base.rb

# coding: utf-8

module Stoplight
  module DataStore
    class Base
      # @return [Array<String>]
      def names
        fail NotImplementedError
      end

      # Deletes all green lights without failures.
      def purge
        fail NotImplementedError
      end

      # @param _name [String]
      def delete(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [String]
      def color(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @param _error [Exception]
      def record_failure(_name, _error)
        fail NotImplementedError
      end

      # @param _name [String]
      def clear_failures(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [Array<Failure>]
      def failures(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [Integer]
      def threshold(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @param _threshold [Integer]
      # @return (see #threshold)
      def set_threshold(_name, _threshold)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return (see #attempts)
      def record_attempt(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      def clear_attempts(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [Integer]
      def attempts(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [String]
      def state(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @param _state [String]
      # @return [String]
      def set_state(_name, _state)
        # REVIEW: Should we clear failures here?
        fail NotImplementedError
      end

      # @param _name [String]
      # @return [Integer]
      def timeout(_name)
        fail NotImplementedError
      end

      # @param _name [String]
      # @param _timeout [Integer]
      # @return [Integer]
      def set_timeout(_name, _timeout)
        fail NotImplementedError
      end

      private

      # rubocop:disable Metrics/CyclomaticComplexity
      # rubocop:disable Metrics/PerceivedComplexity
      def _color(failures, state, threshold, timeout)
        return COLOR_GREEN if state == STATE_LOCKED_GREEN
        return COLOR_RED if state == STATE_LOCKED_RED

        threshold = threshold ? threshold.to_i : DEFAULT_THRESHOLD
        return COLOR_GREEN if failures.size < threshold

        # If the threshold is 0, the light is always red.
        return COLOR_RED if failures.empty?

        timeout = timeout ? timeout.to_i : DEFAULT_TIMEOUT
        return COLOR_YELLOW if Time.now - failures.last.time > timeout

        COLOR_RED
      end
      # rubocop:enable Metrics/CyclomaticComplexity
      # rubocop:enable Metrics/PerceivedComplexity

      def validate_state!(state)
        return if DataStore::STATES.include?(state)
        fail ArgumentError, 'Invalid state'
      end

      def attempts_key
        key('attempts')
      end

      def failures_key(name)
        key('failures', name)
      end

      def states_key
        key('states')
      end

      def thresholds_key
        key('thresholds')
      end

      def timeouts_key
        key('timeouts')
      end

      def key(slug, name = nil)
        [KEY_PREFIX, name, slug].compact.join(':')
      end
    end
  end
end