Module: ActiveFedora::AttributeMethods

Extended by:
ActiveSupport::Autoload, ActiveSupport::Concern
Includes:
ActiveModel::AttributeMethods
Included in:
Base, File
Defined in:
lib/active_fedora.rb,
lib/active_fedora/attribute_methods.rb,
lib/active_fedora/attribute_methods/read.rb,
lib/active_fedora/attribute_methods/dirty.rb,
lib/active_fedora/attribute_methods/write.rb

Defined Under Namespace

Modules: ClassMethods, Dirty, Read, Write Classes: GeneratedAttributeMethods

Constant Summary collapse

AttrNames = 
Module.new do
  def self.set_name_cache(name, value)
    const_name = "ATTR_#{name}"
    const_set const_name, value.dup.freeze unless const_defined? const_name
  end
end
BLACKLISTED_CLASS_METHODS = 
%w(private public protected allocate new name parent superclass).freeze

Instance Method Summary collapse

Instance Method Details

#[](attr_name) ⇒ Object

Returns the value of the attribute identified by attr_name after it has been typecast (for example, “2004-12-12” in a date column is cast to a date object, like Date.new(2004, 12, 12)). It raises ActiveModel::MissingAttributeError if the identified attribute is missing.

Alias for the read_attribute method.

class Person < ActiveRecord::Base
  belongs_to :organization
end

person = Person.new(name: 'Francesco', age: '22')
person[:name] # => "Francesco"
person[:age]  # => 22

person = Person.select('id').first
person[:name]            # => ActiveModel::MissingAttributeError: missing attribute: name
person[:organization_id] # => ActiveModel::MissingAttributeError: missing attribute: organization_id



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# File 'lib/active_fedora/attribute_methods.rb', line 225

def [](attr_name)
  read_attribute(attr_name) { |n| missing_attribute(n, caller) }
end

#[]=(attr_name, value) ⇒ Object

Updates the attribute identified by attr_name with the specified value. (Alias for the protected write_attribute method).

class Person < ActiveFedora::Base
end

person = Person.new
person[:age] = '22'
person[:age] # => 22
person[:age] # => Integer



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# File 'lib/active_fedora/attribute_methods.rb', line 239

def []=(attr_name, value)
  write_attribute(attr_name, value)
end

#attribute_for_inspect(attr_name) ⇒ Object

Returns an #inspect-like string for the value of the attribute attr_name. String attributes are truncated up to 50 characters, Date and Time attributes are returned in the :db format, Array attributes are truncated up to 10 values. Other attributes return the value of #inspect without modification.

person = Person.create!(name: 'David Heinemeier Hansson ' * 3)

person.attribute_for_inspect(:name)
# => "\"David Heinemeier Hansson David Heinemeier Hansson ...\""

person.attribute_for_inspect(:created_at)
# => "\"2012-10-22 00:15:07\""

person.attribute_for_inspect(:tag_ids)
# => "[1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...]"



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# File 'lib/active_fedora/attribute_methods.rb', line 173

def attribute_for_inspect(attr_name)
  value = self[attr_name]

  if value.is_a?(String) && value.length > 50
    "#{value[0, 50]}...".inspect
  elsif value.is_a?(Date) || value.is_a?(Time)
    %("#{value.to_s(:db)}")
  elsif value.is_a?(Array) && value.size > 10
    inspected = value.first(10).inspect
    %(#{inspected[0...-1]}, ...])
  else
    value.inspect
  end
end

#attribute_names ⇒ Object

Returns an array of names for the attributes available on this object.

class Person < ActiveFedora::Base
end

person = Person.new
person.attribute_names
# => ["id", "created_at", "updated_at", "name", "age"]



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# File 'lib/active_fedora/attribute_methods.rb', line 138

def attribute_names
  @attributes.keys
end

#attribute_present?(attribute) ⇒ Boolean

Returns true if the specified attribute has been set by the user or by a database load and is neither nil nor empty? (the latter only applies to objects that respond to empty?, most notably Strings). Otherwise, false. Note that it always returns true with boolean attributes.

class Task < ActiveRecord::Base
end

task = Task.new(title: '', is_done: false)
task.attribute_present?(:title)   # => false
task.attribute_present?(:is_done) # => true
task.title = 'Buy milk'
task.is_done = true
task.attribute_present?(:title)   # => true
task.attribute_present?(:is_done) # => true

Returns:

  • (Boolean) 


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# File 'lib/active_fedora/attribute_methods.rb', line 203

def attribute_present?(attribute)
  value = self[attribute]
  !value.nil? && !(value.respond_to?(:empty?) && value.empty?)
end

#attributes ⇒ Object

Returns a hash of all the attributes with their names as keys and the values of the attributes as values.

class Person < ActiveFedora::Base
end

person = Person.create(name: 'Francesco', age: 22)
person.attributes
# => {"id"=>3, "created_at"=>Sun, 21 Oct 2012 04:53:04, "updated_at"=>Sun, 21 Oct 2012 04:53:04, "name"=>"Francesco", "age"=>22}



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# File 'lib/active_fedora/attribute_methods.rb', line 150

def attributes
  attribute_names.each_with_object({}) do |name, attrs|
    attrs[name] = read_attribute(name)
  end
end

#has_attribute?(attr_name) ⇒ Boolean

Returns true if the given attribute is in the attributes hash, otherwise false.

class Person < ActiveRecord::Base
end

person = Person.new
person.has_attribute?(:name)    # => true
person.has_attribute?('age')    # => true
person.has_attribute?(:nothing) # => false

Returns:

  • (Boolean) 


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# File 'lib/active_fedora/attribute_methods.rb', line 126

def has_attribute?(attr_name)
  attribute_names.include?(attr_name.to_s)
end