module ActiveRecord::Core
Public Class Methods
# File activerecord/lib/active_record/core.rb, line 51 def self.configurations @@configurations end
Returns fully resolved configurations hash
# File activerecord/lib/active_record/core.rb, line 45 def self.configurations=(config) @@configurations = ActiveRecord::ConnectionHandling::MergeAndResolveDefaultUrlConfig.new(config).resolve end
Contains the database configuration - as is typically stored in config/database.yml - as a Hash.
For example, the following database.yml…
development: adapter: sqlite3 database: db/development.sqlite3 production: adapter: sqlite3 database: db/production.sqlite3
…would result in ::configurations to look like this:
{
'development' => {
'adapter' => 'sqlite3',
'database' => 'db/development.sqlite3'
},
'production' => {
'adapter' => 'sqlite3',
'database' => 'db/production.sqlite3'
}
}
# File activerecord/lib/active_record/core.rb, line 121 def self.connection_handler ActiveRecord::RuntimeRegistry.connection_handler || default_connection_handler end
# File activerecord/lib/active_record/core.rb, line 125 def self.connection_handler=(handler) ActiveRecord::RuntimeRegistry.connection_handler = handler end
# File activerecord/lib/active_record/core.rb, line 312 def initialize(attributes = nil) self.class.define_attribute_methods @attributes = self.class._default_attributes.deep_dup init_internals initialize_internals_callback assign_attributes(attributes) if attributes yield self if block_given? _run_initialize_callbacks end
New objects can be instantiated as either empty (pass no construction parameter) or pre-set with attributes but not yet saved (pass a hash with key names matching the associated table column names). In both instances, valid attribute keys are determined by the column names of the associated table – hence you can't have attributes that aren't part of the table columns.
Example:
# Instantiates a single new object User.new(first_name: 'Jamie')
Public Instance Methods
# File activerecord/lib/active_record/core.rb, line 457
def <=>(other_object)
if other_object.is_a?(self.class)
self.to_key <=> other_object.to_key
else
super
end
end Allows sort on objects
# File activerecord/lib/active_record/core.rb, line 425
def ==(comparison_object)
super ||
comparison_object.instance_of?(self.class) &&
!id.nil? &&
comparison_object.id == id
end Returns true if comparison_object is the same exact object, or comparison_object is of the same type and self has an ID and it is equal to comparison_object.id.
Note that new records are different from any other record by definition, unless the other record is the receiver itself. Besides, if you fetch existing records with select and leave the ID out, you're on your own, this predicate will return false.
Note also that destroying a record preserves its ID in the model instance, so deleted models are still comparable.
# File activerecord/lib/active_record/core.rb, line 374
Identical to Ruby's clone method. This is a “shallow” copy. Be warned that your attributes are not copied. That means that modifying attributes of the clone will modify the original, since they will both point to the same attributes hash. If you need a copy of your attributes hash, please use the dup method.
user = User.first new_user = user.clone user.name # => "Bob" new_user.name = "Joe" user.name # => "Joe" user.object_id == new_user.object_id # => false user.name.object_id == new_user.name.object_id # => true user.name.object_id == user.dup.name.object_id # => false
# File activerecord/lib/active_record/core.rb, line 476 def connection_handler self.class.connection_handler end
# File activerecord/lib/active_record/core.rb, line 383
Duped objects have no id assigned and are treated as new records. Note that this is a “shallow” copy as it copies the object's attributes only, not its associations. The extent of a “deep” copy is application specific and is therefore left to the application to implement according to its need. The dup method does not preserve the timestamps (created|updated)_(at|on).
# File activerecord/lib/active_record/core.rb, line 408 def encode_with(coder) # FIXME: Remove this when we better serialize attributes coder['raw_attributes'] = attributes_before_type_cast coder['attributes'] = @attributes coder['new_record'] = new_record? coder['active_record_yaml_version'] = 1 end
Populate coder with attributes about this record that should be serialized. The structure of coder defined in this method is guaranteed to match the structure of coder passed to the init_with method.
Example:
class Post < ActiveRecord::Base
end
coder = {}
Post.new.encode_with(coder)
coder # => {"attributes" => {"id" => nil, ... }}
# File activerecord/lib/active_record/core.rb, line 446 def freeze @attributes = @attributes.clone.freeze self end
Clone and freeze the attributes hash such that associations are still accessible, even on destroyed records, but cloned models will not be frozen.
# File activerecord/lib/active_record/core.rb, line 452 def frozen? @attributes.frozen? end
Returns true if the attributes hash has been frozen.
# File activerecord/lib/active_record/core.rb, line 435
def hash
if id
id.hash
else
super
end
end Delegates to id in order to allow two records of the same type and id to work with something like:
[ Person.find(1), Person.find(2), Person.find(3) ] & [ Person.find(1), Person.find(4) ] # => [ Person.find(1) ]
# File activerecord/lib/active_record/core.rb, line 339 def init_with(coder) coder = LegacyYamlAdapter.convert(self.class, coder) @attributes = coder['attributes'] init_internals @new_record = coder['new_record'] self.class.define_attribute_methods yield self if block_given? _run_find_callbacks _run_initialize_callbacks self end
Initialize an empty model object from coder. coder should be the result of previously encoding an Active Record model, using encode_with.
class Post < ActiveRecord::Base
end
old_post = Post.new(title: "hello world")
coder = {}
old_post.encode_with(coder)
post = Post.allocate
post.init_with(coder)
post.title # => 'hello world'
# File activerecord/lib/active_record/core.rb, line 481
def inspect
# We check defined?(@attributes) not to issue warnings if the object is
# allocated but not initialized.
inspection = if defined?(@attributes) && @attributes
self.class.column_names.collect { |name|
if has_attribute?(name)
"#{name}: #{attribute_for_inspect(name)}"
end
}.compact.join(", ")
else
"not initialized"
end
"#<#{self.class} #{inspection}>"
end Returns the contents of the record as a nicely formatted string.
# File activerecord/lib/active_record/core.rb, line 498
def pretty_print(pp)
return super if custom_inspect_method_defined?
pp.object_address_group(self) do
if defined?(@attributes) && @attributes
column_names = self.class.column_names.select { |name| has_attribute?(name) || new_record? }
pp.seplist(column_names, proc { pp.text ',' }) do |column_name|
column_value = read_attribute(column_name)
pp.breakable ' '
pp.group(1) do
pp.text column_name
pp.text ':'
pp.breakable
pp.pp column_value
end
end
else
pp.breakable ' '
pp.text 'not initialized'
end
end
end Takes a PP and prettily prints this record to it, allowing you to get a nice result from pp record when pp is required.
# File activerecord/lib/active_record/core.rb, line 472 def readonly! @readonly = true end
Marks this record as read only.
# File activerecord/lib/active_record/core.rb, line 467 def readonly? @readonly end
Returns true if the record is read only. Records loaded through joins with piggy-back attributes will be marked as read only since they cannot be saved.
# File activerecord/lib/active_record/core.rb, line 521
def slice(*methods)
Hash[methods.map! { |method| [method, public_send(method)] }].with_indifferent_access
end Returns a hash of the given methods with their names as keys and returned values as values.
© 2004–2018 David Heinemeier Hansson
Licensed under the MIT License.