require 'active_support/concern'
require 'active_support/core_ext/hash/indifferent_access'
require 'active_support/core_ext/object/deep_dup'
require 'thread'
module ActiveRecord
module Core
extend ActiveSupport::Concern
included do
##
# :singleton-method:
# Accepts a logger conforming to the interface of Log4r or the default Ruby 1.8+ Logger class,
# which is then passed on to any new database connections made and which can be retrieved on both
# a class and instance level by calling +logger+.
config_attribute :logger, :global => true
##
# :singleton-method:
# 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 ActiveRecord::Base.configurations to look like this:
#
# {
# 'development' => {
# 'adapter' => 'sqlite3',
# 'database' => 'db/development.sqlite3'
# },
# 'production' => {
# 'adapter' => 'sqlite3',
# 'database' => 'db/production.sqlite3'
# }
# }
config_attribute :configurations, :global => true
self.configurations = {}
##
# :singleton-method:
# Determines whether to use Time.utc (using :utc) or Time.local (using :local) when pulling
# dates and times from the database. This is set to :utc by default.
config_attribute :default_timezone, :global => true
self.default_timezone = :utc
##
# :singleton-method:
# Specifies the format to use when dumping the database schema with Rails'
# Rakefile. If :sql, the schema is dumped as (potentially database-
# specific) SQL statements. If :ruby, the schema is dumped as an
# ActiveRecord::Schema file which can be loaded into any database that
# supports migrations. Use :ruby if you want to have different database
# adapters for, e.g., your development and test environments.
config_attribute :schema_format, :global => true
self.schema_format = :ruby
##
# :singleton-method:
# Specify whether or not to use timestamps for migration versions
config_attribute :timestamped_migrations, :global => true
self.timestamped_migrations = true
##
# :singleton-method:
# The connection handler
config_attribute :connection_handler
self.connection_handler = ConnectionAdapters::ConnectionHandler.new
##
# :singleton-method:
# Specifies wether or not has_many or has_one association option
# :dependent => :restrict raises an exception. If set to true, the
# ActiveRecord::DeleteRestrictionError exception will be raised
# along with a DEPRECATION WARNING. If set to false, an error would
# be added to the model instead.
config_attribute :dependent_restrict_raises, :global => true
self.dependent_restrict_raises = true
end
module ClassMethods
def inherited(child_class) #:nodoc:
child_class.initialize_generated_modules
super
end
def initialize_generated_modules
@attribute_methods_mutex = Mutex.new
# force attribute methods to be higher in inheritance hierarchy than other generated methods
generated_attribute_methods
generated_feature_methods
end
def generated_feature_methods
@generated_feature_methods ||= begin
mod = const_set(:GeneratedFeatureMethods, Module.new)
include mod
mod
end
end
# Returns a string like 'Post(id:integer, title:string, body:text)'
def inspect
if self == Base
super
elsif abstract_class?
"#{super}(abstract)"
elsif table_exists?
attr_list = columns.map { |c| "#{c.name}: #{c.type}" } * ', '
"#{super}(#{attr_list})"
else
"#{super}(Table doesn't exist)"
end
end
# Overwrite the default class equality method to provide support for association proxies.
def ===(object)
object.is_a?(self)
end
def arel_table
@arel_table ||= Arel::Table.new(table_name, arel_engine)
end
def arel_engine
@arel_engine ||= connection_handler.retrieve_connection_pool(self) ? self : active_record_super.arel_engine
end
private
def relation #:nodoc:
relation = Relation.new(self, arel_table)
if finder_needs_type_condition?
relation.where(type_condition).create_with(inheritance_column.to_sym => sti_name)
else
relation
end
end
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.
#
# +initialize+ respects mass-assignment security and accepts either +:as+ or +:without_protection+ options
# in the +options+ parameter.
#
# ==== Examples
# # Instantiates a single new object
# User.new(:first_name => 'Jamie')
#
# # Instantiates a single new object using the :admin mass-assignment security role
# User.new({ :first_name => 'Jamie', :is_admin => true }, :as => :admin)
#
# # Instantiates a single new object bypassing mass-assignment security
# User.new({ :first_name => 'Jamie', :is_admin => true }, :without_protection => true)
def initialize(attributes = nil, options = {})
@attributes = self.class.initialize_attributes(self.class.column_defaults.deep_dup)
@columns_hash = self.class.column_types.dup
init_internals
ensure_proper_type
populate_with_current_scope_attributes
assign_attributes(attributes, options) if attributes
yield self if block_given?
run_callbacks :initialize if _initialize_callbacks.any?
end
# Initialize an empty model object from +coder+. +coder+ must contain
# the attributes necessary for initializing an empty model object. For
# example:
#
# class Post < ActiveRecord::Base
# end
#
# post = Post.allocate
# post.init_with('attributes' => { 'title' => 'hello world' })
# post.title # => 'hello world'
def init_with(coder)
@attributes = self.class.initialize_attributes(coder['attributes'])
@columns_hash = self.class.column_types.merge(coder['column_types'] || {})
init_internals
@new_record = false
run_callbacks :find
run_callbacks :initialize
self
end
# 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).
def initialize_dup(other)
cloned_attributes = other.clone_attributes(:read_attribute_before_type_cast)
self.class.initialize_attributes(cloned_attributes)
cloned_attributes.delete(self.class.primary_key)
@attributes = cloned_attributes
@attributes[self.class.primary_key] = nil
run_callbacks(:initialize) if _initialize_callbacks.any?
@changed_attributes = {}
self.class.column_defaults.each do |attr, orig_value|
@changed_attributes[attr] = orig_value if _field_changed?(attr, orig_value, @attributes[attr])
end
@aggregation_cache = {}
@association_cache = {}
@attributes_cache = {}
@new_record = true
ensure_proper_type
populate_with_current_scope_attributes
super
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, ... }}
def encode_with(coder)
coder['attributes'] = attributes
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.
def ==(comparison_object)
super ||
comparison_object.instance_of?(self.class) &&
id.present? &&
comparison_object.id == id
end
alias :eql? :==
# 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) ]
def hash
id.hash
end
# Freeze the attributes hash such that associations are still accessible, even on destroyed records.
def freeze
@attributes.freeze; self
end
# Returns +true+ if the attributes hash has been frozen.
def frozen?
@attributes.frozen?
end
# Allows sort on objects
def <=>(other_object)
if other_object.is_a?(self.class)
self.to_key <=> other_object.to_key
else
nil
end
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.
def readonly?
@readonly
end
# Marks this record as read only.
def readonly!
@readonly = true
end
# Returns the connection currently associated with the class. This can
# also be used to "borrow" the connection to do database work that isn't
# easily done without going straight to SQL.
def connection
self.class.connection
end
# Returns the contents of the record as a nicely formatted string.
def inspect
inspection = if @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 a hash of the given methods with their names as keys and returned values as values.
def slice(*methods)
Hash[methods.map { |method| [method, public_send(method)] }].with_indifferent_access
end
private
# Under Ruby 1.9, Array#flatten will call #to_ary (recursively) on each of the elements
# of the array, and then rescues from the possible NoMethodError. If those elements are
# ActiveRecord::Base's, then this triggers the various method_missing's that we have,
# which significantly impacts upon performance.
#
# So we can avoid the method_missing hit by explicitly defining #to_ary as nil here.
#
# See also http://tenderlovemaking.com/2011/06/28/til-its-ok-to-return-nil-from-to_ary/
def to_ary # :nodoc:
nil
end
def init_internals
pk = self.class.primary_key
@attributes[pk] = nil unless @attributes.key?(pk)
@aggregation_cache = {}
@association_cache = {}
@attributes_cache = {}
@previously_changed = {}
@changed_attributes = {}
@readonly = false
@destroyed = false
@marked_for_destruction = false
@new_record = true
end
end
end
