hometown/lib/mastodon/middleware/prometheus_queue_time.rb

# frozen_string_literal: true

module Mastodon
  module Middleware
    class PrometheusQueueTime < ::PrometheusExporter::Middleware
      # Overwrite to only collect the queue time metric
      def call(env)
        queue_time = measure_queue_time(env)

        result = @app.call(env)

        result
      ensure
        obj = {
          type: 'web',
          queue_time: queue_time,
          default_labels: {},
        }

        @client.send_json(obj)
      end
    end
  end
end