Module: ActionPolicy::Policy::Reasons

Included in:
Base
Defined in:
lib/action_policy/policy/reasons.rb

Overview

Provides failure reasons tracking functionality. That allows you to distinguish between the reasons why authorization was rejected.

It’s helpful when you compose policies (i.e. use one policy within another).

For example:

class ApplicantPolicy < ApplicationPolicy
  def show?
    user.has_permission?(:view_applicants) &&
      allowed_to?(:show?, object.stage)
  end
end

Now when you receive an exception, you have a reasons object, which contains additional information about the failure:

rescue_from ActionPolicy::Unauthorized do |ex|
  ex.reasons.messages  #=> { stage: [:show] }
end

You can also wrap local rules into ‘allowed_to?` to populate reasons:

class ApplicantPolicy < ApplicationPolicy
  def show?
    allowed_to?(:view_applicants?) &&
      allowed_to?(:show?, object.stage)
  end

  def view_applicants?
    user.has_permission?(:view_applicants)
  end
end

Defined Under Namespace

Modules: InstanceMethods

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#reasons ⇒ Object (readonly)

Returns the value of attribute reasons.



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# File 'lib/action_policy/policy/reasons.rb', line 72

def reasons
  @reasons
end

Class Method Details

.prepended(base) ⇒ Object Also known as: included 



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# File 'lib/action_policy/policy/reasons.rb', line 65

def prepended(base)
  base.prepend InstanceMethods
end

Instance Method Details

#with_clean_reasons ⇒ Object

:nodoc:



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# File 'lib/action_policy/policy/reasons.rb', line 74

def with_clean_reasons # :nodoc:
  old_reasons = reasons
  @reasons = nil
  res = yield
  @reasons = old_reasons
  res
end