metadata: nil, config_id: nil, queue_id: nil, environment: nil, **kwargs) ⇒ Object Also known as: create_score

Score/Evaluation operations Scores can target a trace, an observation (trace_id + observation_id), a session (session_id) or a dataset run (dataset_run_id).



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# File 'lib/langfuse/client.rb', line 379

def score(name:, value:, trace_id: nil, observation_id: nil, session_id: nil, dataset_run_id: nil,
          id: nil, data_type: nil, comment: nil, metadata: nil, config_id: nil, queue_id: nil,
          environment: nil, **kwargs)
  data = {
    id: id,
    trace_id: trace_id,
    observation_id: observation_id,
    session_id: session_id,
    dataset_run_id: dataset_run_id,
    name: name,
    value: value,
    data_type: data_type,
    comment: comment,
    metadata: metadata,
    config_id: config_id,
    queue_id: queue_id,
    environment: environment,
    **kwargs
  }.compact

  if trace_id.nil? && observation_id.nil? && session_id.nil? && dataset_run_id.nil?
    @logger.warn('Langfuse score should reference a trace_id, observation_id, session_id or dataset_run_id')
  end

  enqueue_event('score-create', data)
end

#shutdown ⇒ Object 



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# File 'lib/langfuse/client.rb', line 476

def shutdown
  return if @shutdown

  @shutdown = true
  @flush_thread&.kill if @auto_flush
  flush unless @event_queue.empty?
end

#span(trace_id:, id: nil, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, as_type: nil, **kwargs) ⇒ Object

Span operations



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# File 'lib/langfuse/client.rb', line 99

def span(trace_id:, id: nil, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
         metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
         version: nil, as_type: nil, **kwargs)
  Span.new(
    client: self,
    trace_id: trace_id,
    id: id || generate_observation_id,
    name: name,
    start_time: start_time || Utils.current_timestamp,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: as_type,
    **kwargs
  )
end

#tool(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil, metadata: nil, level: nil, status_message: nil, parent_observation_id: nil, version: nil, **kwargs) ⇒ Object

Create a tool observation (wrapper around span with as_type: 'tool')



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# File 'lib/langfuse/client.rb', line 145

def tool(trace_id:, name: nil, start_time: nil, end_time: nil, input: nil, output: nil,
         metadata: nil, level: nil, status_message: nil, parent_observation_id: nil,
         version: nil, **kwargs)
  span(
    trace_id: trace_id,
    name: name,
    start_time: start_time,
    end_time: end_time,
    input: input,
    output: output,
    metadata: metadata,
    level: level,
    status_message: status_message,
    parent_observation_id: parent_observation_id,
    version: version,
    as_type: ObservationType::TOOL,
    **kwargs
  )
end

#trace(id: nil, name: nil, user_id: nil, session_id: nil, version: nil, release: nil, input: nil, output: nil, metadata: nil, tags: nil, timestamp: nil, **kwargs) ⇒ Object

Trace operations



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# File 'lib/langfuse/client.rb', line 79

def trace(id: nil, name: nil, user_id: nil, session_id: nil, version: nil, release: nil,
          input: nil, output: nil, metadata: nil, tags: nil, timestamp: nil, **kwargs)
  Trace.new(
    client: self,
    id: id || generate_trace_id,
    name: name,
    user_id: user_id,
    session_id: session_id,
    version: version,
    release: release,
    input: input,
    output: output,
    metadata: metadata,
    tags: tags,
    timestamp: timestamp || Utils.current_timestamp,
    **kwargs
  )
end