Module: ActiveResource::Validations

Defined in:
lib/active_resource/validations.rb

Overview

Module to allow validation of Active Resource objects, which creates an Errors instance for every resource. Methods are implemented by overriding Base#validate or its variants Each of these methods can inspect the state of the object, which usually means ensuring that a number of attributes have a certain value (such as not empty, within a given range, matching a certain regular expression and so on).

Example

class Person < ActiveResource::Base
   self.site = "http://www.localhost.com:3000/"
   protected
     def validate
       errors.add_on_empty %w( first_name last_name )
       errors.add("phone_number", "has invalid format") unless phone_number =~ /[0-9]*/
     end

     def validate_on_create # is only run the first time a new object is saved
       unless valid_member?(self)
         errors.add("membership_discount", "has expired")
       end
     end

     def validate_on_update
       errors.add_to_base("No changes have occurred") if unchanged_attributes?
     end
end

person = Person.new("first_name" => "Jim", "phone_number" => "I will not tell you.")
person.save                         # => false (and doesn't do the save)
person.errors.empty?                # => false
person.errors.count                 # => 2
person.errors.on "last_name"        # => "can't be empty"
person.attributes = { "last_name" => "Halpert", "phone_number" => "555-5555" }
person.save                         # => true (and person is now saved to the remote service)

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(base) ⇒ Object

:nodoc:



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# File 'lib/active_resource/validations.rb', line 254

def self.included(base) # :nodoc:
  base.class_eval do
    alias_method_chain :save, :validation
  end
end

Instance Method Details

#errors ⇒ Object

Returns the Errors object that holds all information about attribute error messages.



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# File 'lib/active_resource/validations.rb', line 284

def errors
  @errors ||= Errors.new(self)
end

#save_with_validation ⇒ Object

Validate a resource and save (POST) it to the remote web service.



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# File 'lib/active_resource/validations.rb', line 261

def save_with_validation
  save_without_validation
  true
rescue ResourceInvalid => error
  errors.from_xml(error.response.body)
  false
end

#valid? ⇒ Boolean

Checks for errors on an object (i.e., is resource.errors empty?).

Examples

my_person = Person.create(params[:person])
my_person.valid?
# => true

my_person.errors.add('login', 'can not be empty') if my_person. == ''
my_person.valid?
# => false

Returns:

  • (Boolean) 


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# File 'lib/active_resource/validations.rb', line 279

def valid?
  errors.empty?
end