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instiki/vendor/rails/activerecord/lib/active_record/base.rb
Jacques Distler 9e909d5be3 Update Rails, rails_xss and Bundler 
Update Bundler to 1.0.15.
Update Rails to 2.3.12.
Update rails_xss plugin.

The latter two were the
source of a considerable
amount of grief, as rails_xss
is now MUCH stricter about what
string methods can be used.

Also made it possible to use
rake 0.9.x with Instiki. But
you probably REALLY want to use

 ruby bundle exec rake ...

instead of just saying

 rake ....
2011-06-15 00:43:38 -05:00

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139 KiB
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require 'yaml'
require 'set'
require 'active_support/core_ext/class/attribute'
module ActiveRecord #:nodoc:
# Generic Active Record exception class.
class ActiveRecordError < StandardError
end
# Raised when the single-table inheritance mechanism fails to locate the subclass
# (for example due to improper usage of column that +inheritance_column+ points to).
class SubclassNotFound < ActiveRecordError #:nodoc:
end
# Raised when an object assigned to an association has an incorrect type.
#
# class Ticket < ActiveRecord::Base
# has_many :patches
# end
#
# class Patch < ActiveRecord::Base
# belongs_to :ticket
# end
#
# # Comments are not patches, this assignment raises AssociationTypeMismatch.
# @ticket.patches << Comment.new(:content => "Please attach tests to your patch.")
class AssociationTypeMismatch < ActiveRecordError
end
# Raised when unserialized object's type mismatches one specified for serializable field.
class SerializationTypeMismatch < ActiveRecordError
end
# Raised when adapter not specified on connection (or configuration file <tt>config/database.yml</tt> misses adapter field).
class AdapterNotSpecified < ActiveRecordError
end
# Raised when Active Record cannot find database adapter specified in <tt>config/database.yml</tt> or programmatically.
class AdapterNotFound < ActiveRecordError
end
# Raised when connection to the database could not been established (for example when <tt>connection=</tt> is given a nil object).
class ConnectionNotEstablished < ActiveRecordError
end
# Raised when Active Record cannot find record by given id or set of ids.
class RecordNotFound < ActiveRecordError
end
# Raised by ActiveRecord::Base.save! and ActiveRecord::Base.create! methods when record cannot be
# saved because record is invalid.
class RecordNotSaved < ActiveRecordError
end
# Raised when SQL statement cannot be executed by the database (for example, it's often the case for MySQL when Ruby driver used is too old).
class StatementInvalid < ActiveRecordError
end
# Raised when number of bind variables in statement given to <tt>:condition</tt> key (for example, when using +find+ method)
# does not match number of expected variables.
#
# For example, in
#
# Location.find :all, :conditions => ["lat = ? AND lng = ?", 53.7362]
#
# two placeholders are given but only one variable to fill them.
class PreparedStatementInvalid < ActiveRecordError
end
# Raised on attempt to save stale record. Record is stale when it's being saved in another query after
# instantiation, for example, when two users edit the same wiki page and one starts editing and saves
# the page before the other.
#
# Read more about optimistic locking in ActiveRecord::Locking module RDoc.
class StaleObjectError < ActiveRecordError
end
# Raised when association is being configured improperly or
# user tries to use offset and limit together with has_many or has_and_belongs_to_many associations.
class ConfigurationError < ActiveRecordError
end
# Raised on attempt to update record that is instantiated as read only.
class ReadOnlyRecord < ActiveRecordError
end
# ActiveRecord::Transactions::ClassMethods.transaction uses this exception
# to distinguish a deliberate rollback from other exceptional situations.
# Normally, raising an exception will cause the +transaction+ method to rollback
# the database transaction *and* pass on the exception. But if you raise an
# ActiveRecord::Rollback exception, then the database transaction will be rolled back,
# without passing on the exception.
#
# For example, you could do this in your controller to rollback a transaction:
#
# class BooksController < ActionController::Base
# def create
# Book.transaction do
# book = Book.new(params[:book])
# book.save!
# if today_is_friday?
# # The system must fail on Friday so that our support department
# # won't be out of job. We silently rollback this transaction
# # without telling the user.
# raise ActiveRecord::Rollback, "Call tech support!"
# end
# end
# # ActiveRecord::Rollback is the only exception that won't be passed on
# # by ActiveRecord::Base.transaction, so this line will still be reached
# # even on Friday.
# redirect_to root_url
# end
# end
class Rollback < ActiveRecordError
end
# Raised when attribute has a name reserved by Active Record (when attribute has name of one of Active Record instance methods).
class DangerousAttributeError < ActiveRecordError
end
# Raised when you've tried to access a column which wasn't loaded by your finder.
# Typically this is because <tt>:select</tt> has been specified.
class MissingAttributeError < NoMethodError
end
# Raised when unknown attributes are supplied via mass assignment.
class UnknownAttributeError < NoMethodError
end
# Raised when an error occurred while doing a mass assignment to an attribute through the
# <tt>attributes=</tt> method. The exception has an +attribute+ property that is the name of the
# offending attribute.
class AttributeAssignmentError < ActiveRecordError
attr_reader :exception, :attribute
def initialize(message, exception, attribute)
@exception = exception
@attribute = attribute
@message = message
end
end
# Raised when there are multiple errors while doing a mass assignment through the +attributes+
# method. The exception has an +errors+ property that contains an array of AttributeAssignmentError
# objects, each corresponding to the error while assigning to an attribute.
class MultiparameterAssignmentErrors < ActiveRecordError
attr_reader :errors
def initialize(errors)
@errors = errors
end
end
# Active Record objects don't specify their attributes directly, but rather infer them from the table definition with
# which they're linked. Adding, removing, and changing attributes and their type is done directly in the database. Any change
# is instantly reflected in the Active Record objects. The mapping that binds a given Active Record class to a certain
# database table will happen automatically in most common cases, but can be overwritten for the uncommon ones.
#
# See the mapping rules in table_name and the full example in link:files/README.html for more insight.
#
# == Creation
#
# Active Records accept constructor parameters either in a hash or as a block. The hash method is especially useful when
# you're receiving the data from somewhere else, like an HTTP request. It works like this:
#
# user = User.new(:name => "David", :occupation => "Code Artist")
# user.name # => "David"
#
# You can also use block initialization:
#
# user = User.new do |u|
# u.name = "David"
# u.occupation = "Code Artist"
# end
#
# And of course you can just create a bare object and specify the attributes after the fact:
#
# user = User.new
# user.name = "David"
# user.occupation = "Code Artist"
#
# == Conditions
#
# Conditions can either be specified as a string, array, or hash representing the WHERE-part of an SQL statement.
# The array form is to be used when the condition input is tainted and requires sanitization. The string form can
# be used for statements that don't involve tainted data. The hash form works much like the array form, except
# only equality and range is possible. Examples:
#
# class User < ActiveRecord::Base
# def self.authenticate_unsafely(user_name, password)
# find(:first, :conditions => "user_name = '#{user_name}' AND password = '#{password}'")
# end
#
# def self.authenticate_safely(user_name, password)
# find(:first, :conditions => [ "user_name = ? AND password = ?", user_name, password ])
# end
#
# def self.authenticate_safely_simply(user_name, password)
# find(:first, :conditions => { :user_name => user_name, :password => password })
# end
# end
#
# The <tt>authenticate_unsafely</tt> method inserts the parameters directly into the query and is thus susceptible to SQL-injection
# attacks if the <tt>user_name</tt> and +password+ parameters come directly from an HTTP request. The <tt>authenticate_safely</tt> and
# <tt>authenticate_safely_simply</tt> both will sanitize the <tt>user_name</tt> and +password+ before inserting them in the query,
# which will ensure that an attacker can't escape the query and fake the login (or worse).
#
# When using multiple parameters in the conditions, it can easily become hard to read exactly what the fourth or fifth
# question mark is supposed to represent. In those cases, you can resort to named bind variables instead. That's done by replacing
# the question marks with symbols and supplying a hash with values for the matching symbol keys:
#
# Company.find(:first, :conditions => [
# "id = :id AND name = :name AND division = :division AND created_at > :accounting_date",
# { :id => 3, :name => "37signals", :division => "First", :accounting_date => '2005-01-01' }
# ])
#
# Similarly, a simple hash without a statement will generate conditions based on equality with the SQL AND
# operator. For instance:
#
# Student.find(:all, :conditions => { :first_name => "Harvey", :status => 1 })
# Student.find(:all, :conditions => params[:student])
#
# A range may be used in the hash to use the SQL BETWEEN operator:
#
# Student.find(:all, :conditions => { :grade => 9..12 })
#
# An array may be used in the hash to use the SQL IN operator:
#
# Student.find(:all, :conditions => { :grade => [9,11,12] })
#
# == Overwriting default accessors
#
# All column values are automatically available through basic accessors on the Active Record object, but sometimes you
# want to specialize this behavior. This can be done by overwriting the default accessors (using the same
# name as the attribute) and calling <tt>read_attribute(attr_name)</tt> and <tt>write_attribute(attr_name, value)</tt> to actually change things.
# Example:
#
# class Song < ActiveRecord::Base
# # Uses an integer of seconds to hold the length of the song
#
# def length=(minutes)
# write_attribute(:length, minutes.to_i * 60)
# end
#
# def length
# read_attribute(:length) / 60
# end
# end
#
# You can alternatively use <tt>self[:attribute]=(value)</tt> and <tt>self[:attribute]</tt> instead of <tt>write_attribute(:attribute, value)</tt> and
# <tt>read_attribute(:attribute)</tt> as a shorter form.
#
# == Attribute query methods
#
# In addition to the basic accessors, query methods are also automatically available on the Active Record object.
# Query methods allow you to test whether an attribute value is present.
#
# For example, an Active Record User with the <tt>name</tt> attribute has a <tt>name?</tt> method that you can call
# to determine whether the user has a name:
#
# user = User.new(:name => "David")
# user.name? # => true
#
# anonymous = User.new(:name => "")
# anonymous.name? # => false
#
# == Accessing attributes before they have been typecasted
#
# Sometimes you want to be able to read the raw attribute data without having the column-determined typecast run its course first.
# That can be done by using the <tt><attribute>_before_type_cast</tt> accessors that all attributes have. For example, if your Account model
# has a <tt>balance</tt> attribute, you can call <tt>account.balance_before_type_cast</tt> or <tt>account.id_before_type_cast</tt>.
#
# This is especially useful in validation situations where the user might supply a string for an integer field and you want to display
# the original string back in an error message. Accessing the attribute normally would typecast the string to 0, which isn't what you
# want.
#
# == Dynamic attribute-based finders
#
# Dynamic attribute-based finders are a cleaner way of getting (and/or creating) objects by simple queries without turning to SQL. They work by
# appending the name of an attribute to <tt>find_by_</tt>, <tt>find_last_by_</tt>, or <tt>find_all_by_</tt>, so you get finders like <tt>Person.find_by_user_name</tt>,
# <tt>Person.find_all_by_last_name</tt>, and <tt>Payment.find_by_transaction_id</tt>. So instead of writing
# <tt>Person.find(:first, :conditions => ["user_name = ?", user_name])</tt>, you just do <tt>Person.find_by_user_name(user_name)</tt>.
# And instead of writing <tt>Person.find(:all, :conditions => ["last_name = ?", last_name])</tt>, you just do <tt>Person.find_all_by_last_name(last_name)</tt>.
#
# It's also possible to use multiple attributes in the same find by separating them with "_and_", so you get finders like
# <tt>Person.find_by_user_name_and_password</tt> or even <tt>Payment.find_by_purchaser_and_state_and_country</tt>. So instead of writing
# <tt>Person.find(:first, :conditions => ["user_name = ? AND password = ?", user_name, password])</tt>, you just do
# <tt>Person.find_by_user_name_and_password(user_name, password)</tt>.
#
# It's even possible to use all the additional parameters to find. For example, the full interface for <tt>Payment.find_all_by_amount</tt>
# is actually <tt>Payment.find_all_by_amount(amount, options)</tt>. And the full interface to <tt>Person.find_by_user_name</tt> is
# actually <tt>Person.find_by_user_name(user_name, options)</tt>. So you could call <tt>Payment.find_all_by_amount(50, :order => "created_on")</tt>.
# Also you may call <tt>Payment.find_last_by_amount(amount, options)</tt> returning the last record matching that amount and options.
#
# The same dynamic finder style can be used to create the object if it doesn't already exist. This dynamic finder is called with
# <tt>find_or_create_by_</tt> and will return the object if it already exists and otherwise creates it, then returns it. Protected attributes won't be set unless they are given in a block. For example:
#
# # No 'Summer' tag exists
# Tag.find_or_create_by_name("Summer") # equal to Tag.create(:name => "Summer")
#
# # Now the 'Summer' tag does exist
# Tag.find_or_create_by_name("Summer") # equal to Tag.find_by_name("Summer")
#
# # Now 'Bob' exist and is an 'admin'
# User.find_or_create_by_name('Bob', :age => 40) { |u| u.admin = true }
#
# Use the <tt>find_or_initialize_by_</tt> finder if you want to return a new record without saving it first. Protected attributes won't be set unless they are given in a block. For example:
#
# # No 'Winter' tag exists
# winter = Tag.find_or_initialize_by_name("Winter")
# winter.new_record? # true
#
# To find by a subset of the attributes to be used for instantiating a new object, pass a hash instead of
# a list of parameters. For example:
#
# Tag.find_or_create_by_name(:name => "rails", :creator => current_user)
#
# That will either find an existing tag named "rails", or create a new one while setting the user that created it.
#
# == Saving arrays, hashes, and other non-mappable objects in text columns
#
# Active Record can serialize any object in text columns using YAML. To do so, you must specify this with a call to the class method +serialize+.
# This makes it possible to store arrays, hashes, and other non-mappable objects without doing any additional work. Example:
#
# class User < ActiveRecord::Base
# serialize :preferences
# end
#
# user = User.create(:preferences => { "background" => "black", "display" => large })
# User.find(user.id).preferences # => { "background" => "black", "display" => large }
#
# You can also specify a class option as the second parameter that'll raise an exception if a serialized object is retrieved as a
# descendant of a class not in the hierarchy. Example:
#
# class User < ActiveRecord::Base
# serialize :preferences, Hash
# end
#
# user = User.create(:preferences => %w( one two three ))
# User.find(user.id).preferences # raises SerializationTypeMismatch
#
# == Single table inheritance
#
# Active Record allows inheritance by storing the name of the class in a column that by default is named "type" (can be changed
# by overwriting <tt>Base.inheritance_column</tt>). This means that an inheritance looking like this:
#
# class Company < ActiveRecord::Base; end
# class Firm < Company; end
# class Client < Company; end
# class PriorityClient < Client; end
#
# When you do <tt>Firm.create(:name => "37signals")</tt>, this record will be saved in the companies table with type = "Firm". You can then
# fetch this row again using <tt>Company.find(:first, "name = '37signals'")</tt> and it will return a Firm object.
#
# If you don't have a type column defined in your table, single-table inheritance won't be triggered. In that case, it'll work just
# like normal subclasses with no special magic for differentiating between them or reloading the right type with find.
#
# Note, all the attributes for all the cases are kept in the same table. Read more:
# http://www.martinfowler.com/eaaCatalog/singleTableInheritance.html
#
# == Connection to multiple databases in different models
#
# Connections are usually created through ActiveRecord::Base.establish_connection and retrieved by ActiveRecord::Base.connection.
# All classes inheriting from ActiveRecord::Base will use this connection. But you can also set a class-specific connection.
# For example, if Course is an ActiveRecord::Base, but resides in a different database, you can just say <tt>Course.establish_connection</tt>
# and Course and all of its subclasses will use this connection instead.
#
# This feature is implemented by keeping a connection pool in ActiveRecord::Base that is a Hash indexed by the class. If a connection is
# requested, the retrieve_connection method will go up the class-hierarchy until a connection is found in the connection pool.
#
# == Exceptions
#
# * ActiveRecordError - Generic error class and superclass of all other errors raised by Active Record.
# * AdapterNotSpecified - The configuration hash used in <tt>establish_connection</tt> didn't include an
# <tt>:adapter</tt> key.
# * AdapterNotFound - The <tt>:adapter</tt> key used in <tt>establish_connection</tt> specified a non-existent adapter
# (or a bad spelling of an existing one).
# * AssociationTypeMismatch - The object assigned to the association wasn't of the type specified in the association definition.
# * SerializationTypeMismatch - The serialized object wasn't of the class specified as the second parameter.
# * ConnectionNotEstablished+ - No connection has been established. Use <tt>establish_connection</tt> before querying.
# * RecordNotFound - No record responded to the +find+ method. Either the row with the given ID doesn't exist
# or the row didn't meet the additional restrictions. Some +find+ calls do not raise this exception to signal
# nothing was found, please check its documentation for further details.
# * StatementInvalid - The database server rejected the SQL statement. The precise error is added in the message.
# * MultiparameterAssignmentErrors - Collection of errors that occurred during a mass assignment using the
# <tt>attributes=</tt> method. The +errors+ property of this exception contains an array of AttributeAssignmentError
# objects that should be inspected to determine which attributes triggered the errors.
# * AttributeAssignmentError - An error occurred while doing a mass assignment through the <tt>attributes=</tt> method.
# You can inspect the +attribute+ property of the exception object to determine which attribute triggered the error.
#
# *Note*: The attributes listed are class-level attributes (accessible from both the class and instance level).
# So it's possible to assign a logger to the class through <tt>Base.logger=</tt> which will then be used by all
# instances in the current object space.
class Base
##
# :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+.
cattr_accessor :logger, :instance_writer => false
def self.inherited(child) #:nodoc:
@@subclasses[self] ||= []
@@subclasses[self] << child
super
end
def self.reset_subclasses #:nodoc:
nonreloadables = []
subclasses.each do |klass|
unless ActiveSupport::Dependencies.autoloaded? klass
nonreloadables << klass
next
end
klass.instance_variables.each { |var| klass.send(:remove_instance_variable, var) }
klass.instance_methods(false).each { |m| klass.send :undef_method, m }
end
@@subclasses = {}
nonreloadables.each { |klass| (@@subclasses[klass.superclass] ||= []) << klass }
end
@@subclasses = {}
##
# :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'
# }
# }
cattr_accessor :configurations, :instance_writer => false
@@configurations = {}
##
# :singleton-method:
# Accessor for the prefix type that will be prepended to every primary key column name. The options are :table_name and
# :table_name_with_underscore. If the first is specified, the Product class will look for "productid" instead of "id" as
# the primary column. If the latter is specified, the Product class will look for "product_id" instead of "id". Remember
# that this is a global setting for all Active Records.
cattr_accessor :primary_key_prefix_type, :instance_writer => false
@@primary_key_prefix_type = nil
##
# :singleton-method:
# Accessor for the name of the prefix string to prepend to every table name. So if set to "basecamp_", all
# table names will be named like "basecamp_projects", "basecamp_people", etc. This is a convenient way of creating a namespace
# for tables in a shared database. By default, the prefix is the empty string.
#
# If you are organising your models within modules you can add a prefix to the models within a namespace by defining
# a singleton method in the parent module called table_name_prefix which returns your chosen prefix.
cattr_accessor :table_name_prefix, :instance_writer => false
@@table_name_prefix = ""
##
# :singleton-method:
# Works like +table_name_prefix+, but appends instead of prepends (set to "_basecamp" gives "projects_basecamp",
# "people_basecamp"). By default, the suffix is the empty string.
cattr_accessor :table_name_suffix, :instance_writer => false
@@table_name_suffix = ""
##
# :singleton-method:
# Indicates whether table names should be the pluralized versions of the corresponding class names.
# If true, the default table name for a Product class will be +products+. If false, it would just be +product+.
# See table_name for the full rules on table/class naming. This is true, by default.
cattr_accessor :pluralize_table_names, :instance_writer => false
@@pluralize_table_names = true
##
# :singleton-method:
# Determines whether to use ANSI codes to colorize the logging statements committed by the connection adapter. These colors
# make it much easier to overview things during debugging (when used through a reader like +tail+ and on a black background), but
# may complicate matters if you use software like syslog. This is true, by default.
cattr_accessor :colorize_logging, :instance_writer => false
@@colorize_logging = true
##
# :singleton-method:
# Determines whether to use Time.local (using :local) or Time.utc (using :utc) when pulling dates and times from the database.
# This is set to :local by default.
cattr_accessor :default_timezone, :instance_writer => false
@@default_timezone = :local
##
# :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.
cattr_accessor :schema_format , :instance_writer => false
@@schema_format = :ruby
##
# :singleton-method:
# Specify whether or not to use timestamps for migration numbers
cattr_accessor :timestamped_migrations , :instance_writer => false
@@timestamped_migrations = true
# Determine whether to store the full constant name including namespace when using STI
class_attribute :store_full_sti_class
self.store_full_sti_class = false
# Stores the default scope for the class
class_inheritable_accessor :default_scoping, :instance_writer => false
self.default_scoping = []
class << self # Class methods
# Find operates with four different retrieval approaches:
#
# * Find by id - This can either be a specific id (1), a list of ids (1, 5, 6), or an array of ids ([5, 6, 10]).
# If no record can be found for all of the listed ids, then RecordNotFound will be raised.
# * Find first - This will return the first record matched by the options used. These options can either be specific
# conditions or merely an order. If no record can be matched, +nil+ is returned. Use
# <tt>Model.find(:first, *args)</tt> or its shortcut <tt>Model.first(*args)</tt>.
# * Find last - This will return the last record matched by the options used. These options can either be specific
# conditions or merely an order. If no record can be matched, +nil+ is returned. Use
# <tt>Model.find(:last, *args)</tt> or its shortcut <tt>Model.last(*args)</tt>.
# * Find all - This will return all the records matched by the options used.
# If no records are found, an empty array is returned. Use
# <tt>Model.find(:all, *args)</tt> or its shortcut <tt>Model.all(*args)</tt>.
#
# All approaches accept an options hash as their last parameter.
#
# ==== Parameters
#
# * <tt>:conditions</tt> - An SQL fragment like "administrator = 1", <tt>[ "user_name = ?", username ]</tt>, or <tt>["user_name = :user_name", { :user_name => user_name }]</tt>. See conditions in the intro.
# * <tt>:order</tt> - An SQL fragment like "created_at DESC, name".
# * <tt>:group</tt> - An attribute name by which the result should be grouped. Uses the <tt>GROUP BY</tt> SQL-clause.
# * <tt>:having</tt> - Combined with +:group+ this can be used to filter the records that a <tt>GROUP BY</tt> returns. Uses the <tt>HAVING</tt> SQL-clause.
# * <tt>:limit</tt> - An integer determining the limit on the number of rows that should be returned.
# * <tt>:offset</tt> - An integer determining the offset from where the rows should be fetched. So at 5, it would skip rows 0 through 4.
# * <tt>:joins</tt> - Either an SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id" (rarely needed),
# named associations in the same form used for the <tt>:include</tt> option, which will perform an <tt>INNER JOIN</tt> on the associated table(s),
# or an array containing a mixture of both strings and named associations.
# If the value is a string, then the records will be returned read-only since they will have attributes that do not correspond to the table's columns.
# Pass <tt>:readonly => false</tt> to override.
# * <tt>:include</tt> - Names associations that should be loaded alongside. The symbols named refer
# to already defined associations. See eager loading under Associations.
# * <tt>:select</tt> - By default, this is "*" as in "SELECT * FROM", but can be changed if you, for example, want to do a join but not
# include the joined columns. Takes a string with the SELECT SQL fragment (e.g. "id, name").
# * <tt>:from</tt> - By default, this is the table name of the class, but can be changed to an alternate table name (or even the name
# of a database view).
# * <tt>:readonly</tt> - Mark the returned records read-only so they cannot be saved or updated.
# * <tt>:lock</tt> - An SQL fragment like "FOR UPDATE" or "LOCK IN SHARE MODE".
# <tt>:lock => true</tt> gives connection's default exclusive lock, usually "FOR UPDATE".
#
# ==== Examples
#
# # find by id
# Person.find(1) # returns the object for ID = 1
# Person.find(1, 2, 6) # returns an array for objects with IDs in (1, 2, 6)
# Person.find([7, 17]) # returns an array for objects with IDs in (7, 17)
# Person.find([1]) # returns an array for the object with ID = 1
# Person.find(1, :conditions => "administrator = 1", :order => "created_on DESC")
#
# Note that returned records may not be in the same order as the ids you
# provide since database rows are unordered. Give an explicit <tt>:order</tt>
# to ensure the results are sorted.
#
# ==== Examples
#
# # find first
# Person.find(:first) # returns the first object fetched by SELECT * FROM people
# Person.find(:first, :conditions => [ "user_name = ?", user_name])
# Person.find(:first, :conditions => [ "user_name = :u", { :u => user_name }])
# Person.find(:first, :order => "created_on DESC", :offset => 5)
#
# # find last
# Person.find(:last) # returns the last object fetched by SELECT * FROM people
# Person.find(:last, :conditions => [ "user_name = ?", user_name])
# Person.find(:last, :order => "created_on DESC", :offset => 5)
#
# # find all
# Person.find(:all) # returns an array of objects for all the rows fetched by SELECT * FROM people
# Person.find(:all, :conditions => [ "category IN (?)", categories], :limit => 50)
# Person.find(:all, :conditions => { :friends => ["Bob", "Steve", "Fred"] }
# Person.find(:all, :offset => 10, :limit => 10)
# Person.find(:all, :include => [ :account, :friends ])
# Person.find(:all, :group => "category")
#
# Example for find with a lock: Imagine two concurrent transactions:
# each will read <tt>person.visits == 2</tt>, add 1 to it, and save, resulting
# in two saves of <tt>person.visits = 3</tt>. By locking the row, the second
# transaction has to wait until the first is finished; we get the
# expected <tt>person.visits == 4</tt>.
#
# Person.transaction do
# person = Person.find(1, :lock => true)
# person.visits += 1
# person.save!
# end
def find(*args)
options = args.extract_options!
validate_find_options(options)
set_readonly_option!(options)
case args.first
when :first then find_initial(options)
when :last then find_last(options)
when :all then find_every(options)
else find_from_ids(args, options)
end
end
# A convenience wrapper for <tt>find(:first, *args)</tt>. You can pass in all the
# same arguments to this method as you can to <tt>find(:first)</tt>.
def first(*args)
find(:first, *args)
end
# A convenience wrapper for <tt>find(:last, *args)</tt>. You can pass in all the
# same arguments to this method as you can to <tt>find(:last)</tt>.
def last(*args)
find(:last, *args)
end
# This is an alias for find(:all). You can pass in all the same arguments to this method as you can
# to find(:all)
def all(*args)
find(:all, *args)
end
# Executes a custom SQL query against your database and returns all the results. The results will
# be returned as an array with columns requested encapsulated as attributes of the model you call
# this method from. If you call <tt>Product.find_by_sql</tt> then the results will be returned in
# a Product object with the attributes you specified in the SQL query.
#
# If you call a complicated SQL query which spans multiple tables the columns specified by the
# SELECT will be attributes of the model, whether or not they are columns of the corresponding
# table.
#
# The +sql+ parameter is a full SQL query as a string. It will be called as is, there will be
# no database agnostic conversions performed. This should be a last resort because using, for example,
# MySQL specific terms will lock you to using that particular database engine or require you to
# change your call if you switch engines.
#
# ==== Examples
# # A simple SQL query spanning multiple tables
# Post.find_by_sql "SELECT p.title, c.author FROM posts p, comments c WHERE p.id = c.post_id"
# > [#<Post:0x36bff9c @attributes={"title"=>"Ruby Meetup", "first_name"=>"Quentin"}>, ...]
#
# # You can use the same string replacement techniques as you can with ActiveRecord#find
# Post.find_by_sql ["SELECT title FROM posts WHERE author = ? AND created > ?", author_id, start_date]
# > [#<Post:0x36bff9c @attributes={"first_name"=>"The Cheap Man Buys Twice"}>, ...]
def find_by_sql(sql)
connection.select_all(sanitize_sql(sql), "#{name} Load").collect! { |record| instantiate(record) }
end
# Returns true if a record exists in the table that matches the +id+ or
# conditions given, or false otherwise. The argument can take five forms:
#
# * Integer - Finds the record with this primary key.
# * String - Finds the record with a primary key corresponding to this
# string (such as <tt>'5'</tt>).
# * Array - Finds the record that matches these +find+-style conditions
# (such as <tt>['color = ?', 'red']</tt>).
# * Hash - Finds the record that matches these +find+-style conditions
# (such as <tt>{:color => 'red'}</tt>).
# * No args - Returns false if the table is empty, true otherwise.
#
# For more information about specifying conditions as a Hash or Array,
# see the Conditions section in the introduction to ActiveRecord::Base.
#
# Note: You can't pass in a condition as a string (like <tt>name =
# 'Jamie'</tt>), since it would be sanitized and then queried against
# the primary key column, like <tt>id = 'name = \'Jamie\''</tt>.
#
# ==== Examples
# Person.exists?(5)
# Person.exists?('5')
# Person.exists?(:name => "David")
# Person.exists?(['name LIKE ?', "%#{query}%"])
# Person.exists?
def exists?(id_or_conditions = {})
find_initial(
:select => "#{quoted_table_name}.#{primary_key}",
:conditions => expand_id_conditions(id_or_conditions)) ? true : false
end
# Creates an object (or multiple objects) and saves it to the database, if validations pass.
# The resulting object is returned whether the object was saved successfully to the database or not.
#
# The +attributes+ parameter can be either be a Hash or an Array of Hashes. These Hashes describe the
# attributes on the objects that are to be created.
#
# ==== Examples
# # Create a single new object
# User.create(:first_name => 'Jamie')
#
# # Create an Array of new objects
# User.create([{ :first_name => 'Jamie' }, { :first_name => 'Jeremy' }])
#
# # Create a single object and pass it into a block to set other attributes.
# User.create(:first_name => 'Jamie') do |u|
# u.is_admin = false
# end
#
# # Creating an Array of new objects using a block, where the block is executed for each object:
# User.create([{ :first_name => 'Jamie' }, { :first_name => 'Jeremy' }]) do |u|
# u.is_admin = false
# end
def create(attributes = nil, &block)
if attributes.is_a?(Array)
attributes.collect { |attr| create(attr, &block) }
else
object = new(attributes)
yield(object) if block_given?
object.save
object
end
end
# Updates an object (or multiple objects) and saves it to the database, if validations pass.
# The resulting object is returned whether the object was saved successfully to the database or not.
#
# ==== Parameters
#
# * +id+ - This should be the id or an array of ids to be updated.
# * +attributes+ - This should be a hash of attributes to be set on the object, or an array of hashes.
#
# ==== Examples
#
# # Updating one record:
# Person.update(15, :user_name => 'Samuel', :group => 'expert')
#
# # Updating multiple records:
# people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } }
# Person.update(people.keys, people.values)
def update(id, attributes)
if id.is_a?(Array)
idx = -1
id.collect { |one_id| idx += 1; update(one_id, attributes[idx]) }
else
object = find(id)
object.update_attributes(attributes)
object
end
end
# Deletes the row with a primary key matching the +id+ argument, using a
# SQL +DELETE+ statement, and returns the number of rows deleted. Active
# Record objects are not instantiated, so the object's callbacks are not
# executed, including any <tt>:dependent</tt> association options or
# Observer methods.
#
# You can delete multiple rows at once by passing an Array of <tt>id</tt>s.
#
# Note: Although it is often much faster than the alternative,
# <tt>#destroy</tt>, skipping callbacks might bypass business logic in
# your application that ensures referential integrity or performs other
# essential jobs.
#
# ==== Examples
#
# # Delete a single row
# Todo.delete(1)
#
# # Delete multiple rows
# Todo.delete([2,3,4])
def delete(id)
delete_all([ "#{connection.quote_column_name(primary_key)} IN (?)", id ])
end
# Destroy an object (or multiple objects) that has the given id, the object is instantiated first,
# therefore all callbacks and filters are fired off before the object is deleted. This method is
# less efficient than ActiveRecord#delete but allows cleanup methods and other actions to be run.
#
# This essentially finds the object (or multiple objects) with the given id, creates a new object
# from the attributes, and then calls destroy on it.
#
# ==== Parameters
#
# * +id+ - Can be either an Integer or an Array of Integers.
#
# ==== Examples
#
# # Destroy a single object
# Todo.destroy(1)
#
# # Destroy multiple objects
# todos = [1,2,3]
# Todo.destroy(todos)
def destroy(id)
if id.is_a?(Array)
id.map { |one_id| destroy(one_id) }
else
find(id).destroy
end
end
# Updates all records with details given if they match a set of conditions supplied, limits and order can
# also be supplied. This method constructs a single SQL UPDATE statement and sends it straight to the
# database. It does not instantiate the involved models and it does not trigger Active Record callbacks.
#
# ==== Parameters
#
# * +updates+ - A string of column and value pairs that will be set on any records that match conditions. This creates the SET clause of the generated SQL.
# * +conditions+ - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro for more info.
# * +options+ - Additional options are <tt>:limit</tt> and <tt>:order</tt>, see the examples for usage.
#
# ==== Examples
#
# # Update all billing objects with the 3 different attributes given
# Billing.update_all( "category = 'authorized', approved = 1, author = 'David'" )
#
# # Update records that match our conditions
# Billing.update_all( "author = 'David'", "title LIKE '%Rails%'" )
#
# # Update records that match our conditions but limit it to 5 ordered by date
# Billing.update_all( "author = 'David'", "title LIKE '%Rails%'",
# :order => 'created_at', :limit => 5 )
def update_all(updates, conditions = nil, options = {})
sql = "UPDATE #{quoted_table_name} SET #{sanitize_sql_for_assignment(updates)} "
scope = scope(:find)
select_sql = ""
add_conditions!(select_sql, conditions, scope)
if options.has_key?(:limit) || (scope && scope[:limit])
# Only take order from scope if limit is also provided by scope, this
# is useful for updating a has_many association with a limit.
add_order!(select_sql, options[:order], scope)
add_limit!(select_sql, options, scope)
sql.concat(connection.limited_update_conditions(select_sql, quoted_table_name, connection.quote_column_name(primary_key)))
else
add_order!(select_sql, options[:order], nil)
sql.concat(select_sql)
end
connection.update(sql, "#{name} Update")
end
# Destroys the records matching +conditions+ by instantiating each
# record and calling its +destroy+ method. Each object's callbacks are
# executed (including <tt>:dependent</tt> association options and
# +before_destroy+/+after_destroy+ Observer methods). Returns the
# collection of objects that were destroyed; each will be frozen, to
# reflect that no changes should be made (since they can't be
# persisted).
#
# Note: Instantiation, callback execution, and deletion of each
# record can be time consuming when you're removing many records at
# once. It generates at least one SQL +DELETE+ query per record (or
# possibly more, to enforce your callbacks). If you want to delete many
# rows quickly, without concern for their associations or callbacks, use
# +delete_all+ instead.
#
# ==== Parameters
#
# * +conditions+ - A string, array, or hash that specifies which records
# to destroy. If omitted, all records are destroyed. See the
# Conditions section in the introduction to ActiveRecord::Base for
# more information.
#
# ==== Examples
#
# Person.destroy_all("last_login < '2004-04-04'")
# Person.destroy_all(:status => "inactive")
def destroy_all(conditions = nil)
find(:all, :conditions => conditions).each { |object| object.destroy }
end
# Deletes the records matching +conditions+ without instantiating the records first, and hence not
# calling the +destroy+ method nor invoking callbacks. This is a single SQL DELETE statement that
# goes straight to the database, much more efficient than +destroy_all+. Be careful with relations
# though, in particular <tt>:dependent</tt> rules defined on associations are not honored. Returns
# the number of rows affected.
#
# ==== Parameters
#
# * +conditions+ - Conditions are specified the same way as with +find+ method.
#
# ==== Example
#
# Post.delete_all("person_id = 5 AND (category = 'Something' OR category = 'Else')")
# Post.delete_all(["person_id = ? AND (category = ? OR category = ?)", 5, 'Something', 'Else'])
#
# Both calls delete the affected posts all at once with a single DELETE statement. If you need to destroy dependent
# associations or call your <tt>before_*</tt> or +after_destroy+ callbacks, use the +destroy_all+ method instead.
def delete_all(conditions = nil)
sql = "DELETE FROM #{quoted_table_name} "
add_conditions!(sql, conditions, scope(:find))
connection.delete(sql, "#{name} Delete all")
end
# Returns the result of an SQL statement that should only include a COUNT(*) in the SELECT part.
# The use of this method should be restricted to complicated SQL queries that can't be executed
# using the ActiveRecord::Calculations class methods. Look into those before using this.
#
# ==== Parameters
#
# * +sql+ - An SQL statement which should return a count query from the database, see the example below.
#
# ==== Examples
#
# Product.count_by_sql "SELECT COUNT(*) FROM sales s, customers c WHERE s.customer_id = c.id"
def count_by_sql(sql)
sql = sanitize_conditions(sql)
connection.select_value(sql, "#{name} Count").to_i
end
# Resets one or more counter caches to their correct value using an SQL
# count query. This is useful when adding new counter caches, or if the
# counter has been corrupted or modified directly by SQL.
#
# ==== Parameters
#
# * +id+ - The id of the object you wish to reset a counter on.
# * +counters+ - One or more counter names to reset
#
# ==== Examples
#
# # For Post with id #1 records reset the comments_count
# Post.reset_counters(1, :comments)
def reset_counters(id, *counters)
object = find(id)
counters.each do |association|
child_class = reflect_on_association(association.to_sym).klass
belongs_name = self.name.demodulize.underscore.to_sym
counter_name = child_class.reflect_on_association(belongs_name).counter_cache_column
value = object.send(association).count
connection.update(<<-CMD, "#{name} UPDATE")
UPDATE #{quoted_table_name}
SET #{connection.quote_column_name(counter_name)} = #{value}
WHERE #{connection.quote_column_name(primary_key)} = #{quote_value(object.id)}
CMD
end
return true
end
# A generic "counter updater" implementation, intended primarily to be
# used by increment_counter and decrement_counter, but which may also
# be useful on its own. It simply does a direct SQL update for the record
# with the given ID, altering the given hash of counters by the amount
# given by the corresponding value:
#
# ==== Parameters
#
# * +id+ - The id of the object you wish to update a counter on or an Array of ids.
# * +counters+ - An Array of Hashes containing the names of the fields
# to update as keys and the amount to update the field by as values.
#
# ==== Examples
#
# # For the Post with id of 5, decrement the comment_count by 1, and
# # increment the action_count by 1
# Post.update_counters 5, :comment_count => -1, :action_count => 1
# # Executes the following SQL:
# # UPDATE posts
# # SET comment_count = comment_count - 1,
# # action_count = action_count + 1
# # WHERE id = 5
#
# # For the Posts with id of 10 and 15, increment the comment_count by 1
# Post.update_counters [10, 15], :comment_count => 1
# # Executes the following SQL:
# # UPDATE posts
# # SET comment_count = comment_count + 1,
# # WHERE id IN (10, 15)
def update_counters(id, counters)
updates = counters.map do |counter_name, value|
operator = value < 0 ? '-' : '+'
quoted_column = connection.quote_column_name(counter_name)
"#{quoted_column} = COALESCE(#{quoted_column}, 0) #{operator} #{value.abs}"
end
update_all(updates.join(', '), primary_key => id )
end
# Increment a number field by one, usually representing a count.
#
# This is used for caching aggregate values, so that they don't need to be computed every time.
# For example, a DiscussionBoard may cache post_count and comment_count otherwise every time the board is
# shown it would have to run an SQL query to find how many posts and comments there are.
#
# ==== Parameters
#
# * +counter_name+ - The name of the field that should be incremented.
# * +id+ - The id of the object that should be incremented.
#
# ==== Examples
#
# # Increment the post_count column for the record with an id of 5
# DiscussionBoard.increment_counter(:post_count, 5)
def increment_counter(counter_name, id)
update_counters(id, counter_name => 1)
end
# Decrement a number field by one, usually representing a count.
#
# This works the same as increment_counter but reduces the column value by 1 instead of increasing it.
#
# ==== Parameters
#
# * +counter_name+ - The name of the field that should be decremented.
# * +id+ - The id of the object that should be decremented.
#
# ==== Examples
#
# # Decrement the post_count column for the record with an id of 5
# DiscussionBoard.decrement_counter(:post_count, 5)
def decrement_counter(counter_name, id)
update_counters(id, counter_name => -1)
end
# Attributes named in this macro are protected from mass-assignment,
# such as <tt>new(attributes)</tt>,
# <tt>update_attributes(attributes)</tt>, or
# <tt>attributes=(attributes)</tt>.
#
# Mass-assignment to these attributes will simply be ignored, to assign
# to them you can use direct writer methods. This is meant to protect
# sensitive attributes from being overwritten by malicious users
# tampering with URLs or forms.
#
# class Customer < ActiveRecord::Base
# attr_protected :credit_rating
# end
#
# customer = Customer.new("name" => David, "credit_rating" => "Excellent")
# customer.credit_rating # => nil
# customer.attributes = { "description" => "Jolly fellow", "credit_rating" => "Superb" }
# customer.credit_rating # => nil
#
# customer.credit_rating = "Average"
# customer.credit_rating # => "Average"
#
# To start from an all-closed default and enable attributes as needed,
# have a look at +attr_accessible+.
def attr_protected(*attributes)
write_inheritable_attribute(:attr_protected, Set.new(attributes.map(&:to_s)) + (protected_attributes || []))
end
# Returns an array of all the attributes that have been protected from mass-assignment.
def protected_attributes # :nodoc:
read_inheritable_attribute(:attr_protected)
end
# Specifies a white list of model attributes that can be set via
# mass-assignment, such as <tt>new(attributes)</tt>,
# <tt>update_attributes(attributes)</tt>, or
# <tt>attributes=(attributes)</tt>
#
# This is the opposite of the +attr_protected+ macro: Mass-assignment
# will only set attributes in this list, to assign to the rest of
# attributes you can use direct writer methods. This is meant to protect
# sensitive attributes from being overwritten by malicious users
# tampering with URLs or forms. If you'd rather start from an all-open
# default and restrict attributes as needed, have a look at
# +attr_protected+.
#
# class Customer < ActiveRecord::Base
# attr_accessible :name, :nickname
# end
#
# customer = Customer.new(:name => "David", :nickname => "Dave", :credit_rating => "Excellent")
# customer.credit_rating # => nil
# customer.attributes = { :name => "Jolly fellow", :credit_rating => "Superb" }
# customer.credit_rating # => nil
#
# customer.credit_rating = "Average"
# customer.credit_rating # => "Average"
def attr_accessible(*attributes)
write_inheritable_attribute(:attr_accessible, Set.new(attributes.map(&:to_s)) + (accessible_attributes || []))
end
# Returns an array of all the attributes that have been made accessible to mass-assignment.
def accessible_attributes # :nodoc:
read_inheritable_attribute(:attr_accessible)
end
# Attributes listed as readonly can be set for a new record, but will be ignored in database updates afterwards.
def attr_readonly(*attributes)
write_inheritable_attribute(:attr_readonly, Set.new(attributes.map(&:to_s)) + (readonly_attributes || []))
end
# Returns an array of all the attributes that have been specified as readonly.
def readonly_attributes
read_inheritable_attribute(:attr_readonly)
end
# If you have an attribute that needs to be saved to the database as an object, and retrieved as the same object,
# then specify the name of that attribute using this method and it will be handled automatically.
# The serialization is done through YAML. If +class_name+ is specified, the serialized object must be of that
# class on retrieval or SerializationTypeMismatch will be raised.
#
# ==== Parameters
#
# * +attr_name+ - The field name that should be serialized.
# * +class_name+ - Optional, class name that the object type should be equal to.
#
# ==== Example
# # Serialize a preferences attribute
# class User
# serialize :preferences
# end
def serialize(attr_name, class_name = Object)
serialized_attributes[attr_name.to_s] = class_name
end
# Returns a hash of all the attributes that have been specified for serialization as keys and their class restriction as values.
def serialized_attributes
read_inheritable_attribute(:attr_serialized) or write_inheritable_attribute(:attr_serialized, {})
end
# Guesses the table name (in forced lower-case) based on the name of the class in the inheritance hierarchy descending
# directly from ActiveRecord::Base. So if the hierarchy looks like: Reply < Message < ActiveRecord::Base, then Message is used
# to guess the table name even when called on Reply. The rules used to do the guess are handled by the Inflector class
# in Active Support, which knows almost all common English inflections. You can add new inflections in config/initializers/inflections.rb.
#
# Nested classes are given table names prefixed by the singular form of
# the parent's table name. Enclosing modules are not considered.
#
# ==== Examples
#
# class Invoice < ActiveRecord::Base; end;
# file class table_name
# invoice.rb Invoice invoices
#
# class Invoice < ActiveRecord::Base; class Lineitem < ActiveRecord::Base; end; end;
# file class table_name
# invoice.rb Invoice::Lineitem invoice_lineitems
#
# module Invoice; class Lineitem < ActiveRecord::Base; end; end;
# file class table_name
# invoice/lineitem.rb Invoice::Lineitem lineitems
#
# Additionally, the class-level +table_name_prefix+ is prepended and the
# +table_name_suffix+ is appended. So if you have "myapp_" as a prefix,
# the table name guess for an Invoice class becomes "myapp_invoices".
# Invoice::Lineitem becomes "myapp_invoice_lineitems".
#
# You can also overwrite this class method to allow for unguessable
# links, such as a Mouse class with a link to a "mice" table. Example:
#
# class Mouse < ActiveRecord::Base
# set_table_name "mice"
# end
def table_name
reset_table_name
end
def reset_table_name #:nodoc:
base = base_class
name =
# STI subclasses always use their superclass' table.
unless self == base
base.table_name
else
# Nested classes are prefixed with singular parent table name.
if parent < ActiveRecord::Base && !parent.abstract_class?
contained = parent.table_name
contained = contained.singularize if parent.pluralize_table_names
contained << '_'
end
name = "#{full_table_name_prefix}#{contained}#{undecorated_table_name(base.name)}#{table_name_suffix}"
end
set_table_name(name)
name
end
# Defines the primary key field -- can be overridden in subclasses. Overwriting will negate any effect of the
# primary_key_prefix_type setting, though.
def primary_key
reset_primary_key
end
def reset_primary_key #:nodoc:
key = get_primary_key(base_class.name)
set_primary_key(key)
key
end
def get_primary_key(base_name) #:nodoc:
key = 'id'
case primary_key_prefix_type
when :table_name
key = base_name.to_s.foreign_key(false)
when :table_name_with_underscore
key = base_name.to_s.foreign_key
end
key
end
def full_table_name_prefix #:nodoc:
(parents.detect{ |p| p.respond_to?(:table_name_prefix) } || self).table_name_prefix
end
# Defines the column name for use with single table inheritance
# -- can be set in subclasses like so: self.inheritance_column = "type_id"
def inheritance_column
@inheritance_column ||= "type".freeze
end
# Lazy-set the sequence name to the connection's default. This method
# is only ever called once since set_sequence_name overrides it.
def sequence_name #:nodoc:
reset_sequence_name
end
def reset_sequence_name #:nodoc:
default = connection.default_sequence_name(table_name, primary_key)
set_sequence_name(default)
default
end
# Sets the table name to use to the given value, or (if the value
# is nil or false) to the value returned by the given block.
#
# class Project < ActiveRecord::Base
# set_table_name "project"
# end
def set_table_name(value = nil, &block)
define_attr_method :table_name, value, &block
end
alias :table_name= :set_table_name
# Sets the name of the primary key column to use to the given value,
# or (if the value is nil or false) to the value returned by the given
# block.
#
# class Project < ActiveRecord::Base
# set_primary_key "sysid"
# end
def set_primary_key(value = nil, &block)
define_attr_method :primary_key, value, &block
end
alias :primary_key= :set_primary_key
# Sets the name of the inheritance column to use to the given value,
# or (if the value # is nil or false) to the value returned by the
# given block.
#
# class Project < ActiveRecord::Base
# set_inheritance_column do
# original_inheritance_column + "_id"
# end
# end
def set_inheritance_column(value = nil, &block)
define_attr_method :inheritance_column, value, &block
end
alias :inheritance_column= :set_inheritance_column
# Sets the name of the sequence to use when generating ids to the given
# value, or (if the value is nil or false) to the value returned by the
# given block. This is required for Oracle and is useful for any
# database which relies on sequences for primary key generation.
#
# If a sequence name is not explicitly set when using Oracle or Firebird,
# it will default to the commonly used pattern of: #{table_name}_seq
#
# If a sequence name is not explicitly set when using PostgreSQL, it
# will discover the sequence corresponding to your primary key for you.
#
# class Project < ActiveRecord::Base
# set_sequence_name "projectseq" # default would have been "project_seq"
# end
def set_sequence_name(value = nil, &block)
define_attr_method :sequence_name, value, &block
end
alias :sequence_name= :set_sequence_name
# Turns the +table_name+ back into a class name following the reverse rules of +table_name+.
def class_name(table_name = table_name) # :nodoc:
ActiveSupport::Deprecation.warn("ActiveRecord::Base#class_name is deprecated and will be removed in Rails 3.", caller)
# remove any prefix and/or suffix from the table name
class_name = table_name[table_name_prefix.length..-(table_name_suffix.length + 1)].camelize
class_name = class_name.singularize if pluralize_table_names
class_name
end
# Indicates whether the table associated with this class exists
def table_exists?
connection.table_exists?(table_name)
end
# Returns an array of column objects for the table associated with this class.
def columns
unless defined?(@columns) && @columns
@columns = connection.columns(table_name, "#{name} Columns")
@columns.each { |column| column.primary = column.name == primary_key }
end
@columns
end
# Returns a hash of column objects for the table associated with this class.
def columns_hash
@columns_hash ||= columns.inject({}) { |hash, column| hash[column.name] = column; hash }
end
# Returns an array of column names as strings.
def column_names
@column_names ||= columns.map { |column| column.name }
end
# Returns an array of column objects where the primary id, all columns ending in "_id" or "_count",
# and columns used for single table inheritance have been removed.
def content_columns
@content_columns ||= columns.reject { |c| c.primary || c.name =~ /(_id|_count)$/ || c.name == inheritance_column }
end
# Returns a hash of all the methods added to query each of the columns in the table with the name of the method as the key
# and true as the value. This makes it possible to do O(1) lookups in respond_to? to check if a given method for attribute
# is available.
def column_methods_hash #:nodoc:
@dynamic_methods_hash ||= column_names.inject(Hash.new(false)) do |methods, attr|
attr_name = attr.to_s
methods[attr.to_sym] = attr_name
methods["#{attr}=".to_sym] = attr_name
methods["#{attr}?".to_sym] = attr_name
methods["#{attr}_before_type_cast".to_sym] = attr_name
methods
end
end
# Resets all the cached information about columns, which will cause them
# to be reloaded on the next request.
#
# The most common usage pattern for this method is probably in a migration,
# when just after creating a table you want to populate it with some default
# values, eg:
#
# class CreateJobLevels < ActiveRecord::Migration
# def self.up
# create_table :job_levels do |t|
# t.integer :id
# t.string :name
#
# t.timestamps
# end
#
# JobLevel.reset_column_information
# %w{assistant executive manager director}.each do |type|
# JobLevel.create(:name => type)
# end
# end
#
# def self.down
# drop_table :job_levels
# end
# end
def reset_column_information
generated_methods.each { |name| undef_method(name) }
@column_names = @columns = @columns_hash = @content_columns = @dynamic_methods_hash = @generated_methods = @inheritance_column = nil
end
def reset_column_information_and_inheritable_attributes_for_all_subclasses#:nodoc:
subclasses.each { |klass| klass.reset_inheritable_attributes; klass.reset_column_information }
end
def self_and_descendants_from_active_record#nodoc:
klass = self
classes = [klass]
while klass != klass.base_class
classes << klass = klass.superclass
end
classes
rescue
# OPTIMIZE this rescue is to fix this test: ./test/cases/reflection_test.rb:56:in `test_human_name_for_column'
# Appearantly the method base_class causes some trouble.
# It now works for sure.
[self]
end
# Transforms attribute key names into a more humane format, such as "First name" instead of "first_name". Example:
# Person.human_attribute_name("first_name") # => "First name"
# This used to be depricated in favor of humanize, but is now preferred, because it automatically uses the I18n
# module now.
# Specify +options+ with additional translating options.
def human_attribute_name(attribute_key_name, options = {})
defaults = self_and_descendants_from_active_record.map do |klass|
:"#{klass.name.underscore}.#{attribute_key_name}"
end
defaults << options[:default] if options[:default]
defaults.flatten!
defaults << attribute_key_name.to_s.humanize
options[:count] ||= 1
I18n.translate(defaults.shift, options.merge(:default => defaults, :scope => [:activerecord, :attributes]))
end
# Transform the modelname into a more humane format, using I18n.
# Defaults to the basic humanize method.
# Default scope of the translation is activerecord.models
# Specify +options+ with additional translating options.
def human_name(options = {})
defaults = self_and_descendants_from_active_record.map do |klass|
:"#{klass.name.underscore}"
end
defaults << self.name.humanize
I18n.translate(defaults.shift, {:scope => [:activerecord, :models], :count => 1, :default => defaults}.merge(options))
end
# True if this isn't a concrete subclass needing a STI type condition.
def descends_from_active_record?
if superclass.abstract_class?
superclass.descends_from_active_record?
else
superclass == Base || !columns_hash.include?(inheritance_column)
end
end
def finder_needs_type_condition? #:nodoc:
# This is like this because benchmarking justifies the strange :false stuff
:true == (@finder_needs_type_condition ||= descends_from_active_record? ? :false : :true)
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
def quote_value(value, column = nil) #:nodoc:
connection.quote(value,column)
end
# Used to sanitize objects before they're used in an SQL SELECT statement. Delegates to <tt>connection.quote</tt>.
def sanitize(object) #:nodoc:
connection.quote(object)
end
# Log and benchmark multiple statements in a single block. Example:
#
# Project.benchmark("Creating project") do
# project = Project.create("name" => "stuff")
# project.create_manager("name" => "David")
# project.milestones << Milestone.find(:all)
# end
#
# The benchmark is only recorded if the current level of the logger is less than or equal to the <tt>log_level</tt>,
# which makes it easy to include benchmarking statements in production software that will remain inexpensive because
# the benchmark will only be conducted if the log level is low enough.
#
# The logging of the multiple statements is turned off unless <tt>use_silence</tt> is set to false.
def benchmark(title, log_level = Logger::DEBUG, use_silence = true)
if logger && logger.level <= log_level
result = nil
ms = Benchmark.ms { result = use_silence ? silence { yield } : yield }
logger.add(log_level, '%s (%.1fms)' % [title, ms])
result
else
yield
end
end
# Silences the logger for the duration of the block.
def silence
old_logger_level, logger.level = logger.level, Logger::ERROR if logger
yield
ensure
logger.level = old_logger_level if logger
end
# Overwrite the default class equality method to provide support for association proxies.
def ===(object)
object.is_a?(self)
end
# Returns the base AR subclass that this class descends from. If A
# extends AR::Base, A.base_class will return A. If B descends from A
# through some arbitrarily deep hierarchy, B.base_class will return A.
def base_class
class_of_active_record_descendant(self)
end
# Set this to true if this is an abstract class (see <tt>abstract_class?</tt>).
attr_accessor :abstract_class
# Returns whether this class is a base AR class. If A is a base class and
# B descends from A, then B.base_class will return B.
def abstract_class?
defined?(@abstract_class) && @abstract_class == true
end
def respond_to?(method_id, include_private = false)
if match = DynamicFinderMatch.match(method_id)
return true if all_attributes_exists?(match.attribute_names)
elsif match = DynamicScopeMatch.match(method_id)
return true if all_attributes_exists?(match.attribute_names)
end
super
end
def sti_name
store_full_sti_class ? name : name.demodulize
end
# Merges conditions so that the result is a valid +condition+
def merge_conditions(*conditions)
segments = []
conditions.each do |condition|
unless condition.blank?
sql = sanitize_sql(condition)
segments << sql unless sql.blank?
end
end
"(#{segments.join(') AND (')})" unless segments.empty?
end
private
def find_initial(options)
options.update(:limit => 1)
find_every(options).first
end
def find_last(options)
order = options[:order]
if order
order = reverse_sql_order(order)
elsif !scoped?(:find, :order)
order = "#{table_name}.#{primary_key} DESC"
end
if scoped?(:find, :order)
scope = scope(:find)
original_scoped_order = scope[:order]
scope[:order] = reverse_sql_order(original_scoped_order)
end
begin
find_initial(options.merge({ :order => order }))
ensure
scope[:order] = original_scoped_order if original_scoped_order
end
end
def reverse_sql_order(order_query)
reversed_query = order_query.to_s.split(/,/).each { |s|
if s.match(/\s(asc|ASC)$/)
s.gsub!(/\s(asc|ASC)$/, ' DESC')
elsif s.match(/\s(desc|DESC)$/)
s.gsub!(/\s(desc|DESC)$/, ' ASC')
elsif !s.match(/\s(asc|ASC|desc|DESC)$/)
s.concat(' DESC')
end
}.join(',')
end
def find_every(options)
include_associations = merge_includes(scope(:find, :include), options[:include])
if include_associations.any? && references_eager_loaded_tables?(options)
records = find_with_associations(options)
else
records = find_by_sql(construct_finder_sql(options))
if include_associations.any?
preload_associations(records, include_associations)
end
end
records.each { |record| record.readonly! } if options[:readonly]
records
end
def find_from_ids(ids, options)
expects_array = ids.first.kind_of?(Array)
return ids.first if expects_array && ids.first.empty?
ids = ids.flatten.compact.uniq
case ids.size
when 0
raise RecordNotFound, "Couldn't find #{name} without an ID"
when 1
result = find_one(ids.first, options)
expects_array ? [ result ] : result
else
find_some(ids, options)
end
end
def find_one(id, options)
conditions = " AND (#{sanitize_sql(options[:conditions])})" if options[:conditions]
options.update :conditions => "#{quoted_table_name}.#{connection.quote_column_name(primary_key)} = #{quote_value(id,columns_hash[primary_key])}#{conditions}"
# Use find_every(options).first since the primary key condition
# already ensures we have a single record. Using find_initial adds
# a superfluous :limit => 1.
if result = find_every(options).first
result
else
raise RecordNotFound, "Couldn't find #{name} with ID=#{id}#{conditions}"
end
end
def find_some(ids, options)
conditions = " AND (#{sanitize_sql(options[:conditions])})" if options[:conditions]
ids_list = ids.map { |id| quote_value(id,columns_hash[primary_key]) }.join(',')
options.update :conditions => "#{quoted_table_name}.#{connection.quote_column_name(primary_key)} IN (#{ids_list})#{conditions}"
result = find_every(options)
# Determine expected size from limit and offset, not just ids.size.
expected_size =
if options[:limit] && ids.size > options[:limit]
options[:limit]
else
ids.size
end
# 11 ids with limit 3, offset 9 should give 2 results.
if options[:offset] && (ids.size - options[:offset] < expected_size)
expected_size = ids.size - options[:offset]
end
if result.size == expected_size
result
else
raise RecordNotFound, "Couldn't find all #{name.pluralize} with IDs (#{ids_list})#{conditions} (found #{result.size} results, but was looking for #{expected_size})"
end
end
# Finder methods must instantiate through this method to work with the
# single-table inheritance model that makes it possible to create
# objects of different types from the same table.
def instantiate(record)
object =
if subclass_name = record[inheritance_column]
# No type given.
if subclass_name.empty?
allocate
else
# Ignore type if no column is present since it was probably
# pulled in from a sloppy join.
unless columns_hash.include?(inheritance_column)
allocate
else
begin
compute_type(subclass_name).allocate
rescue NameError
raise SubclassNotFound,
"The single-table inheritance mechanism failed to locate the subclass: '#{record[inheritance_column]}'. " +
"This error is raised because the column '#{inheritance_column}' is reserved for storing the class in case of inheritance. " +
"Please rename this column if you didn't intend it to be used for storing the inheritance class " +
"or overwrite #{self.to_s}.inheritance_column to use another column for that information."
end
end
end
else
allocate
end
object.instance_variable_set("@attributes", record)
object.instance_variable_set("@attributes_cache", Hash.new)
if object.respond_to_without_attributes?(:after_find)
object.send(:callback, :after_find)
end
if object.respond_to_without_attributes?(:after_initialize)
object.send(:callback, :after_initialize)
end
object
end
# Nest the type name in the same module as this class.
# Bar is "MyApp::Business::Bar" relative to MyApp::Business::Foo
def type_name_with_module(type_name)
if store_full_sti_class
type_name
else
(/^::/ =~ type_name) ? type_name : "#{parent.name}::#{type_name}"
end
end
def default_select(qualified)
if qualified
quoted_table_name + '.*'
else
'*'
end
end
def construct_finder_sql(options)
scope = scope(:find)
sql = "SELECT #{options[:select] || (scope && scope[:select]) || default_select(options[:joins] || (scope && scope[:joins]))} "
sql << "FROM #{options[:from] || (scope && scope[:from]) || quoted_table_name} "
add_joins!(sql, options[:joins], scope)
add_conditions!(sql, options[:conditions], scope)
add_group!(sql, options[:group], options[:having], scope)
add_order!(sql, options[:order], scope)
add_limit!(sql, options, scope)
add_lock!(sql, options, scope)
sql
end
# Merges includes so that the result is a valid +include+
def merge_includes(first, second)
(safe_to_array(first) + safe_to_array(second)).uniq
end
def merge_joins(*joins)
if joins.any?{|j| j.is_a?(String) || array_of_strings?(j) }
joins = joins.collect do |join|
join = [join] if join.is_a?(String)
unless array_of_strings?(join)
join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, join, nil)
join = join_dependency.join_associations.collect { |assoc| assoc.association_join }
end
join
end
joins.flatten.map{|j| j.strip}.uniq
else
joins.collect{|j| safe_to_array(j)}.flatten.uniq
end
end
# Object#to_a is deprecated, though it does have the desired behavior
def safe_to_array(o)
case o
when NilClass
[]
when Array
o
else
[o]
end
end
def array_of_strings?(o)
o.is_a?(Array) && o.all?{|obj| obj.is_a?(String)}
end
def add_order!(sql, order, scope = :auto)
scope = scope(:find) if :auto == scope
scoped_order = scope[:order] if scope
if order
sql << " ORDER BY #{order}"
if scoped_order && scoped_order != order
sql << ", #{scoped_order}"
end
else
sql << " ORDER BY #{scoped_order}" if scoped_order
end
end
def add_group!(sql, group, having, scope = :auto)
if group
sql << " GROUP BY #{group}"
sql << " HAVING #{sanitize_sql_for_conditions(having)}" if having
else
scope = scope(:find) if :auto == scope
if scope && (scoped_group = scope[:group])
sql << " GROUP BY #{scoped_group}"
sql << " HAVING #{sanitize_sql_for_conditions(scope[:having])}" if scope[:having]
end
end
end
# The optional scope argument is for the current <tt>:find</tt> scope.
def add_limit!(sql, options, scope = :auto)
scope = scope(:find) if :auto == scope
if scope
options[:limit] ||= scope[:limit]
options[:offset] ||= scope[:offset]
end
connection.add_limit_offset!(sql, options)
end
# The optional scope argument is for the current <tt>:find</tt> scope.
# The <tt>:lock</tt> option has precedence over a scoped <tt>:lock</tt>.
def add_lock!(sql, options, scope = :auto)
scope = scope(:find) if :auto == scope
options = options.reverse_merge(:lock => scope[:lock]) if scope
connection.add_lock!(sql, options)
end
# The optional scope argument is for the current <tt>:find</tt> scope.
def add_joins!(sql, joins, scope = :auto)
scope = scope(:find) if :auto == scope
merged_joins = scope && scope[:joins] && joins ? merge_joins(scope[:joins], joins) : (joins || scope && scope[:joins])
case merged_joins
when Symbol, Hash, Array
if array_of_strings?(merged_joins)
sql << merged_joins.join(' ') + " "
else
join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, merged_joins, nil)
sql << " #{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join} "
end
when String
sql << " #{merged_joins} "
end
end
# Adds a sanitized version of +conditions+ to the +sql+ string. Note that the passed-in +sql+ string is changed.
# The optional scope argument is for the current <tt>:find</tt> scope.
def add_conditions!(sql, conditions, scope = :auto)
scope = scope(:find) if :auto == scope
conditions = [conditions]
conditions << scope[:conditions] if scope
conditions << type_condition if finder_needs_type_condition?
merged_conditions = merge_conditions(*conditions)
sql << "WHERE #{merged_conditions} " unless merged_conditions.blank?
end
def type_condition(table_alias=nil)
quoted_table_alias = self.connection.quote_table_name(table_alias || table_name)
quoted_inheritance_column = connection.quote_column_name(inheritance_column)
type_condition = subclasses.inject("#{quoted_table_alias}.#{quoted_inheritance_column} = '#{sti_name}' ") do |condition, subclass|
condition << "OR #{quoted_table_alias}.#{quoted_inheritance_column} = '#{subclass.sti_name}' "
end
" (#{type_condition}) "
end
# Guesses the table name, but does not decorate it with prefix and suffix information.
def undecorated_table_name(class_name = base_class.name)
table_name = class_name.to_s.demodulize.underscore
table_name = table_name.pluralize if pluralize_table_names
table_name
end
# Enables dynamic finders like <tt>find_by_user_name(user_name)</tt> and <tt>find_by_user_name_and_password(user_name, password)</tt>
# that are turned into <tt>find(:first, :conditions => ["user_name = ?", user_name])</tt> and
# <tt>find(:first, :conditions => ["user_name = ? AND password = ?", user_name, password])</tt> respectively. Also works for
# <tt>find(:all)</tt> by using <tt>find_all_by_amount(50)</tt> that is turned into <tt>find(:all, :conditions => ["amount = ?", 50])</tt>.
#
# It's even possible to use all the additional parameters to +find+. For example, the full interface for +find_all_by_amount+
# is actually <tt>find_all_by_amount(amount, options)</tt>.
#
# Also enables dynamic scopes like scoped_by_user_name(user_name) and scoped_by_user_name_and_password(user_name, password) that
# are turned into scoped(:conditions => ["user_name = ?", user_name]) and scoped(:conditions => ["user_name = ? AND password = ?", user_name, password])
# respectively.
#
# Each dynamic finder, scope or initializer/creator is also defined in the class after it is first invoked, so that future
# attempts to use it do not run through method_missing.
def method_missing(method_id, *arguments, &block)
if match = DynamicFinderMatch.match(method_id)
attribute_names = match.attribute_names
super unless all_attributes_exists?(attribute_names)
if match.finder?
finder = match.finder
bang = match.bang?
# def self.find_by_login_and_activated(*args)
# options = args.extract_options!
# attributes = construct_attributes_from_arguments(
# [:login,:activated],
# args
# )
# finder_options = { :conditions => attributes }
# validate_find_options(options)
# set_readonly_option!(options)
#
# if options[:conditions]
# with_scope(:find => finder_options) do
# find(:first, options)
# end
# else
# find(:first, options.merge(finder_options))
# end
# end
self.class_eval <<-EOS, __FILE__, __LINE__ + 1
def self.#{method_id}(*args)
options = args.extract_options!
attributes = construct_attributes_from_arguments(
[:#{attribute_names.join(',:')}],
args
)
finder_options = { :conditions => attributes }
validate_find_options(options)
set_readonly_option!(options)
#{'result = ' if bang}if options[:conditions]
with_scope(:find => finder_options) do
find(:#{finder}, options)
end
else
find(:#{finder}, options.merge(finder_options))
end
#{'result || raise(RecordNotFound, "Couldn\'t find #{name} with #{attributes.to_a.collect {|pair| "#{pair.first} = #{pair.second}"}.join(\', \')}")' if bang}
end
EOS
send(method_id, *arguments)
elsif match.instantiator?
instantiator = match.instantiator
# def self.find_or_create_by_user_id(*args)
# guard_protected_attributes = false
#
# if args[0].is_a?(Hash)
# guard_protected_attributes = true
# attributes = args[0].with_indifferent_access
# find_attributes = attributes.slice(*[:user_id])
# else
# find_attributes = attributes = construct_attributes_from_arguments([:user_id], args)
# end
#
# options = { :conditions => find_attributes }
# set_readonly_option!(options)
#
# record = find(:first, options)
#
# if record.nil?
# record = self.new { |r| r.send(:attributes=, attributes, guard_protected_attributes) }
# yield(record) if block_given?
# record.save
# record
# else
# record
# end
# end
self.class_eval <<-EOS, __FILE__, __LINE__ + 1
def self.#{method_id}(*args)
attributes = [:#{attribute_names.join(',:')}]
protected_attributes_for_create, unprotected_attributes_for_create = {}, {}
args.each_with_index do |arg, i|
if arg.is_a?(Hash)
protected_attributes_for_create = args[i].with_indifferent_access
else
unprotected_attributes_for_create[attributes[i]] = args[i]
end
end
find_attributes = (protected_attributes_for_create.merge(unprotected_attributes_for_create)).slice(*attributes)
options = { :conditions => find_attributes }
set_readonly_option!(options)
record = find(:first, options)
if record.nil?
record = self.new do |r|
r.send(:attributes=, protected_attributes_for_create, true) unless protected_attributes_for_create.empty?
r.send(:attributes=, unprotected_attributes_for_create, false) unless unprotected_attributes_for_create.empty?
end
#{'yield(record) if block_given?'}
#{'record.save' if instantiator == :create}
record
else
record
end
end
EOS
send(method_id, *arguments, &block)
end
elsif match = DynamicScopeMatch.match(method_id)
attribute_names = match.attribute_names
super unless all_attributes_exists?(attribute_names)
if match.scope?
self.class_eval <<-EOS, __FILE__, __LINE__ + 1
def self.#{method_id}(*args) # def self.scoped_by_user_name_and_password(*args)
options = args.extract_options! # options = args.extract_options!
attributes = construct_attributes_from_arguments( # attributes = construct_attributes_from_arguments(
[:#{attribute_names.join(',:')}], args # [:user_name, :password], args
) # )
#
scoped(:conditions => attributes) # scoped(:conditions => attributes)
end # end
EOS
send(method_id, *arguments)
end
else
super
end
end
def construct_attributes_from_arguments(attribute_names, arguments)
attributes = {}
attribute_names.each_with_index { |name, idx| attributes[name] = arguments[idx] }
attributes
end
# Similar in purpose to +expand_hash_conditions_for_aggregates+.
def expand_attribute_names_for_aggregates(attribute_names)
expanded_attribute_names = []
attribute_names.each do |attribute_name|
unless (aggregation = reflect_on_aggregation(attribute_name.to_sym)).nil?
aggregate_mapping(aggregation).each do |field_attr, aggregate_attr|
expanded_attribute_names << field_attr
end
else
expanded_attribute_names << attribute_name
end
end
expanded_attribute_names
end
def all_attributes_exists?(attribute_names)
attribute_names = expand_attribute_names_for_aggregates(attribute_names)
attribute_names.all? { |name| column_methods_hash.include?(name.to_sym) }
end
def attribute_condition(quoted_column_name, argument)
case argument
when nil then "#{quoted_column_name} IS ?"
when Array, ActiveRecord::Associations::AssociationCollection, ActiveRecord::NamedScope::Scope then "#{quoted_column_name} IN (?)"
when Range then if argument.exclude_end?
"#{quoted_column_name} >= ? AND #{quoted_column_name} < ?"
else
"#{quoted_column_name} BETWEEN ? AND ?"
end
else "#{quoted_column_name} = ?"
end
end
# Interpret Array and Hash as conditions and anything else as an id.
def expand_id_conditions(id_or_conditions)
case id_or_conditions
when Array, Hash then id_or_conditions
else sanitize_sql(primary_key => id_or_conditions)
end
end
# Defines an "attribute" method (like +inheritance_column+ or
# +table_name+). A new (class) method will be created with the
# given name. If a value is specified, the new method will
# return that value (as a string). Otherwise, the given block
# will be used to compute the value of the method.
#
# The original method will be aliased, with the new name being
# prefixed with "original_". This allows the new method to
# access the original value.
#
# Example:
#
# class A < ActiveRecord::Base
# define_attr_method :primary_key, "sysid"
# define_attr_method( :inheritance_column ) do
# original_inheritance_column + "_id"
# end
# end
def define_attr_method(name, value=nil, &block)
sing = class << self; self; end
sing.send :alias_method, "original_#{name}", name
if block_given?
sing.send :define_method, name, &block
else
# use eval instead of a block to work around a memory leak in dev
# mode in fcgi
sing.class_eval "def #{name}; #{value.to_s.inspect}; end"
end
end
protected
# Scope parameters to method calls within the block. Takes a hash of method_name => parameters hash.
# method_name may be <tt>:find</tt> or <tt>:create</tt>. <tt>:find</tt> parameters may include the <tt>:conditions</tt>, <tt>:joins</tt>,
# <tt>:include</tt>, <tt>:offset</tt>, <tt>:limit</tt>, and <tt>:readonly</tt> options. <tt>:create</tt> parameters are an attributes hash.
#
# class Article < ActiveRecord::Base
# def self.create_with_scope
# with_scope(:find => { :conditions => "blog_id = 1" }, :create => { :blog_id => 1 }) do
# find(1) # => SELECT * from articles WHERE blog_id = 1 AND id = 1
# a = create(1)
# a.blog_id # => 1
# end
# end
# end
#
# In nested scopings, all previous parameters are overwritten by the innermost rule, with the exception of
# <tt>:conditions</tt>, <tt>:include</tt>, and <tt>:joins</tt> options in <tt>:find</tt>, which are merged.
#
# <tt>:joins</tt> options are uniqued so multiple scopes can join in the same table without table aliasing
# problems. If you need to join multiple tables, but still want one of the tables to be uniqued, use the
# array of strings format for your joins.
#
# class Article < ActiveRecord::Base
# def self.find_with_scope
# with_scope(:find => { :conditions => "blog_id = 1", :limit => 1 }, :create => { :blog_id => 1 }) do
# with_scope(:find => { :limit => 10 })
# find(:all) # => SELECT * from articles WHERE blog_id = 1 LIMIT 10
# end
# with_scope(:find => { :conditions => "author_id = 3" })
# find(:all) # => SELECT * from articles WHERE blog_id = 1 AND author_id = 3 LIMIT 1
# end
# end
# end
# end
#
# You can ignore any previous scopings by using the <tt>with_exclusive_scope</tt> method.
#
# class Article < ActiveRecord::Base
# def self.find_with_exclusive_scope
# with_scope(:find => { :conditions => "blog_id = 1", :limit => 1 }) do
# with_exclusive_scope(:find => { :limit => 10 })
# find(:all) # => SELECT * from articles LIMIT 10
# end
# end
# end
# end
#
# *Note*: the +:find+ scope also has effect on update and deletion methods,
# like +update_all+ and +delete_all+.
def with_scope(method_scoping = {}, action = :merge, &block)
method_scoping = method_scoping.method_scoping if method_scoping.respond_to?(:method_scoping)
# Dup first and second level of hash (method and params).
method_scoping = method_scoping.inject({}) do |hash, (method, params)|
hash[method] = (params == true) ? params : params.dup
hash
end
method_scoping.assert_valid_keys([ :find, :create ])
if f = method_scoping[:find]
f.assert_valid_keys(VALID_FIND_OPTIONS)
set_readonly_option! f
end
# Merge scopings
if [:merge, :reverse_merge].include?(action) && current_scoped_methods
method_scoping = current_scoped_methods.inject(method_scoping) do |hash, (method, params)|
case hash[method]
when Hash
if method == :find
(hash[method].keys + params.keys).uniq.each do |key|
merge = hash[method][key] && params[key] # merge if both scopes have the same key
if key == :conditions && merge
if params[key].is_a?(Hash) && hash[method][key].is_a?(Hash)
hash[method][key] = merge_conditions(hash[method][key].deep_merge(params[key]))
else
hash[method][key] = merge_conditions(params[key], hash[method][key])
end
elsif key == :include && merge
hash[method][key] = merge_includes(hash[method][key], params[key]).uniq
elsif key == :joins && merge
hash[method][key] = merge_joins(params[key], hash[method][key])
else
hash[method][key] = hash[method][key] || params[key]
end
end
else
if action == :reverse_merge
hash[method] = hash[method].merge(params)
else
hash[method] = params.merge(hash[method])
end
end
else
hash[method] = params
end
hash
end
end
self.scoped_methods << method_scoping
begin
yield
ensure
self.scoped_methods.pop
end
end
# Works like with_scope, but discards any nested properties.
def with_exclusive_scope(method_scoping = {}, &block)
with_scope(method_scoping, :overwrite, &block)
end
def subclasses #:nodoc:
@@subclasses[self] ||= []
@@subclasses[self] + extra = @@subclasses[self].inject([]) {|list, subclass| list + subclass.subclasses }
end
# Sets the default options for the model. The format of the
# <tt>options</tt> argument is the same as in find.
#
# class Person < ActiveRecord::Base
# default_scope :order => 'last_name, first_name'
# end
def default_scope(options = {})
self.default_scoping << { :find => options, :create => options[:conditions].is_a?(Hash) ? options[:conditions] : {} }
end
# Test whether the given method and optional key are scoped.
def scoped?(method, key = nil) #:nodoc:
if current_scoped_methods && (scope = current_scoped_methods[method])
!key || !scope[key].nil?
end
end
# Retrieve the scope for the given method and optional key.
def scope(method, key = nil) #:nodoc:
if current_scoped_methods && (scope = current_scoped_methods[method])
key ? scope[key] : scope
end
end
def scoped_methods #:nodoc:
Thread.current[:"#{self}_scoped_methods"] ||= self.default_scoping.dup
end
def current_scoped_methods #:nodoc:
scoped_methods.last
end
# Returns the class type of the record using the current module as a prefix. So descendants of
# MyApp::Business::Account would appear as MyApp::Business::AccountSubclass.
def compute_type(type_name)
modularized_name = type_name_with_module(type_name)
silence_warnings do
begin
class_eval(modularized_name, __FILE__)
rescue NameError
class_eval(type_name, __FILE__)
end
end
end
# Returns the class descending directly from ActiveRecord::Base or an
# abstract class, if any, in the inheritance hierarchy.
def class_of_active_record_descendant(klass)
if klass.superclass == Base || klass.superclass.abstract_class?
klass
elsif klass.superclass.nil?
raise ActiveRecordError, "#{name} doesn't belong in a hierarchy descending from ActiveRecord"
else
class_of_active_record_descendant(klass.superclass)
end
end
# Returns the name of the class descending directly from Active Record in the inheritance hierarchy.
def class_name_of_active_record_descendant(klass) #:nodoc:
klass.base_class.name
end
# Accepts an array, hash, or string of SQL conditions and sanitizes
# them into a valid SQL fragment for a WHERE clause.
# ["name='%s' and group_id='%s'", "foo'bar", 4] returns "name='foo''bar' and group_id='4'"
# { :name => "foo'bar", :group_id => 4 } returns "name='foo''bar' and group_id='4'"
# "name='foo''bar' and group_id='4'" returns "name='foo''bar' and group_id='4'"
def sanitize_sql_for_conditions(condition, table_name = quoted_table_name)
return nil if condition.blank?
case condition
when Array; sanitize_sql_array(condition)
when Hash; sanitize_sql_hash_for_conditions(condition, table_name)
else condition
end
end
alias_method :sanitize_sql, :sanitize_sql_for_conditions
# Accepts an array, hash, or string of SQL conditions and sanitizes
# them into a valid SQL fragment for a SET clause.
# { :name => nil, :group_id => 4 } returns "name = NULL , group_id='4'"
def sanitize_sql_for_assignment(assignments)
case assignments
when Array; sanitize_sql_array(assignments)
when Hash; sanitize_sql_hash_for_assignment(assignments)
else assignments
end
end
def aggregate_mapping(reflection)
mapping = reflection.options[:mapping] || [reflection.name, reflection.name]
mapping.first.is_a?(Array) ? mapping : [mapping]
end
# Accepts a hash of SQL conditions and replaces those attributes
# that correspond to a +composed_of+ relationship with their expanded
# aggregate attribute values.
# Given:
# class Person < ActiveRecord::Base
# composed_of :address, :class_name => "Address",
# :mapping => [%w(address_street street), %w(address_city city)]
# end
# Then:
# { :address => Address.new("813 abc st.", "chicago") }
# # => { :address_street => "813 abc st.", :address_city => "chicago" }
def expand_hash_conditions_for_aggregates(attrs)
expanded_attrs = {}
attrs.each do |attr, value|
unless (aggregation = reflect_on_aggregation(attr.to_sym)).nil?
mapping = aggregate_mapping(aggregation)
mapping.each do |field_attr, aggregate_attr|
if mapping.size == 1 && !value.respond_to?(aggregate_attr)
expanded_attrs[field_attr] = value
else
expanded_attrs[field_attr] = value.send(aggregate_attr)
end
end
else
expanded_attrs[attr] = value
end
end
expanded_attrs
end
# Sanitizes a hash of attribute/value pairs into SQL conditions for a WHERE clause.
# { :name => "foo'bar", :group_id => 4 }
# # => "name='foo''bar' and group_id= 4"
# { :status => nil, :group_id => [1,2,3] }
# # => "status IS NULL and group_id IN (1,2,3)"
# { :age => 13..18 }
# # => "age BETWEEN 13 AND 18"
# { 'other_records.id' => 7 }
# # => "`other_records`.`id` = 7"
# { :other_records => { :id => 7 } }
# # => "`other_records`.`id` = 7"
# And for value objects on a composed_of relationship:
# { :address => Address.new("123 abc st.", "chicago") }
# # => "address_street='123 abc st.' and address_city='chicago'"
def sanitize_sql_hash_for_conditions(attrs, default_table_name = quoted_table_name)
attrs = expand_hash_conditions_for_aggregates(attrs)
conditions = attrs.map do |attr, value|
table_name = default_table_name
unless value.is_a?(Hash)
attr = attr.to_s
# Extract table name from qualified attribute names.
if attr.include?('.')
attr_table_name, attr = attr.split('.', 2)
attr_table_name = connection.quote_table_name(attr_table_name)
else
attr_table_name = table_name
end
attribute_condition("#{attr_table_name}.#{connection.quote_column_name(attr)}", value)
else
sanitize_sql_hash_for_conditions(value, connection.quote_table_name(attr.to_s))
end
end.join(' AND ')
replace_bind_variables(conditions, expand_range_bind_variables(attrs.values))
end
alias_method :sanitize_sql_hash, :sanitize_sql_hash_for_conditions
# Sanitizes a hash of attribute/value pairs into SQL conditions for a SET clause.
# { :status => nil, :group_id => 1 }
# # => "status = NULL , group_id = 1"
def sanitize_sql_hash_for_assignment(attrs)
attrs.map do |attr, value|
"#{connection.quote_column_name(attr)} = #{quote_bound_value(value)}"
end.join(', ')
end
# Accepts an array of conditions. The array has each value
# sanitized and interpolated into the SQL statement.
# ["name='%s' and group_id='%s'", "foo'bar", 4] returns "name='foo''bar' and group_id='4'"
def sanitize_sql_array(ary)
statement, *values = ary
if values.first.is_a?(Hash) and statement =~ /:\w+/
replace_named_bind_variables(statement, values.first)
elsif statement.include?('?')
replace_bind_variables(statement, values)
else
statement % values.collect { |value| connection.quote_string(value.to_s) }
end
end
alias_method :sanitize_conditions, :sanitize_sql
def replace_bind_variables(statement, values) #:nodoc:
raise_if_bind_arity_mismatch(statement, statement.count('?'), values.size)
bound = values.dup
statement.gsub('?') { quote_bound_value(bound.shift) }
end
def replace_named_bind_variables(statement, bind_vars) #:nodoc:
statement.gsub(/(:?):([a-zA-Z]\w*)/) do
if $1 == ':' # skip postgresql casts
$& # return the whole match
elsif bind_vars.include?(match = $2.to_sym)
quote_bound_value(bind_vars[match])
else
raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}"
end
end
end
def expand_range_bind_variables(bind_vars) #:nodoc:
expanded = []
bind_vars.each do |var|
next if var.is_a?(Hash)
if var.is_a?(Range)
expanded << var.first
expanded << var.last
else
expanded << var
end
end
expanded
end
def quote_bound_value(value) #:nodoc:
if value.respond_to?(:map) && !value.acts_like?(:string)
if value.respond_to?(:empty?) && value.empty?
connection.quote(nil)
else
value.map { |v| connection.quote(v) }.join(',')
end
else
connection.quote(value)
end
end
def raise_if_bind_arity_mismatch(statement, expected, provided) #:nodoc:
unless expected == provided
raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}"
end
end
VALID_FIND_OPTIONS = [ :conditions, :include, :joins, :limit, :offset,
:order, :select, :readonly, :group, :having, :from, :lock ]
def validate_find_options(options) #:nodoc:
options.assert_valid_keys(VALID_FIND_OPTIONS)
end
def set_readonly_option!(options) #:nodoc:
# Inherit :readonly from finder scope if set. Otherwise,
# if :joins is not blank then :readonly defaults to true.
unless options.has_key?(:readonly)
if scoped_readonly = scope(:find, :readonly)
options[:readonly] = scoped_readonly
elsif !options[:joins].blank? && !options[:select]
options[:readonly] = true
end
end
end
def encode_quoted_value(value) #:nodoc:
quoted_value = connection.quote(value)
quoted_value = "'#{quoted_value[1..-2].gsub(/\'/, "\\\\'")}'" if quoted_value.include?("\\\'") # (for ruby mode) "
quoted_value
end
end
public
# 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.
def initialize(attributes = nil)
@attributes = attributes_from_column_definition
@attributes_cache = {}
@new_record = true
ensure_proper_type
self.attributes = attributes unless attributes.nil?
assign_attributes(self.class.send(:scope, :create)) if self.class.send(:scoped?, :create)
result = yield self if block_given?
callback(:after_initialize) if respond_to_without_attributes?(:after_initialize)
result
end
# A model instance's primary key is always available as model.id
# whether you name it the default 'id' or set it to something else.
def id
attr_name = self.class.primary_key
column = column_for_attribute(attr_name)
self.class.send(:define_read_method, :id, attr_name, column)
# now that the method exists, call it
self.send attr_name.to_sym
end
# Returns a String, which Action Pack uses for constructing an URL to this
# object. The default implementation returns this record's id as a String,
# or nil if this record's unsaved.
#
# For example, suppose that you have a User model, and that you have a
# <tt>map.resources :users</tt> route. Normally, +user_path+ will
# construct a path with the user object's 'id' in it:
#
# user = User.find_by_name('Phusion')
# user_path(user) # => "/users/1"
#
# You can override +to_param+ in your model to make +user_path+ construct
# a path using the user's name instead of the user's id:
#
# class User < ActiveRecord::Base
# def to_param # overridden
# name
# end
# end
#
# user = User.find_by_name('Phusion')
# user_path(user) # => "/users/Phusion"
def to_param
# We can't use alias_method here, because method 'id' optimizes itself on the fly.
(id = self.id) ? id.to_s : nil # Be sure to stringify the id for routes
end
# Returns a cache key that can be used to identify this record.
#
# ==== Examples
#
# Product.new.cache_key # => "products/new"
# Product.find(5).cache_key # => "products/5" (updated_at not available)
# Person.find(5).cache_key # => "people/5-20071224150000" (updated_at available)
def cache_key
case
when new_record?
"#{self.class.model_name.cache_key}/new"
when timestamp = self[:updated_at]
"#{self.class.model_name.cache_key}/#{id}-#{timestamp.to_s(:number)}"
else
"#{self.class.model_name.cache_key}/#{id}"
end
end
def id_before_type_cast #:nodoc:
read_attribute_before_type_cast(self.class.primary_key)
end
def quoted_id #:nodoc:
quote_value(id, column_for_attribute(self.class.primary_key))
end
# Sets the primary ID.
def id=(value)
write_attribute(self.class.primary_key, value)
end
# Returns true if this object hasn't been saved yet -- that is, a record for the object doesn't exist yet; otherwise, returns false.
def new_record?
@new_record || false
end
# :call-seq:
# save(perform_validation = true)
#
# Saves the model.
#
# If the model is new a record gets created in the database, otherwise
# the existing record gets updated.
#
# If +perform_validation+ is true validations run. If any of them fail
# the action is cancelled and +save+ returns +false+. If the flag is
# false validations are bypassed altogether. See
# ActiveRecord::Validations for more information.
#
# There's a series of callbacks associated with +save+. If any of the
# <tt>before_*</tt> callbacks return +false+ the action is cancelled and
# +save+ returns +false+. See ActiveRecord::Callbacks for further
# details.
def save
create_or_update
end
# Saves the model.
#
# If the model is new a record gets created in the database, otherwise
# the existing record gets updated.
#
# With <tt>save!</tt> validations always run. If any of them fail
# ActiveRecord::RecordInvalid gets raised. See ActiveRecord::Validations
# for more information.
#
# There's a series of callbacks associated with <tt>save!</tt>. If any of
# the <tt>before_*</tt> callbacks return +false+ the action is cancelled
# and <tt>save!</tt> raises ActiveRecord::RecordNotSaved. See
# ActiveRecord::Callbacks for further details.
def save!
create_or_update || raise(RecordNotSaved)
end
# Deletes the record in the database and freezes this instance to
# reflect that no changes should be made (since they can't be
# persisted). Returns the frozen instance.
#
# The row is simply removed with a SQL +DELETE+ statement on the
# record's primary key, and no callbacks are executed.
#
# To enforce the object's +before_destroy+ and +after_destroy+
# callbacks, Observer methods, or any <tt>:dependent</tt> association
# options, use <tt>#destroy</tt>.
def delete
self.class.delete(id) unless new_record?
@destroyed = true
freeze
end
# Deletes the record in the database and freezes this instance to reflect that no changes should
# be made (since they can't be persisted).
def destroy
unless new_record?
connection.delete(
"DELETE FROM #{self.class.quoted_table_name} " +
"WHERE #{connection.quote_column_name(self.class.primary_key)} = #{quoted_id}",
"#{self.class.name} Destroy"
)
end
@destroyed = true
freeze
end
# Returns a clone of the record that hasn't been assigned an id yet and
# is treated as a new record. Note that this is a "shallow" clone:
# it copies the object's attributes only, not its associations.
# The extent of a "deep" clone is application-specific and is therefore
# left to the application to implement according to its need.
def clone
attrs = clone_attributes(:read_attribute_before_type_cast)
attrs.delete(self.class.primary_key)
record = self.class.new
record.send :instance_variable_set, '@attributes', attrs
record
end
# Returns an instance of the specified +klass+ with the attributes of the current record. This is mostly useful in relation to
# single-table inheritance structures where you want a subclass to appear as the superclass. This can be used along with record
# identification in Action Pack to allow, say, <tt>Client < Company</tt> to do something like render <tt>:partial => @client.becomes(Company)</tt>
# to render that instance using the companies/company partial instead of clients/client.
#
# Note: The new instance will share a link to the same attributes as the original class. So any change to the attributes in either
# instance will affect the other.
def becomes(klass)
klass.new.tap do |became|
became.instance_variable_set("@attributes", @attributes)
became.instance_variable_set("@attributes_cache", @attributes_cache)
became.instance_variable_set("@new_record", new_record?)
end
end
# Updates a single attribute and saves the record without going through the normal validation procedure.
# This is especially useful for boolean flags on existing records. The regular +update_attribute+ method
# in Base is replaced with this when the validations module is mixed in, which it is by default.
def update_attribute(name, value)
send(name.to_s + '=', value)
save(false)
end
# Updates all the attributes from the passed-in Hash and saves the record. If the object is invalid, the saving will
# fail and false will be returned.
def update_attributes(attributes)
with_transaction_returning_status(:update_attributes_inside_transaction, attributes)
end
def update_attributes_inside_transaction(attributes) #:nodoc:
self.attributes = attributes
save
end
# Updates an object just like Base.update_attributes but calls save! instead of save so an exception is raised if the record is invalid.
def update_attributes!(attributes)
with_transaction_returning_status(:update_attributes_inside_transaction!, attributes)
end
def update_attributes_inside_transaction!(attributes) #:nodoc:
self.attributes = attributes
save!
end
# Initializes +attribute+ to zero if +nil+ and adds the value passed as +by+ (default is 1).
# The increment is performed directly on the underlying attribute, no setter is invoked.
# Only makes sense for number-based attributes. Returns +self+.
def increment(attribute, by = 1)
self[attribute] ||= 0
self[attribute] += by
self
end
# Wrapper around +increment+ that saves the record. This method differs from
# its non-bang version in that it passes through the attribute setter.
# Saving is not subjected to validation checks. Returns +true+ if the
# record could be saved.
def increment!(attribute, by = 1)
increment(attribute, by).update_attribute(attribute, self[attribute])
end
# Initializes +attribute+ to zero if +nil+ and subtracts the value passed as +by+ (default is 1).
# The decrement is performed directly on the underlying attribute, no setter is invoked.
# Only makes sense for number-based attributes. Returns +self+.
def decrement(attribute, by = 1)
self[attribute] ||= 0
self[attribute] -= by
self
end
# Wrapper around +decrement+ that saves the record. This method differs from
# its non-bang version in that it passes through the attribute setter.
# Saving is not subjected to validation checks. Returns +true+ if the
# record could be saved.
def decrement!(attribute, by = 1)
decrement(attribute, by).update_attribute(attribute, self[attribute])
end
# Assigns to +attribute+ the boolean opposite of <tt>attribute?</tt>. So
# if the predicate returns +true+ the attribute will become +false+. This
# method toggles directly the underlying value without calling any setter.
# Returns +self+.
def toggle(attribute)
self[attribute] = !send("#{attribute}?")
self
end
# Wrapper around +toggle+ that saves the record. This method differs from
# its non-bang version in that it passes through the attribute setter.
# Saving is not subjected to validation checks. Returns +true+ if the
# record could be saved.
def toggle!(attribute)
toggle(attribute).update_attribute(attribute, self[attribute])
end
# Reloads the attributes of this object from the database.
# The optional options argument is passed to find when reloading so you
# may do e.g. record.reload(:lock => true) to reload the same record with
# an exclusive row lock.
def reload(options = nil)
clear_aggregation_cache
clear_association_cache
@attributes.update(self.class.send(:with_exclusive_scope) { self.class.find(self.id, options) }.instance_variable_get('@attributes'))
@attributes_cache = {}
self
end
# Returns the value of the attribute identified by <tt>attr_name</tt> after it has been typecast (for example,
# "2004-12-12" in a data column is cast to a date object, like Date.new(2004, 12, 12)).
# (Alias for the protected read_attribute method).
def [](attr_name)
read_attribute(attr_name)
end
# Updates the attribute identified by <tt>attr_name</tt> with the specified +value+.
# (Alias for the protected write_attribute method).
def []=(attr_name, value)
write_attribute(attr_name, value)
end
# Allows you to set all the attributes at once by passing in a hash with keys
# matching the attribute names (which again matches the column names).
#
# If +guard_protected_attributes+ is true (the default), then sensitive
# attributes can be protected from this form of mass-assignment by using
# the +attr_protected+ macro. Or you can alternatively specify which
# attributes *can* be accessed with the +attr_accessible+ macro. Then all the
# attributes not included in that won't be allowed to be mass-assigned.
#
# class User < ActiveRecord::Base
# attr_protected :is_admin
# end
#
# user = User.new
# user.attributes = { :username => 'Phusion', :is_admin => true }
# user.username # => "Phusion"
# user.is_admin? # => false
#
# user.send(:attributes=, { :username => 'Phusion', :is_admin => true }, false)
# user.is_admin? # => true
def attributes=(new_attributes, guard_protected_attributes = true)
return if new_attributes.nil?
attributes = new_attributes.dup
attributes.stringify_keys!
attributes = remove_attributes_protected_from_mass_assignment(attributes) if guard_protected_attributes
assign_attributes(attributes) if attributes and attributes.any?
end
# Returns a hash of all the attributes with their names as keys and the values of the attributes as values.
def attributes
attrs = {}
attribute_names.each { |name| attrs[name] = read_attribute(name) }
attrs
end
# Returns a hash of attributes before typecasting and deserialization.
def attributes_before_type_cast
self.attribute_names.inject({}) do |attrs, name|
attrs[name] = read_attribute_before_type_cast(name)
attrs
end
end
# Returns an <tt>#inspect</tt>-like string for the value of the
# attribute +attr_name+. String attributes are elided after 50
# characters, and Date and Time attributes are returned in the
# <tt>:db</tt> format. Other attributes return the value of
# <tt>#inspect</tt> without modification.
#
# person = Person.create!(:name => "David Heinemeier Hansson " * 3)
#
# person.attribute_for_inspect(:name)
# # => '"David Heinemeier Hansson David Heinemeier Hansson D..."'
#
# person.attribute_for_inspect(:created_at)
# # => '"2009-01-12 04:48:57"'
def attribute_for_inspect(attr_name)
value = read_attribute(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)}")
else
value.inspect
end
end
# 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).
def attribute_present?(attribute)
value = read_attribute(attribute)
!value.blank?
end
# Returns true if the given attribute is in the attributes hash
def has_attribute?(attr_name)
@attributes.has_key?(attr_name.to_s)
end
# Returns an array of names for the attributes available on this object sorted alphabetically.
def attribute_names
@attributes.keys.sort
end
# Returns the column object for the named attribute.
def column_for_attribute(name)
self.class.columns_hash[name.to_s]
end
# Returns true if the +comparison_object+ is the same object, or is of the same type and has the same id.
def ==(comparison_object)
comparison_object.equal?(self) ||
(comparison_object.instance_of?(self.class) &&
comparison_object.id == id &&
!comparison_object.new_record?)
end
# Delegates to ==
def eql?(comparison_object)
self == (comparison_object)
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) ]
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
# Returns +true+ if the record has been destroyed.
def destroyed?
@destroyed
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?
defined?(@readonly) && @readonly == true
end
# Marks this record as read only.
def readonly!
@readonly = true
end
# Returns the contents of the record as a nicely formatted string.
def inspect
attributes_as_nice_string = self.class.column_names.collect { |name|
if has_attribute?(name) || new_record?
"#{name}: #{attribute_for_inspect(name)}"
end
}.compact.join(", ")
"#<#{self.class} #{attributes_as_nice_string}>"
end
private
# Assigns attributes, dealing nicely with both multi and single paramater attributes
# Assumes attributes is a hash
def assign_attributes(attributes={})
multiparameter_attributes = []
attributes.each do |k, v|
if k.to_s.include?("(")
multiparameter_attributes << [ k, v ]
else
respond_to?(:"#{k}=") ? send(:"#{k}=", v) : raise(UnknownAttributeError, "unknown attribute: #{k}")
end
end
assign_multiparameter_attributes(multiparameter_attributes) unless multiparameter_attributes.empty?
end
def create_or_update
raise ReadOnlyRecord if readonly?
result = new_record? ? create : update
result != false
end
# Updates the associated record with values matching those of the instance attributes.
# Returns the number of affected rows.
def update(attribute_names = @attributes.keys)
quoted_attributes = attributes_with_quotes(false, false, attribute_names)
return 0 if quoted_attributes.empty?
connection.update(
"UPDATE #{self.class.quoted_table_name} " +
"SET #{quoted_comma_pair_list(connection, quoted_attributes)} " +
"WHERE #{connection.quote_column_name(self.class.primary_key)} = #{quote_value(id)}",
"#{self.class.name} Update"
)
end
# Creates a record with values matching those of the instance attributes
# and returns its id.
def create
if self.id.nil? && connection.prefetch_primary_key?(self.class.table_name)
self.id = connection.next_sequence_value(self.class.sequence_name)
end
quoted_attributes = attributes_with_quotes
statement = if quoted_attributes.empty?
connection.empty_insert_statement(self.class.table_name)
else
"INSERT INTO #{self.class.quoted_table_name} " +
"(#{quoted_column_names.join(', ')}) " +
"VALUES(#{quoted_attributes.values.join(', ')})"
end
self.id = connection.insert(statement, "#{self.class.name} Create",
self.class.primary_key, self.id, self.class.sequence_name)
@new_record = false
id
end
# Sets the attribute used for single table inheritance to this class name if this is not the ActiveRecord::Base descendant.
# Considering the hierarchy Reply < Message < ActiveRecord::Base, this makes it possible to do Reply.new without having to
# set <tt>Reply[Reply.inheritance_column] = "Reply"</tt> yourself. No such attribute would be set for objects of the
# Message class in that example.
def ensure_proper_type
unless self.class.descends_from_active_record?
write_attribute(self.class.inheritance_column, self.class.sti_name)
end
end
def convert_number_column_value(value)
if value == false
0
elsif value == true
1
elsif value.is_a?(String) && value.blank?
nil
else
value
end
end
def remove_attributes_protected_from_mass_assignment(attributes)
safe_attributes =
if self.class.accessible_attributes.nil? && self.class.protected_attributes.nil?
attributes.reject { |key, value| attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
elsif self.class.protected_attributes.nil?
attributes.reject { |key, value| !self.class.accessible_attributes.include?(key.gsub(/\(.+/, "")) || attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
elsif self.class.accessible_attributes.nil?
attributes.reject { |key, value| self.class.protected_attributes.include?(key.gsub(/\(.+/,"")) || attributes_protected_by_default.include?(key.gsub(/\(.+/, "")) }
else
raise "Declare either attr_protected or attr_accessible for #{self.class}, but not both."
end
removed_attributes = attributes.keys - safe_attributes.keys
if removed_attributes.any?
log_protected_attribute_removal(removed_attributes)
end
safe_attributes
end
# Removes attributes which have been marked as readonly.
def remove_readonly_attributes(attributes)
unless self.class.readonly_attributes.nil?
attributes.delete_if { |key, value| self.class.readonly_attributes.include?(key.gsub(/\(.+/,"")) }
else
attributes
end
end
def log_protected_attribute_removal(*attributes)
logger.debug "WARNING: Can't mass-assign these protected attributes: #{attributes.join(', ')}"
end
# The primary key and inheritance column can never be set by mass-assignment for security reasons.
def attributes_protected_by_default
default = [ self.class.primary_key, self.class.inheritance_column ]
default << 'id' unless self.class.primary_key.eql? 'id'
default
end
# Returns a copy of the attributes hash where all the values have been safely quoted for use in
# an SQL statement.
def attributes_with_quotes(include_primary_key = true, include_readonly_attributes = true, attribute_names = @attributes.keys)
quoted = {}
connection = self.class.connection
attribute_names.each do |name|
if (column = column_for_attribute(name)) && (include_primary_key || !column.primary)
value = read_attribute(name)
# We need explicit to_yaml because quote() does not properly convert Time/Date fields to YAML.
if value && self.class.serialized_attributes.has_key?(name) && (value.acts_like?(:date) || value.acts_like?(:time))
value = value.to_yaml
end
quoted[name] = connection.quote(value, column)
end
end
include_readonly_attributes ? quoted : remove_readonly_attributes(quoted)
end
# Quote strings appropriately for SQL statements.
def quote_value(value, column = nil)
self.class.connection.quote(value, column)
end
# Interpolate custom SQL string in instance context.
# Optional record argument is meant for custom insert_sql.
def interpolate_sql(sql, record = nil)
instance_eval("%@#{sql.gsub('@', '\@')}@")
end
# Initializes the attributes array with keys matching the columns from the linked table and
# the values matching the corresponding default value of that column, so
# that a new instance, or one populated from a passed-in Hash, still has all the attributes
# that instances loaded from the database would.
def attributes_from_column_definition
self.class.columns.inject({}) do |attributes, column|
attributes[column.name] = column.default unless column.name == self.class.primary_key
attributes
end
end
# Instantiates objects for all attribute classes that needs more than one constructor parameter. This is done
# by calling new on the column type or aggregation type (through composed_of) object with these parameters.
# So having the pairs written_on(1) = "2004", written_on(2) = "6", written_on(3) = "24", will instantiate
# written_on (a date type) with Date.new("2004", "6", "24"). You can also specify a typecast character in the
# parentheses to have the parameters typecasted before they're used in the constructor. Use i for Fixnum, f for Float,
# s for String, and a for Array. If all the values for a given attribute are empty, the attribute will be set to nil.
def assign_multiparameter_attributes(pairs)
execute_callstack_for_multiparameter_attributes(
extract_callstack_for_multiparameter_attributes(pairs)
)
end
def instantiate_time_object(name, values)
if self.class.send(:create_time_zone_conversion_attribute?, name, column_for_attribute(name))
Time.zone.local(*values)
else
Time.time_with_datetime_fallback(@@default_timezone, *values)
end
end
def execute_callstack_for_multiparameter_attributes(callstack)
errors = []
callstack.each do |name, values_with_empty_parameters|
begin
klass = (self.class.reflect_on_aggregation(name.to_sym) || column_for_attribute(name)).klass
# in order to allow a date to be set without a year, we must keep the empty values.
# Otherwise, we wouldn't be able to distinguish it from a date with an empty day.
values = values_with_empty_parameters.reject(&:nil?)
if values.empty?
send(name + "=", nil)
else
value = if Time == klass
instantiate_time_object(name, values)
elsif Date == klass
begin
values = values_with_empty_parameters.collect do |v| v.nil? ? 1 : v end
Date.new(*values)
rescue ArgumentError => ex # if Date.new raises an exception on an invalid date
instantiate_time_object(name, values).to_date # we instantiate Time object and convert it back to a date thus using Time's logic in handling invalid dates
end
else
klass.new(*values)
end
send(name + "=", value)
end
rescue => ex
errors << AttributeAssignmentError.new("error on assignment #{values.inspect} to #{name}", ex, name)
end
end
unless errors.empty?
raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes"
end
end
def extract_callstack_for_multiparameter_attributes(pairs)
attributes = { }
for pair in pairs
multiparameter_name, value = pair
attribute_name = multiparameter_name.split("(").first
attributes[attribute_name] = [] unless attributes.include?(attribute_name)
parameter_value = value.empty? ? nil : type_cast_attribute_value(multiparameter_name, value)
attributes[attribute_name] << [ find_parameter_position(multiparameter_name), parameter_value ]
end
attributes.each { |name, values| attributes[name] = values.sort_by{ |v| v.first }.collect { |v| v.last } }
end
def type_cast_attribute_value(multiparameter_name, value)
multiparameter_name =~ /\([0-9]*([if])\)/ ? value.send("to_" + $1) : value
end
def find_parameter_position(multiparameter_name)
multiparameter_name.scan(/\(([0-9]*).*\)/).first.first
end
# Returns a comma-separated pair list, like "key1 = val1, key2 = val2".
def comma_pair_list(hash)
hash.map { |k,v| "#{k} = #{v}" }.join(", ")
end
def quoted_column_names(attributes = attributes_with_quotes)
connection = self.class.connection
attributes.keys.collect do |column_name|
connection.quote_column_name(column_name)
end
end
def self.quoted_table_name
self.connection.quote_table_name(self.table_name)
end
def quote_columns(quoter, hash)
hash.inject({}) do |quoted, (name, value)|
quoted[quoter.quote_column_name(name)] = value
quoted
end
end
def quoted_comma_pair_list(quoter, hash)
comma_pair_list(quote_columns(quoter, hash))
end
def object_from_yaml(string)
return string unless string.is_a?(String) && string =~ /^---/
YAML::load(string) rescue string
end
def clone_attributes(reader_method = :read_attribute, attributes = {})
self.attribute_names.inject(attributes) do |attrs, name|
attrs[name] = clone_attribute_value(reader_method, name)
attrs
end
end
def clone_attribute_value(reader_method, attribute_name)
value = send(reader_method, attribute_name)
value.duplicable? ? value.clone : value
rescue TypeError, NoMethodError
value
end
end
Base.class_eval do
extend QueryCache::ClassMethods
include Validations
include Locking::Optimistic, Locking::Pessimistic
include AttributeMethods
include Dirty
include Callbacks, Observing, Timestamp
include Associations, AssociationPreload, NamedScope
# AutosaveAssociation needs to be included before Transactions, because we want
# #save_with_autosave_associations to be wrapped inside a transaction.
include AutosaveAssociation, NestedAttributes
include Aggregations, Transactions, Reflection, Batches, Calculations, Serialization
end
end
# TODO: Remove this and make it work with LAZY flag
require 'active_record/connection_adapters/abstract_adapter'
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