OfTheDelmer/policy_calling.md

## policy_calling.md

      
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              policy_calling.md
            
          
    A PolicyResult class to help collect the status and message from a policy check
class PolicyResult

  attr_reader :message, :status

  def initialize(params)
    @status = params.fetch(:status, false)
    @message = params.fetch(:message, :no_message)
  end

end
Then a refactor of a policy to return the status and optionally call a block with the full result
Usage:
class User < ActiveRecord::Base
...
  def verifiable?(&block)
    VerificationEligibilityPolicy.call &block
  end
  
end

current_user.verifiable? #=> true/false

current_user.verifiable? do |result|
  return nil if result.status
  redirect_to root_path, error: result.message
end

Which would have a refactor like the following:
class VerificationEligibilityPolicy

  MAX_ATTEMPTS = 2

  def self.call(params, &block)
    policy = new(params)
    result = policy.eligible?
    block.call result if block
    result.status
  end

  def initialize(params)
    @user = params.fetch(:user)
    @attempts = @user.attempts.recent
  end

  ##
  # checks that a user has not reached
  # max verification attempts or
  # that the user has waited past
  # the retry time window: 1.day
  def eligible?
    if !@user.identified_person?
      PolicyResult.new({message: "Create Identity"})
    elsif @attempts.count < MAX_ATTEMPTS
      next_time = @attempts.last.created_at + wait_time
      PolicyResult.new({message: "Please wait #{next_time}"})
    else
      PolicyResult.new({staus: true})
    end
  end

  private

  def wait_time
    1.day
  end
end