require 'yaml' require 'set' module ActiveRecord #:nodoc: # Generic ActiveRecord exception class. class ActiveRecordError < StandardError end # Raised when the single-table inheritance mechanism failes 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 config/database.yml misses adapter field). class AdapterNotSpecified < ActiveRecordError end # Raised when ActiveRecord cannot find database adapter specified in config/database.yml or programmatically. class AdapterNotFound < ActiveRecordError end # Raised when connection to the database could not been established (for example when connection= is given a nil object). class ConnectionNotEstablished < ActiveRecordError end # Raised when ActiveRecord 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 :condition 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 # Used by ActiveRecord transaction mechanism to distinguish rollback from other exceptional situations. # You can use it to roll your transaction back explicitly in the block passed to +transaction+ method. class Rollback < ActiveRecordError end # Raised when attribute has a name reserved by ActiveRecord (when attribute has name of one of ActiveRecord 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 :select has been specified. class MissingAttributeError < NoMethodError end # Raised when an error occured while doing a mass assignment to an attribute through the # attributes= 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 authenticate_unsafely method inserts the parameters directly into the query and is thus susceptible to SQL-injection # attacks if the user_name and +password+ parameters come directly from an HTTP request. The authenticate_safely and # authenticate_safely_simply both will sanitize the user_name 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 read_attribute(attr_name) and write_attribute(attr_name, value) 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 self[:attribute]=(value) and self[:attribute] instead of write_attribute(:attribute, value) and # read_attribute(:attribute) 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 name attribute has a name? 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 _before_type_cast accessors that all attributes have. For example, if your Account model # has a balance attribute, you can call account.balance_before_type_cast or account.id_before_type_cast. # # 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 find_by_ or find_all_by_, so you get finders like Person.find_by_user_name, # Person.find_all_by_last_name, Payment.find_by_transaction_id. So instead of writing # Person.find(:first, :conditions => ["user_name = ?", user_name]), you just do Person.find_by_user_name(user_name). # And instead of writing Person.find(:all, :conditions => ["last_name = ?", last_name]), you just do Person.find_all_by_last_name(last_name). # # It's also possible to use multiple attributes in the same find by separating them with "_and_", so you get finders like # Person.find_by_user_name_and_password or even Payment.find_by_purchaser_and_state_and_country. So instead of writing # Person.find(:first, :conditions => ["user_name = ? AND password = ?", user_name, password]), you just do # Person.find_by_user_name_and_password(user_name, password). # # It's even possible to use all the additional parameters to find. For example, the full interface for Payment.find_all_by_amount # is actually Payment.find_all_by_amount(amount, options). And the full interface to Person.find_by_user_name is # actually Person.find_by_user_name(user_name, options). So you could call Payment.find_all_by_amount(50, :order => "created_on"). # # The same dynamic finder style can be used to create the object if it doesn't already exist. This dynamic finder is called with # find_or_create_by_ 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 find_or_initialize_by_ finder if you want to return a new record without saving it first. Protected attributes won't be setted 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 # descendent 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 Base.inheritance_column). 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 Firm.create(:name => "37signals"), this record will be saved in the companies table with type = "Firm". You can then # fetch this row again using Company.find(:first, "name = '37signals'") 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 Course.establish_connection # and Course *and all 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 establish_connection didn't include an # :adapter key. # * AdapterNotFound - The :adapter key used in establish_connection 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 establish_connection 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 # attributes= 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 attributes= 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 Base.logger= which will then be used by all # instances in the current object space. class Base # 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 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 = {} cattr_accessor :configurations, :instance_writer => false @@configurations = {} # 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 # 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. cattr_accessor :table_name_prefix, :instance_writer => false @@table_name_prefix = "" # 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 = "" # 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 # 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 # 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 # Determines whether to use a connection for each thread, or a single shared connection for all threads. # Defaults to false. If you're writing a threaded application, set to true # and periodically call verify_active_connections! to clear out connections # assigned to stale threads. cattr_accessor :allow_concurrency, :instance_writer => false @@allow_concurrency = false # 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 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. # * 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. # * Find all: This will return all the records matched by the options used. If no records are found, an empty array is returned. # # All approaches accept an options hash as their last parameter. The options are: # # * :conditions: An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro. # * :order: An SQL fragment like "created_at DESC, name". # * :group: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. # * :limit: An integer determining the limit on the number of rows that should be returned. # * :offset: An integer determining the offset from where the rows should be fetched. So at 5, it would skip rows 0 through 4. # * :joins: Either an SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id" (rarely needed) # or named associations in the same form used for the :include option, which will perform an INNER JOIN on the associated table(s). # 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 :readonly => false to override. # * :include: Names associations that should be loaded alongside using LEFT OUTER JOINs. The symbols named refer # to already defined associations. See eager loading under Associations. # * :select: 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. # * :from: 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). # * :readonly: Mark the returned records read-only so they cannot be saved or updated. # * :lock: An SQL fragment like "FOR UPDATE" or "LOCK IN SHARE MODE". # :lock => true gives connection's default exclusive lock, usually "FOR UPDATE". # # Examples for 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 :order # to ensure the results are sorted. # # Examples for 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, :order => "created_on DESC", :offset => 5) # # Examples for 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) # # Examples for 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 person.visits == 2, add 1 to it, and save, resulting # in two saves of person.visits = 3. By locking the row, the second # transaction has to wait until the first is finished; we get the # expected person.visits == 4. # 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 # This is an alias for find(:first). You can pass in all the same arguments to this method as you can # to find(:first) def first(*args) find(:first, *args) end # This is an alias for find(:last). You can pass in all the same arguments to this method as you can # to find(:last) 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 +Product.find_by_sql+ 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" # > [#"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] # > [#"The Cheap Man Buys Twice"}>, ...] def find_by_sql(sql) connection.select_all(sanitize_sql(sql), "#{name} Load").collect! { |record| instantiate(record) } end # Checks whether a record exists in the database that matches conditions given. These conditions # can either be a single integer representing a primary key id to be found, or a condition to be # matched like using ActiveRecord#find. # # The +id_or_conditions+ parameter can be an Integer or a String if you want to search the primary key # column of the table for a matching id, or if you're looking to match against a condition you can use # an Array or a Hash. # # Possible gotcha: You can't pass in a condition as a string e.g. "name = 'Jamie'", this would be # sanitized and then queried against the primary key column as "id = 'name = \'Jamie" # # ==== Examples # Person.exists?(5) # Person.exists?('5') # Person.exists?(:name => "David") # Person.exists?(['name LIKE ?', "%#{query}%"]) def exists?(id_or_conditions) connection.select_all( construct_finder_sql( :select => "#{quoted_table_name}.#{primary_key}", :conditions => expand_id_conditions(id_or_conditions), :limit => 1 ), "#{name} Exists" ).size > 0 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. # # ==== Attributes # # * +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 # Delete an object (or multiple objects) where the +id+ given matches the primary_key. A SQL +DELETE+ command # is executed on the database which means that no callbacks are fired off running this. This is an efficient method # of deleting records that don't need cleaning up after or other actions to be taken. # # Objects are _not_ instantiated with this method. # # ==== Attributes # # * +id+ - Can be either an Integer or an Array of Integers. # # ==== Examples # # # Delete a single object # Todo.delete(1) # # # Delete multiple objects # todos = [1,2,3] # Todo.delete(todos) 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. # # ==== Attributes # # * +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. # # ==== Attributes # # * +updates+ - A String of column and value pairs that will be set on any records that match conditions. # * +conditions+ - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. # See conditions in the intro for more info. # * +options+ - Additional options are :limit and/or :order, 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) add_conditions!(sql, conditions, scope) add_order!(sql, options[:order], nil) add_limit!(sql, options, nil) connection.update(sql, "#{name} Update") end # Destroys the records matching +conditions+ by instantiating each record and calling the destroy method. # This means at least 2*N database queries to destroy N records, so avoid destroy_all if you are deleting # many records. If you want to simply delete records without worrying about dependent associations or # callbacks, use the much faster +delete_all+ method instead. # # ==== Attributes # # * +conditions+ - Conditions are specified the same way as with +find+ method. # # ==== Example # # Person.destroy_all "last_login < '2004-04-04'" # # This loads and destroys each person one by one, including its dependent associations and before_ and # after_destroy callbacks. 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 and invoking callbacks. This is a single SQL query, much more efficient # than destroy_all. # # ==== Attributes # # * +conditions+ - Conditions are specified the same way as with +find+ method. # # ==== Example # # Post.delete_all "person_id = 5 AND (category = 'Something' OR category = 'Else')" # # This deletes the affected posts all at once with a single DELETE query. If you need to destroy dependent # associations or call your before_ 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. # # ==== Attributes # # * +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 # 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: # # ==== Attributes # # * +id+ - The id of the object you wish to update a counter on. # * +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 def update_counters(id, counters) updates = counters.inject([]) { |list, (counter_name, increment)| sign = increment < 0 ? "-" : "+" list << "#{connection.quote_column_name(counter_name)} = #{connection.quote_column_name(counter_name)} #{sign} #{increment.abs}" }.join(", ") update_all(updates, "#{connection.quote_column_name(primary_key)} = #{quote_value(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. # # ==== Attributes # # * +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. # # ==== Attributes # # * +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 new(attributes) and # attributes=(attributes). Their assignment will simply be ignored. Instead, you can use the direct writer # methods to do assignment. This is meant to protect sensitive attributes from being overwritten by URL/form hackers. Example: # # 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 # Similar to the attr_protected macro, this protects attributes of your model from mass-assignment, # such as new(attributes) and attributes=(attributes) # however, it does it in the opposite way. This locks all attributes and only allows access to the # attributes specified. Assignment to attributes not in this list will be ignored and need to be set # using the direct writer methods instead. This is meant to protect sensitive attributes from being # overwritten by URL/form hackers. If you'd rather start from an all-open default and restrict # attributes as needed, have a look at attr_protected. # # ==== Attributes # # * *attributes A comma separated list of symbols that represent columns _not_ to be protected # # ==== Examples # # 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. # # ==== Attributes # # * +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. So if the hierarchy looks like: Reply < Message < ActiveRecord, 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 = "#{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 = Inflector.foreign_key(base_name, false) when :table_name_with_underscore key = Inflector.foreign_key(base_name) end key 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. # # Example: # # 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. # # Example: # # 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. # # Example: # # 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. # # Example: # # 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: # 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. 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 # 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" # Deprecated in favor of just calling "first_name".humanize def human_attribute_name(attribute_key_name) #:nodoc: attribute_key_name.humanize 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 connection.quote. 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 log_level, # 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 use_silence is set to false. def benchmark(title, log_level = Logger::DEBUG, use_silence = true) if logger && logger.level <= log_level result = nil seconds = Benchmark.realtime { result = use_silence ? silence { yield } : yield } logger.add(log_level, "#{title} (#{'%.5f' % seconds})") 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 #abstract_class?). 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 = matches_dynamic_finder?(method_id) || matches_dynamic_finder_with_initialize_or_create?(method_id) return true if all_attributes_exists?(extract_attribute_names_from_match(match)) end super 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) scoped_order = reverse_sql_order(scope(:find, :order)) scoped_methods.select { |s| s[:find].update(:order => scoped_order) } end find_initial(options.merge({ :order => order })) end def reverse_sql_order(order_query) reversed_query = order_query.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) (/^::/ =~ type_name) ? type_name : "#{parent.name}::#{type_name}" end def construct_finder_sql(options) scope = scope(:find) sql = "SELECT #{(scope && scope[:select]) || options[:select] || (options[:joins] && quoted_table_name + '.*') || '*'} " sql << "FROM #{(scope && scope[:from]) || options[:from] || quoted_table_name} " add_joins!(sql, options, scope) add_conditions!(sql, options[:conditions], scope) add_group!(sql, options[:group], 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 # 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 # 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 add_order!(sql, order, scope = :auto) scope = scope(:find) if :auto == scope scoped_order = scope[:order] if scope if order sql << " ORDER BY #{order}" sql << ", #{scoped_order}" if scoped_order else sql << " ORDER BY #{scoped_order}" if scoped_order end end def add_group!(sql, group, scope = :auto) if group sql << " GROUP BY #{group}" else scope = scope(:find) if :auto == scope if scope && (scoped_group = scope[:group]) sql << " GROUP BY #{scoped_group}" end end end # The optional scope argument is for the current :find 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 :find scope. # The :lock option has precedence over a scoped :lock. 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 :find scope. def add_joins!(sql, options, scope = :auto) scope = scope(:find) if :auto == scope [(scope && scope[:joins]), options[:joins]].each do |join| case join when Symbol, Hash, Array join_dependency = ActiveRecord::Associations::ClassMethods::InnerJoinDependency.new(self, join, nil) sql << " #{join_dependency.join_associations.collect { |assoc| assoc.association_join }.join} " else sql << " #{join} " end 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 :find 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 quoted_inheritance_column = connection.quote_column_name(inheritance_column) type_condition = subclasses.inject("#{quoted_table_name}.#{quoted_inheritance_column} = '#{name.demodulize}' ") do |condition, subclass| condition << "OR #{quoted_table_name}.#{quoted_inheritance_column} = '#{subclass.name.demodulize}' " 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 = Inflector.underscore(Inflector.demodulize(class_name)) table_name = Inflector.pluralize(table_name) if pluralize_table_names table_name end # Enables dynamic finders like find_by_user_name(user_name) and find_by_user_name_and_password(user_name, password) that are turned into # find(:first, :conditions => ["user_name = ?", user_name]) and find(:first, :conditions => ["user_name = ? AND password = ?", user_name, password]) # respectively. Also works for find(:all) by using find_all_by_amount(50) that is turned into find(:all, :conditions => ["amount = ?", 50]). # # It's even possible to use all the additional parameters to find. For example, the full interface for find_all_by_amount # is actually find_all_by_amount(amount, options). # # This also enables you to initialize a record if it is not found, such as find_or_initialize_by_amount(amount) # or find_or_create_by_user_and_password(user, password). # # Each dynamic finder 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) if match = matches_dynamic_finder?(method_id) finder = determine_finder(match) attribute_names = extract_attribute_names_from_match(match) super unless all_attributes_exists?(attribute_names) self.class_eval %{ 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) if options[:conditions] with_scope(:find => finder_options) do ActiveSupport::Deprecation.silence { send(:#{finder}, options) } end else ActiveSupport::Deprecation.silence { send(:#{finder}, options.merge(finder_options)) } end end }, __FILE__, __LINE__ send(method_id, *arguments) elsif match = matches_dynamic_finder_with_initialize_or_create?(method_id) instantiator = determine_instantiator(match) attribute_names = extract_attribute_names_from_match(match) super unless all_attributes_exists?(attribute_names) self.class_eval %{ def self.#{method_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(*[:#{attribute_names.join(',:')}]) else find_attributes = attributes = construct_attributes_from_arguments([:#{attribute_names.join(',:')}], args) end options = { :conditions => find_attributes } set_readonly_option!(options) record = find_initial(options) if record.nil? record = self.new { |r| r.send(:attributes=, attributes, guard_protected_attributes) } #{'yield(record) if block_given?'} #{'record.save' if instantiator == :create} record else record end end }, __FILE__, __LINE__ send(method_id, *arguments) else super end end def matches_dynamic_finder?(method_id) /^find_(all_by|by)_([_a-zA-Z]\w*)$/.match(method_id.to_s) end def matches_dynamic_finder_with_initialize_or_create?(method_id) /^find_or_(initialize|create)_by_([_a-zA-Z]\w*)$/.match(method_id.to_s) end def determine_finder(match) match.captures.first == 'all_by' ? :find_every : :find_initial end def determine_instantiator(match) match.captures.first == 'initialize' ? :new : :create end def extract_attribute_names_from_match(match) match.captures.last.split('_and_') 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(argument) case argument when nil then "IS ?" when Array, ActiveRecord::Associations::AssociationCollection then "IN (?)" when Range then "BETWEEN ? AND ?" else "= ?" 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 :find or :create. :find parameters may include the :conditions, :joins, # :include, :offset, :limit, and :readonly options. :create 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 # :conditions and :include options in :find, which are merged. # # 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 with_exclusive_scope 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 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 action == :merge && 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 hash[method][key] = merge_conditions(params[key], hash[method][key]) elsif key == :include && merge hash[method][key] = merge_includes(hash[method][key], params[key]).uniq else hash[method][key] = hash[method][key] || params[key] end end else hash[method] = params.merge(hash[method]) 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 # 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.has_key?(key) 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 thread_safe_scoped_methods #:nodoc: scoped_methods = (Thread.current[:scoped_methods] ||= {}) scoped_methods[self] ||= [] end def single_threaded_scoped_methods #:nodoc: @scoped_methods ||= [] end # pick up the correct scoped_methods version from @@allow_concurrency if @@allow_concurrency alias_method :scoped_methods, :thread_safe_scoped_methods else alias_method :scoped_methods, :single_threaded_scoped_methods 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 descendents of # MyApp::Business::Account would appear as MyApp::Business::AccountSubclass. def compute_type(type_name) modularized_name = type_name_with_module(type_name) begin class_eval(modularized_name, __FILE__, __LINE__) rescue NameError class_eval(type_name, __FILE__, __LINE__) end end # Returns the class descending directly from ActiveRecord 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 ActiveRecord 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) return nil if condition.blank? case condition when Array; sanitize_sql_array(condition) when Hash; sanitize_sql_hash_for_conditions(condition) 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" # 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) attrs = expand_hash_conditions_for_aggregates(attrs) conditions = attrs.map do |attr, value| attr = attr.to_s # Extract table name from qualified attribute names. if attr.include?('.') table_name, attr = attr.split('.', 2) table_name = connection.quote_table_name(table_name) else table_name = quoted_table_name end "#{table_name}.#{connection.quote_column_name(attr)} #{attribute_condition(value)}" 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 match = $1.to_sym if bind_vars.include?(match) 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: bind_vars.sum do |var| if var.is_a?(Range) [var.first, var.last] else [var] end end end def quote_bound_value(value) #:nodoc: if value.respond_to?(:map) && !value.is_a?(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, :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? self.class.send(:scope, :create).each { |att,value| self.send("#{att}=", value) } 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 # Enables Active Record objects to be used as URL parameters in Action Pack automatically. 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.name.tableize}/new" when self[:updated_at] "#{self.class.name.tableize}/#{id}-#{updated_at.to_s(:number)}" else "#{self.class.name.tableize}/#{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. def new_record? defined?(@new_record) && @new_record end # * No record exists: Creates a new record with values matching those of the object attributes. # * A record does exist: Updates the record with values matching those of the object attributes. # # Note: If your model specifies any validations then the method declaration dynamically # changes to: # save(perform_validation=true) # Calling save(false) saves the model without running validations. # See ActiveRecord::Validations for more information. def save create_or_update end # Attempts to save the record, but instead of just returning false if it couldn't happen, it raises a # RecordNotSaved exception 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). def destroy unless new_record? connection.delete <<-end_sql, "#{self.class.name} Destroy" DELETE FROM #{self.class.quoted_table_name} WHERE #{connection.quote_column_name(self.class.primary_key)} = #{quoted_id} end_sql end 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, Client < Company to do something like render :partial => @client.becomes(Company) # 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) returning klass.new 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. This is especially useful for boolean flags on existing records. # Note: This method is overwritten by the Validation module that'll make sure that updates made with this method # aren't subjected to validation checks. Hence, attributes can be updated even if the full object isn't valid. def update_attribute(name, value) send(name.to_s + '=', value) save 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) 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) 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 attribute?. 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.find(self.id, options).instance_variable_get('@attributes')) @attributes_cache = {} self end # Returns the value of the attribute identified by attr_name 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 attr_name 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). 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. def attributes=(new_attributes, guard_protected_attributes = true) return if new_attributes.nil? attributes = new_attributes.dup attributes.stringify_keys! multi_parameter_attributes = [] attributes = remove_attributes_protected_from_mass_assignment(attributes) if guard_protected_attributes attributes.each do |k, v| k.include?("(") ? multi_parameter_attributes << [ k, v ] : send(k + "=", v) end assign_multiparameter_attributes(multi_parameter_attributes) end # Returns a hash of all the attributes with their names as keys and the values of the attributes as values. def attributes self.attribute_names.inject({}) do |attrs, name| attrs[name] = read_attribute(name) attrs end 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 # Format attributes nicely for inspect. 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 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 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 descendent. # Considering the hierarchy Reply < Message < ActiveRecord, this makes it possible to do Reply.new without having to # set Reply[Reply.inheritance_column] = "Reply" 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, Inflector.demodulize(self.class.name)) end end def convert_number_column_value(value) case value when FalseClass; 0 when TrueClass; 1 when ''; 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? logger.debug "WARNING: Can't mass-assign these protected attributes: #{removed_attributes.join(', ')}" 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 # 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) quoted[name] = connection.quote(read_attribute(name), column) unless !include_primary_key && column.primary 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.time_zone_aware_attributes && !self.class.skip_time_zone_conversion_for_attributes.include?(name.to_sym) 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| klass = (self.class.reflect_on_aggregation(name.to_sym) || column_for_attribute(name)).klass if values.empty? send(name + "=", nil) else begin value = if Time == klass instantiate_time_object(name, values) elsif Date == klass begin 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) rescue => ex errors << AttributeAssignmentError.new("error on assignment #{values.inspect} to #{name}", ex, name) end 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) unless value.empty? attributes[attribute_name] << [ find_parameter_position(multiparameter_name), type_cast_attribute_value(multiparameter_name, value) ] end 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 =~ /$[0-9]*([a-z])$/ ? 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.inject([]) { |list, pair| list << "#{pair.first} = #{pair.last}" }.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) 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 end