module ActiveRecord::Core

Public Class Methods

action_on_strict_loading_violation() click to toggle source

Set the application to log or raise when an association violates strict loading. Defaults to :raise.

# File lib/active_record/core.rb, line 140
mattr_accessor :action_on_strict_loading_violation, instance_accessor: false, default: :raise

configurations() click to toggle source

Returns fully resolved ActiveRecord::DatabaseConfigurations object

# File lib/active_record/core.rb, line 69
def self.configurations
  @@configurations
end

configurations=(config) click to toggle source

Contains the database configuration - as is typically stored in config/database.yml - as an ActiveRecord::DatabaseConfigurations object.

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:

#<ActiveRecord::DatabaseConfigurations:0x00007fd1acbdf800 @configurations=[
  #<ActiveRecord::DatabaseConfigurations::HashConfig:0x00007fd1acbded10 @env_name="development",
    @name="primary", @config={adapter: "sqlite3", database: "db/development.sqlite3"}>,
  #<ActiveRecord::DatabaseConfigurations::HashConfig:0x00007fd1acbdea90 @env_name="production",
    @name="primary", @config={adapter: "sqlite3", database: "db/production.sqlite3"}>
]>

# File lib/active_record/core.rb, line 63
def self.configurations=(config)
  @@configurations = ActiveRecord::DatabaseConfigurations.new(config)
end

connection_class() click to toggle source

# File lib/active_record/core.rb, line 276
def self.connection_class # :nodoc
  @connection_class ||= false
end

connection_handler() click to toggle source

# File lib/active_record/core.rb, line 175
def self.connection_handler
  Thread.current.thread_variable_get(:ar_connection_handler) || default_connection_handler
end

connection_handler=(handler) click to toggle source

# File lib/active_record/core.rb, line 179
def self.connection_handler=(handler)
  Thread.current.thread_variable_set(:ar_connection_handler, handler)
end

connection_handlers() click to toggle source

# File lib/active_record/core.rb, line 183
def self.connection_handlers
  unless legacy_connection_handling
    raise NotImplementedError, "The new connection handling does not support accessing multiple connection handlers."
  end

  @@connection_handlers ||= {}
end

connection_handlers=(handlers) click to toggle source

# File lib/active_record/core.rb, line 191
def self.connection_handlers=(handlers)
  unless legacy_connection_handling
    raise NotImplementedError, "The new connection handling does not setting support multiple connection handlers."
  end

  @@connection_handlers = handlers
end

current_preventing_writes() click to toggle source

Returns the symbol representing the current setting for preventing writes.

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_preventing_writes #=> true
end

ActiveRecord::Base.connected_to(role: :writing) do
  ActiveRecord::Base.current_preventing_writes #=> false
end

# File lib/active_record/core.rb, line 249
def self.current_preventing_writes
  if legacy_connection_handling
    connection_handler.prevent_writes
  else
    connected_to_stack.reverse_each do |hash|
      return hash[:prevent_writes] if !hash[:prevent_writes].nil? && hash[:klasses].include?(Base)
      return hash[:prevent_writes] if !hash[:prevent_writes].nil? && hash[:klasses].include?(connection_classes)
    end

    false
  end
end

current_role() click to toggle source

Returns the symbol representing the current connected role.

ActiveRecord::Base.connected_to(role: :writing) do
  ActiveRecord::Base.current_role #=> :writing
end

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_role #=> :reading
end

# File lib/active_record/core.rb, line 208
def self.current_role
  if ActiveRecord::Base.legacy_connection_handling
    connection_handlers.key(connection_handler) || default_role
  else
    connected_to_stack.reverse_each do |hash|
      return hash[:role] if hash[:role] && hash[:klasses].include?(Base)
      return hash[:role] if hash[:role] && hash[:klasses].include?(connection_classes)
    end

    default_role
  end
end

current_shard() click to toggle source

Returns the symbol representing the current connected shard.

ActiveRecord::Base.connected_to(role: :reading) do
  ActiveRecord::Base.current_shard #=> :default
end

ActiveRecord::Base.connected_to(role: :writing, shard: :one) do
  ActiveRecord::Base.current_shard #=> :one
end

# File lib/active_record/core.rb, line 230
def self.current_shard
  connected_to_stack.reverse_each do |hash|
    return hash[:shard] if hash[:shard] && hash[:klasses].include?(Base)
    return hash[:shard] if hash[:shard] && hash[:klasses].include?(connection_classes)
  end

  default_shard
end

default_timezone() click to toggle source

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.

# File lib/active_record/core.rb, line 77
mattr_accessor :default_timezone, instance_writer: false, default: :utc

destroy_association_async_job() click to toggle source

Specifies the job used to destroy associations in the background

# File lib/active_record/core.rb, line 39
class_attribute :destroy_association_async_job, instance_writer: false, instance_predicate: false, default: false

dump_schema_after_migration() click to toggle source

Specify whether schema dump should happen at the end of the db:migrate rails command. This is true by default, which is useful for the development environment. This should ideally be false in the production environment where dumping schema is rarely needed.

# File lib/active_record/core.rb, line 107
mattr_accessor :dump_schema_after_migration, instance_writer: false, default: true

dump_schemas() click to toggle source

Specifies which database schemas to dump when calling db:schema:dump. If the value is :schema_search_path (the default), any schemas listed in schema_search_path are dumped. Use :all to dump all schemas regardless of schema_search_path, or a string of comma separated schemas for a custom list.

# File lib/active_record/core.rb, line 116
mattr_accessor :dump_schemas, instance_writer: false, default: :schema_search_path

error_on_ignored_order() click to toggle source

Specifies if an error should be raised if the query has an order being ignored when doing batch queries. Useful in applications where the scope being ignored is error-worthy, rather than a warning.

# File lib/active_record/core.rb, line 94
mattr_accessor :error_on_ignored_order, instance_writer: false, default: false

logger() click to toggle source

Accepts a logger conforming to the interface of Log4r 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.

# File lib/active_record/core.rb, line 20
mattr_accessor :logger, instance_writer: false

new(attributes = nil) { |self| ... } click to toggle source

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')

# File lib/active_record/core.rb, line 518
def initialize(attributes = nil)
  @new_record = true
  @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

queues() click to toggle source

Specifies the names of the queues used by background jobs.

# File lib/active_record/core.rb, line 33
mattr_accessor :queues, instance_accessor: false, default: {}

raise_int_wider_than_64bit() click to toggle source

Application configurable boolean that denotes whether or not to raise an exception when the PostgreSQLAdapter is provided with an integer that is wider than signed 64bit representation

# File lib/active_record/core.rb, line 171
mattr_accessor :raise_int_wider_than_64bit, instance_writer: false, default: true

schema_format() click to toggle source

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.

# File lib/active_record/core.rb, line 87
mattr_accessor :schema_format, instance_writer: false, default: :ruby

suppress_multiple_database_warning() click to toggle source

Show a warning when Rails couldn’t parse your database.yml for multiple databases.

# File lib/active_record/core.rb, line 130
mattr_accessor :suppress_multiple_database_warning, instance_writer: false, default: false

timestamped_migrations() click to toggle source

Specify whether or not to use timestamps for migration versions

# File lib/active_record/core.rb, line 99
mattr_accessor :timestamped_migrations, instance_writer: false, default: true

verbose_query_logs() click to toggle source

Specifies if the methods calling database queries should be logged below their relevant queries. Defaults to false.

# File lib/active_record/core.rb, line 27
mattr_accessor :verbose_query_logs, instance_writer: false, default: false

warn_on_records_fetched_greater_than() click to toggle source

Specify a threshold for the size of query result sets. If the number of records in the set exceeds the threshold, a warning is logged. This can be used to identify queries which load thousands of records and potentially cause memory bloat.

# File lib/active_record/core.rb, line 124
mattr_accessor :warn_on_records_fetched_greater_than, instance_writer: false

Public Instance Methods

<=>(other_object) click to toggle source

Allows sort on objects

Calls superclass method

# File lib/active_record/core.rb, line 669
def <=>(other_object)
  if other_object.is_a?(self.class)
    to_key <=> other_object.to_key
  else
    super
  end
end

==(comparison_object) click to toggle source

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.

Calls superclass method

# File lib/active_record/core.rb, line 637
def ==(comparison_object)
  super ||
    comparison_object.instance_of?(self.class) &&
    !id.nil? &&
    comparison_object.id == id
end

Also aliased as: eql?

clone() click to toggle source

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 lib/active_record/core.rb, line 570

connection_handler() click to toggle source

# File lib/active_record/core.rb, line 711
def connection_handler
  self.class.connection_handler
end

dup() click to toggle source

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 lib/active_record/core.rb, line 587

encode_with(coder) click to toggle source

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 lib/active_record/core.rb, line 622
def encode_with(coder)
  self.class.yaml_encoder.encode(@attributes, coder)
  coder["new_record"] = new_record?
  coder["active_record_yaml_version"] = 2
end

eql?(comparison_object)

Alias for: ==

freeze() click to toggle source

Clone and freeze the attributes hash such that associations are still accessible, even on destroyed records, but cloned models will not be frozen.

# File lib/active_record/core.rb, line 658
def freeze
  @attributes = @attributes.clone.freeze
  self
end

frozen?() click to toggle source

Returns true if the attributes hash has been frozen.

# File lib/active_record/core.rb, line 664
def frozen?
  @attributes.frozen?
end

hash() click to toggle source

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) ]

Calls superclass method

# File lib/active_record/core.rb, line 647
def hash
  if id
    self.class.hash ^ id.hash
  else
    super
  end
end

init_with(coder, &block) click to toggle source

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 lib/active_record/core.rb, line 545
def init_with(coder, &block)
  coder = LegacyYamlAdapter.convert(self.class, coder)
  attributes = self.class.yaml_encoder.decode(coder)
  init_with_attributes(attributes, coder["new_record"], &block)
end

inspect() click to toggle source

Returns the contents of the record as a nicely formatted string.

# File lib/active_record/core.rb, line 716
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.attribute_names.collect do |name|
      if _has_attribute?(name)
        "#{name}: #{attribute_for_inspect(name)}"
      end
    end.compact.join(", ")
  else
    "not initialized"
  end

  "#<#{self.class} #{inspection}>"
end

pretty_print(pp) click to toggle source

Takes a PP and prettily prints this record to it, allowing you to get a nice result from pp record when pp is required.

Calls superclass method

# File lib/active_record/core.rb, line 734
def pretty_print(pp)
  return super if custom_inspect_method_defined?
  pp.object_address_group(self) do
    if defined?(@attributes) && @attributes
      attr_names = self.class.attribute_names.select { |name| _has_attribute?(name) }
      pp.seplist(attr_names, proc { pp.text "," }) do |attr_name|
        pp.breakable " "
        pp.group(1) do
          pp.text attr_name
          pp.text ":"
          pp.breakable
          value = _read_attribute(attr_name)
          value = inspection_filter.filter_param(attr_name, value) unless value.nil?
          pp.pp value
        end
      end
    else
      pp.breakable " "
      pp.text "not initialized"
    end
  end
end

readonly!() click to toggle source

Marks this record as read only.

# File lib/active_record/core.rb, line 707
def readonly!
  @readonly = true
end

readonly?() click to toggle source

Returns true if the record is read only.

# File lib/active_record/core.rb, line 686
def readonly?
  @readonly
end

slice(*methods) click to toggle source

Returns a hash of the given methods with their names as keys and returned values as values.

# File lib/active_record/core.rb, line 758
def slice(*methods)
  methods.flatten.index_with { |method| public_send(method) }.with_indifferent_access
end

strict_loading!() click to toggle source

Sets the record to strict_loading mode. This will raise an error if the record tries to lazily load an association.

user = User.first
user.strict_loading!
user.comments.to_a
=> ActiveRecord::StrictLoadingViolationError

# File lib/active_record/core.rb, line 702
def strict_loading!
  @strict_loading = true
end

strict_loading?() click to toggle source

Returns true if the record is in strict_loading mode.

# File lib/active_record/core.rb, line 691
def strict_loading?
  @strict_loading
end

values_at(*methods) click to toggle source

Returns an array of the values returned by the given methods.

# File lib/active_record/core.rb, line 763
def values_at(*methods)
  methods.flatten.map! { |method| public_send(method) }
end

Private Instance Methods

custom_inspect_method_defined?() click to toggle source

# File lib/active_record/core.rb, line 796
def custom_inspect_method_defined?
  self.class.instance_method(:inspect).owner != ActiveRecord::Base.instance_method(:inspect).owner
end

init_internals() click to toggle source

# File lib/active_record/core.rb, line 780
def init_internals
  @primary_key              = self.class.primary_key
  @readonly                 = false
  @previously_new_record    = false
  @destroyed                = false
  @marked_for_destruction   = false
  @destroyed_by_association = nil
  @_start_transaction_state = nil
  @strict_loading           = self.class.strict_loading_by_default

  self.class.define_attribute_methods
end

initialize_internals_callback() click to toggle source

# File lib/active_record/core.rb, line 793
def initialize_internals_callback
end

inspection_filter() click to toggle source

# File lib/active_record/core.rb, line 807
def inspection_filter
  self.class.inspection_filter
end

to_ary() click to toggle source

+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.

# File lib/active_record/core.rb, line 776
def to_ary
  nil
end