diff options
Diffstat (limited to 'activerecord/lib/active_record/persistence.rb')
| -rw-r--r-- | activerecord/lib/active_record/persistence.rb | 287 |
1 files changed, 226 insertions, 61 deletions
diff --git a/activerecord/lib/active_record/persistence.rb b/activerecord/lib/active_record/persistence.rb index fd7466dfaf..8404119631 100644 --- a/activerecord/lib/active_record/persistence.rb +++ b/activerecord/lib/active_record/persistence.rb @@ -1,3 +1,5 @@ +# frozen_string_literal: true + module ActiveRecord # = Active Record \Persistence module Persistence @@ -65,11 +67,151 @@ module ActiveRecord # how this "single-table" inheritance mapping is implemented. def instantiate(attributes, column_types = {}, &block) klass = discriminate_class_for_record(attributes) - attributes = klass.attributes_builder.build_from_database(attributes, column_types) - klass.allocate.init_with("attributes" => attributes, "new_record" => false, &block) + instantiate_instance_of(klass, attributes, column_types, &block) + end + + # Updates an object (or multiple objects) and saves it to the database, if validations pass. + # The resulting object is returned whether the object was saved successfully to the database or not. + # + # ==== Parameters + # + # * +id+ - This should be the id or an array of ids to be updated. + # * +attributes+ - This should be a hash of attributes or an array of hashes. + # + # ==== Examples + # + # # Updates one record + # Person.update(15, user_name: "Samuel", group: "expert") + # + # # Updates multiple records + # people = { 1 => { "first_name" => "David" }, 2 => { "first_name" => "Jeremy" } } + # Person.update(people.keys, people.values) + # + # # Updates multiple records from the result of a relation + # people = Person.where(group: "expert") + # people.update(group: "masters") + # + # Note: Updating a large number of records will run an UPDATE + # query for each record, which may cause a performance issue. + # When running callbacks is not needed for each record update, + # it is preferred to use {update_all}[rdoc-ref:Relation#update_all] + # for updating all records in a single query. + def update(id, attributes) + if id.is_a?(Array) + id.map { |one_id| find(one_id) }.each_with_index { |object, idx| + object.update(attributes[idx]) + } + else + if ActiveRecord::Base === id + raise ArgumentError, + "You are passing an instance of ActiveRecord::Base to `update`. " \ + "Please pass the id of the object by calling `.id`." + end + object = find(id) + object.update(attributes) + object + end + 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 #delete but allows cleanup methods and other actions to be run. + # + # This essentially finds the object (or multiple objects) with the given id, creates a new object + # from the attributes, and then calls destroy on it. + # + # ==== Parameters + # + # * +id+ - This should be the id or an array of ids to be destroyed. + # + # ==== 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) + find(id).each(&:destroy) + else + find(id).destroy + end + end + + # Deletes the row with a primary key matching the +id+ argument, using a + # SQL +DELETE+ statement, and returns the number of rows deleted. Active + # Record objects are not instantiated, so the object's callbacks are not + # executed, including any <tt>:dependent</tt> association options. + # + # You can delete multiple rows at once by passing an Array of <tt>id</tt>s. + # + # Note: Although it is often much faster than the alternative, #destroy, + # skipping callbacks might bypass business logic in your application + # that ensures referential integrity or performs other essential jobs. + # + # ==== Examples + # + # # Delete a single row + # Todo.delete(1) + # + # # Delete multiple rows + # Todo.delete([2,3,4]) + def delete(id_or_array) + where(primary_key => id_or_array).delete_all + end + + def _insert_record(values) # :nodoc: + primary_key_value = nil + + if primary_key && Hash === values + primary_key_value = values[primary_key] + + if !primary_key_value && prefetch_primary_key? + primary_key_value = next_sequence_value + values[primary_key] = primary_key_value + end + end + + if values.empty? + im = arel_table.compile_insert(connection.empty_insert_statement_value(primary_key)) + im.into arel_table + else + im = arel_table.compile_insert(_substitute_values(values)) + end + + connection.insert(im, "#{self} Create", primary_key || false, primary_key_value) + end + + def _update_record(values, constraints) # :nodoc: + constraints = _substitute_values(constraints).map { |attr, bind| attr.eq(bind) } + + um = arel_table.where( + constraints.reduce(&:and) + ).compile_update(_substitute_values(values), primary_key) + + connection.update(um, "#{self} Update") + end + + def _delete_record(constraints) # :nodoc: + constraints = _substitute_values(constraints).map { |attr, bind| attr.eq(bind) } + + dm = Arel::DeleteManager.new + dm.from(arel_table) + dm.wheres = constraints + + connection.delete(dm, "#{self} Destroy") end private + # Given a class, an attributes hash, +instantiate_instance_of+ returns a + # new instance of the class. Accepts only keys as strings. + def instantiate_instance_of(klass, attributes, column_types = {}, &block) + attributes = klass.attributes_builder.build_from_database(attributes, column_types) + klass.allocate.init_from_db(attributes, &block) + end + # Called by +instantiate+ to decide which class to use for a new # record instance. # @@ -78,6 +220,14 @@ module ActiveRecord def discriminate_class_for_record(record) self end + + def _substitute_values(values) + values.map do |name, value| + attr = arel_attribute(name) + bind = predicate_builder.build_bind_attribute(name, value) + [attr, bind] + end + end end # Returns true if this object hasn't been saved yet -- that is, a record @@ -100,6 +250,10 @@ module ActiveRecord !(@new_record || @destroyed) end + ## + # :call-seq: + # save(*args) + # # Saves the model. # # If the model is new, a record gets created in the database, otherwise @@ -121,12 +275,16 @@ module ActiveRecord # # Attributes marked as readonly are silently ignored if the record is # being updated. - def save(*args) - create_or_update(*args) + def save(*args, &block) + create_or_update(*args, &block) rescue ActiveRecord::RecordInvalid false end + ## + # :call-seq: + # save!(*args) + # # Saves the model. # # If the model is new, a record gets created in the database, otherwise @@ -150,8 +308,8 @@ module ActiveRecord # being updated. # # Unless an error is raised, returns true. - def save!(*args) - create_or_update(*args) || raise(RecordNotSaved.new("Failed to save the record", self)) + def save!(*args, &block) + create_or_update(*args, &block) || raise(RecordNotSaved.new("Failed to save the record", self)) end # Deletes the record in the database and freezes this instance to @@ -167,7 +325,7 @@ module ActiveRecord # callbacks or any <tt>:dependent</tt> association # options, use <tt>#destroy</tt>. def delete - self.class.delete(id) if persisted? + _delete_row if persisted? @destroyed = true freeze end @@ -216,9 +374,10 @@ module ActiveRecord # Any change to the attributes on either instance will affect both instances. # If you want to change the sti column as well, use #becomes! instead. def becomes(klass) - became = klass.new + became = klass.allocate + became.send(:initialize) became.instance_variable_set("@attributes", @attributes) - became.instance_variable_set("@mutation_tracker", @mutation_tracker) if defined?(@mutation_tracker) + became.instance_variable_set("@mutations_from_database", @mutations_from_database ||= nil) became.instance_variable_set("@changed_attributes", attributes_changed_by_setter) became.instance_variable_set("@new_record", new_record?) became.instance_variable_set("@destroyed", destroyed?) @@ -259,11 +418,7 @@ module ActiveRecord verify_readonly_attribute(name) public_send("#{name}=", value) - if has_changes_to_save? - save(validate: false) - else - true - end + save(validate: false) end # Updates the attributes of the model from the passed-in hash and saves the @@ -279,6 +434,7 @@ module ActiveRecord end alias update_attributes update + deprecate :update_attributes # Updates its receiver just like #update but calls #save! instead # of +save+, so an exception is raised if the record is invalid and saving will fail. @@ -292,6 +448,7 @@ module ActiveRecord end alias update_attributes! update! + deprecate :update_attributes! # Equivalent to <code>update_columns(name => value)</code>. def update_column(name, value) @@ -322,13 +479,16 @@ module ActiveRecord verify_readonly_attribute(key.to_s) end - updated_count = self.class.unscoped.where(self.class.primary_key => id).update_all(attributes) + affected_rows = self.class._update_record( + attributes, + self.class.primary_key => id_in_database + ) attributes.each do |k, v| - raw_write_attribute(k, v) + write_attribute_without_type_cast(k, v) end - updated_count == 1 + affected_rows == 1 end # Initializes +attribute+ to zero if +nil+ and adds the value passed as +by+ (default is 1). @@ -343,7 +503,7 @@ module ActiveRecord # Wrapper around #increment that writes the update to the database. # Only +attribute+ is updated; the record itself is not saved. # This means that any other modified attributes will still be dirty. - # Validations and callbacks are skipped. Supports the `touch` option from + # Validations and callbacks are skipped. Supports the +touch+ option from # +update_counters+, see that for more. # Returns +self+. def increment!(attribute, by = 1, touch: nil) @@ -364,7 +524,7 @@ module ActiveRecord # Wrapper around #decrement that writes the update to the database. # Only +attribute+ is updated; the record itself is not saved. # This means that any other modified attributes will still be dirty. - # Validations and callbacks are skipped. Supports the `touch` option from + # Validations and callbacks are skipped. Supports the +touch+ option from # +update_counters+, see that for more. # Returns +self+. def decrement!(attribute, by = 1, touch: nil) @@ -501,36 +661,12 @@ module ActiveRecord MSG end - time ||= current_time_from_proper_timezone - attributes = timestamp_attributes_for_update_in_model - attributes.concat(names) - - unless attributes.empty? - changes = {} - - attributes.each do |column| - column = column.to_s - changes[column] = write_attribute(column, time) - end - - primary_key = self.class.primary_key - scope = self.class.unscoped.where(primary_key => _read_attribute(primary_key)) - - if locking_enabled? - locking_column = self.class.locking_column - scope = scope.where(locking_column => _read_attribute(locking_column)) - changes[locking_column] = increment_lock - end - - clear_attribute_changes(changes.keys) - result = scope.update_all(changes) == 1 + attribute_names = timestamp_attributes_for_update_in_model + attribute_names |= names.map(&:to_s) - if !result && locking_enabled? - raise ActiveRecord::StaleObjectError.new(self, "touch") - end - - @_trigger_update_callback = result - result + unless attribute_names.empty? + affected_rows = _touch_row(attribute_names, time) + @_trigger_update_callback = affected_rows == 1 else true end @@ -543,42 +679,71 @@ module ActiveRecord end def destroy_row - relation_for_destroy.delete_all + _delete_row end - def relation_for_destroy - self.class.unscoped.where(self.class.primary_key => id) + def _delete_row + self.class._delete_record(self.class.primary_key => id_in_database) end - def create_or_update(*args) + def _touch_row(attribute_names, time) + time ||= current_time_from_proper_timezone + + attribute_names.each do |attr_name| + write_attribute(attr_name, time) + clear_attribute_change(attr_name) + end + + _update_row(attribute_names, "touch") + end + + def _update_row(attribute_names, attempted_action = "update") + self.class._update_record( + attributes_with_values(attribute_names), + self.class.primary_key => id_in_database + ) + end + + def create_or_update(*args, &block) _raise_readonly_record_error if readonly? - result = new_record? ? _create_record : _update_record(*args) + return false if destroyed? + result = new_record? ? _create_record(&block) : _update_record(*args, &block) result != false end # Updates the associated record with values matching those of the instance attributes. # Returns the number of affected rows. def _update_record(attribute_names = self.attribute_names) - attributes_values = arel_attributes_with_values_for_update(attribute_names) - if attributes_values.empty? - rows_affected = 0 + attribute_names = attributes_for_update(attribute_names) + + if attribute_names.empty? + affected_rows = 0 @_trigger_update_callback = true else - rows_affected = self.class.unscoped._update_record attributes_values, id, id_in_database - @_trigger_update_callback = rows_affected > 0 + affected_rows = _update_row(attribute_names) + @_trigger_update_callback = affected_rows == 1 end - rows_affected + + yield(self) if block_given? + + affected_rows end # Creates a record with values matching those of the instance attributes # and returns its id. def _create_record(attribute_names = self.attribute_names) - attributes_values = arel_attributes_with_values_for_create(attribute_names) + attribute_names = attributes_for_create(attribute_names) + + new_id = self.class._insert_record( + attributes_with_values(attribute_names) + ) - new_id = self.class.unscoped.insert attributes_values self.id ||= new_id if self.class.primary_key @new_record = false + + yield(self) if block_given? + id end |