You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: prometheus_sink.rb
    path of file: ./repos/foreman/lib/foreman/telemetry_sinks
    
    the code of the file until where you have to start completion: module Foreman
  module TelemetrySinks
    class PrometheusSink
      PROMETHEUS_STORE_DIR = File.join(Rails.root, 'tmp', 'prometheus')

     
    
      def add_counter(name, description, instance_labels)
        @prom.counter(name.to_sym, docstring: description, labels: instance_labels)
      end

      def add_gauge(name, description, instance_labels)
        @prom.gauge(name.to_sym, docstring: description, labels: instance_labels)
      end

      def add_histogram(name, description, instance_labels, buckets)
        @prom.histogram(name.to_sym, docstring: description, buckets: buckets, labels: instance_labels)
      end

      def increment_counter(name, value, tags)
        @prom.get(name.to_sym).increment(by: value, labels: tags)
      end

      def set_gauge(name, value, tags)
        @prom.get(name.to_sym).set(value, labels: tags)
      end

      def observe_histogram(name, value, tags)
        @prom.get(name.to_sym).observe(value, labels: tags)
      end
    end
  end
end