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Diffstat (limited to 'activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb')
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb | 702 |
1 files changed, 702 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb new file mode 100644 index 0000000000..db489143af --- /dev/null +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb @@ -0,0 +1,702 @@ +# frozen_string_literal: true + +require "active_support/deprecation" + +module ActiveRecord + module ConnectionAdapters #:nodoc: + # Abstract representation of an index definition on a table. Instances of + # this type are typically created and returned by methods in database + # adapters. e.g. ActiveRecord::ConnectionAdapters::MySQL::SchemaStatements#indexes + class IndexDefinition # :nodoc: + attr_reader :table, :name, :unique, :columns, :lengths, :orders, :opclasses, :where, :type, :using, :comment + + def initialize( + table, name, + unique = false, + columns = [], + lengths: {}, + orders: {}, + opclasses: {}, + where: nil, + type: nil, + using: nil, + comment: nil + ) + @table = table + @name = name + @unique = unique + @columns = columns + @lengths = concise_options(lengths) + @orders = concise_options(orders) + @opclasses = concise_options(opclasses) + @where = where + @type = type + @using = using + @comment = comment + end + + private + def concise_options(options) + if columns.size == options.size && options.values.uniq.size == 1 + options.values.first + else + options + end + end + end + + # Abstract representation of a column definition. Instances of this type + # are typically created by methods in TableDefinition, and added to the + # +columns+ attribute of said TableDefinition object, in order to be used + # for generating a number of table creation or table changing SQL statements. + ColumnDefinition = Struct.new(:name, :type, :options, :sql_type) do # :nodoc: + def primary_key? + options[:primary_key] + end + + [:limit, :precision, :scale, :default, :null, :collation, :comment].each do |option_name| + module_eval <<-CODE, __FILE__, __LINE__ + 1 + def #{option_name} + options[:#{option_name}] + end + + def #{option_name}=(value) + options[:#{option_name}] = value + end + CODE + end + end + + AddColumnDefinition = Struct.new(:column) # :nodoc: + + ChangeColumnDefinition = Struct.new(:column, :name) #:nodoc: + + PrimaryKeyDefinition = Struct.new(:name) # :nodoc: + + ForeignKeyDefinition = Struct.new(:from_table, :to_table, :options) do #:nodoc: + def name + options[:name] + end + + def column + options[:column] + end + + def primary_key + options[:primary_key] || default_primary_key + end + + def on_delete + options[:on_delete] + end + + def on_update + options[:on_update] + end + + def custom_primary_key? + options[:primary_key] != default_primary_key + end + + def validate? + options.fetch(:validate, true) + end + alias validated? validate? + + def export_name_on_schema_dump? + name !~ ActiveRecord::SchemaDumper.fk_ignore_pattern + end + + def defined_for?(to_table_ord = nil, to_table: nil, **options) + if to_table_ord + self.to_table == to_table_ord.to_s + else + (to_table.nil? || to_table.to_s == self.to_table) && + options.all? { |k, v| self.options[k].to_s == v.to_s } + end + end + + private + def default_primary_key + "id" + end + end + + class ReferenceDefinition # :nodoc: + def initialize( + name, + polymorphic: false, + index: true, + foreign_key: false, + type: :bigint, + **options + ) + @name = name + @polymorphic = polymorphic + @index = index + @foreign_key = foreign_key + @type = type + @options = options + + if polymorphic && foreign_key + raise ArgumentError, "Cannot add a foreign key to a polymorphic relation" + end + end + + def add_to(table) + columns.each do |column_options| + table.column(*column_options) + end + + if index + table.index(column_names, index_options) + end + + if foreign_key + table.foreign_key(foreign_table_name, foreign_key_options) + end + end + + private + attr_reader :name, :polymorphic, :index, :foreign_key, :type, :options + + def as_options(value) + value.is_a?(Hash) ? value : {} + end + + def polymorphic_options + as_options(polymorphic).merge(options.slice(:null, :first, :after)) + end + + def index_options + as_options(index) + end + + def foreign_key_options + as_options(foreign_key).merge(column: column_name) + end + + def columns + result = [[column_name, type, options]] + if polymorphic + result.unshift(["#{name}_type", :string, polymorphic_options]) + end + result + end + + def column_name + "#{name}_id" + end + + def column_names + columns.map(&:first) + end + + def foreign_table_name + foreign_key_options.fetch(:to_table) do + Base.pluralize_table_names ? name.to_s.pluralize : name + end + end + end + + module ColumnMethods + # Appends a primary key definition to the table definition. + # Can be called multiple times, but this is probably not a good idea. + def primary_key(name, type = :primary_key, **options) + column(name, type, options.merge(primary_key: true)) + end + + # Appends a column or columns of a specified type. + # + # t.string(:goat) + # t.string(:goat, :sheep) + # + # See TableDefinition#column + [ + :bigint, + :binary, + :boolean, + :date, + :datetime, + :decimal, + :float, + :integer, + :json, + :string, + :text, + :time, + :timestamp, + :virtual, + ].each do |column_type| + module_eval <<-CODE, __FILE__, __LINE__ + 1 + def #{column_type}(*args, **options) + args.each { |name| column(name, :#{column_type}, options) } + end + CODE + end + alias_method :numeric, :decimal + end + + # Represents the schema of an SQL table in an abstract way. This class + # provides methods for manipulating the schema representation. + # + # Inside migration files, the +t+ object in {create_table}[rdoc-ref:SchemaStatements#create_table] + # is actually of this type: + # + # class SomeMigration < ActiveRecord::Migration[5.0] + # def up + # create_table :foo do |t| + # puts t.class # => "ActiveRecord::ConnectionAdapters::TableDefinition" + # end + # end + # + # def down + # ... + # end + # end + # + class TableDefinition + include ColumnMethods + + attr_reader :name, :temporary, :if_not_exists, :options, :as, :comment, :indexes, :foreign_keys + attr_writer :indexes + deprecate :indexes= + + def initialize( + name, + temporary: false, + if_not_exists: false, + options: nil, + as: nil, + comment: nil, + ** + ) + @columns_hash = {} + @indexes = [] + @foreign_keys = [] + @primary_keys = nil + @temporary = temporary + @if_not_exists = if_not_exists + @options = options + @as = as + @name = name + @comment = comment + end + + def primary_keys(name = nil) # :nodoc: + @primary_keys = PrimaryKeyDefinition.new(name) if name + @primary_keys + end + + # Returns an array of ColumnDefinition objects for the columns of the table. + def columns; @columns_hash.values; end + + # Returns a ColumnDefinition for the column with name +name+. + def [](name) + @columns_hash[name.to_s] + end + + # Instantiates a new column for the table. + # See {connection.add_column}[rdoc-ref:ConnectionAdapters::SchemaStatements#add_column] + # for available options. + # + # Additional options are: + # * <tt>:index</tt> - + # Create an index for the column. Can be either <tt>true</tt> or an options hash. + # + # This method returns <tt>self</tt>. + # + # == Examples + # + # # Assuming +td+ is an instance of TableDefinition + # td.column(:granted, :boolean, index: true) + # + # == Short-hand examples + # + # Instead of calling #column directly, you can also work with the short-hand definitions for the default types. + # They use the type as the method name instead of as a parameter and allow for multiple columns to be defined + # in a single statement. + # + # What can be written like this with the regular calls to column: + # + # create_table :products do |t| + # t.column :shop_id, :integer + # t.column :creator_id, :integer + # t.column :item_number, :string + # t.column :name, :string, default: "Untitled" + # t.column :value, :string, default: "Untitled" + # t.column :created_at, :datetime + # t.column :updated_at, :datetime + # end + # add_index :products, :item_number + # + # can also be written as follows using the short-hand: + # + # create_table :products do |t| + # t.integer :shop_id, :creator_id + # t.string :item_number, index: true + # t.string :name, :value, default: "Untitled" + # t.timestamps null: false + # end + # + # There's a short-hand method for each of the type values declared at the top. And then there's + # TableDefinition#timestamps that'll add +created_at+ and +updated_at+ as datetimes. + # + # TableDefinition#references will add an appropriately-named _id column, plus a corresponding _type + # column if the <tt>:polymorphic</tt> option is supplied. If <tt>:polymorphic</tt> is a hash of + # options, these will be used when creating the <tt>_type</tt> column. The <tt>:index</tt> option + # will also create an index, similar to calling {add_index}[rdoc-ref:ConnectionAdapters::SchemaStatements#add_index]. + # So what can be written like this: + # + # create_table :taggings do |t| + # t.integer :tag_id, :tagger_id, :taggable_id + # t.string :tagger_type + # t.string :taggable_type, default: 'Photo' + # end + # add_index :taggings, :tag_id, name: 'index_taggings_on_tag_id' + # add_index :taggings, [:tagger_id, :tagger_type] + # + # Can also be written as follows using references: + # + # create_table :taggings do |t| + # t.references :tag, index: { name: 'index_taggings_on_tag_id' } + # t.references :tagger, polymorphic: true + # t.references :taggable, polymorphic: { default: 'Photo' }, index: false + # end + def column(name, type, options = {}) + name = name.to_s + type = type.to_sym if type + options = options.dup + + if @columns_hash[name] + if @columns_hash[name].primary_key? + raise ArgumentError, "you can't redefine the primary key column '#{name}'. To define a custom primary key, pass { id: false } to create_table." + else + raise ArgumentError, "you can't define an already defined column '#{name}'." + end + end + + index_options = options.delete(:index) + index(name, index_options.is_a?(Hash) ? index_options : {}) if index_options + @columns_hash[name] = new_column_definition(name, type, options) + self + end + + # remove the column +name+ from the table. + # remove_column(:account_id) + def remove_column(name) + @columns_hash.delete name.to_s + end + + # Adds index options to the indexes hash, keyed by column name + # This is primarily used to track indexes that need to be created after the table + # + # index(:account_id, name: 'index_projects_on_account_id') + def index(column_name, options = {}) + indexes << [column_name, options] + end + + def foreign_key(table_name, options = {}) # :nodoc: + table_name_prefix = ActiveRecord::Base.table_name_prefix + table_name_suffix = ActiveRecord::Base.table_name_suffix + table_name = "#{table_name_prefix}#{table_name}#{table_name_suffix}" + foreign_keys.push([table_name, options]) + end + + # Appends <tt>:datetime</tt> columns <tt>:created_at</tt> and + # <tt>:updated_at</tt> to the table. See {connection.add_timestamps}[rdoc-ref:SchemaStatements#add_timestamps] + # + # t.timestamps null: false + def timestamps(**options) + options[:null] = false if options[:null].nil? + + column(:created_at, :datetime, options) + column(:updated_at, :datetime, options) + end + + # Adds a reference. + # + # t.references(:user) + # t.belongs_to(:supplier, foreign_key: true) + # + # See {connection.add_reference}[rdoc-ref:SchemaStatements#add_reference] for details of the options you can use. + def references(*args, **options) + args.each do |ref_name| + ReferenceDefinition.new(ref_name, options).add_to(self) + end + end + alias :belongs_to :references + + def new_column_definition(name, type, **options) # :nodoc: + if integer_like_primary_key?(type, options) + type = integer_like_primary_key_type(type, options) + end + type = aliased_types(type.to_s, type) + options[:primary_key] ||= type == :primary_key + options[:null] = false if options[:primary_key] + create_column_definition(name, type, options) + end + + private + def create_column_definition(name, type, options) + ColumnDefinition.new(name, type, options) + end + + def aliased_types(name, fallback) + "timestamp" == name ? :datetime : fallback + end + + def integer_like_primary_key?(type, options) + options[:primary_key] && [:integer, :bigint].include?(type) && !options.key?(:default) + end + + def integer_like_primary_key_type(type, options) + type + end + end + + class AlterTable # :nodoc: + attr_reader :adds + attr_reader :foreign_key_adds + attr_reader :foreign_key_drops + + def initialize(td) + @td = td + @adds = [] + @foreign_key_adds = [] + @foreign_key_drops = [] + end + + def name; @td.name; end + + def add_foreign_key(to_table, options) + @foreign_key_adds << ForeignKeyDefinition.new(name, to_table, options) + end + + def drop_foreign_key(name) + @foreign_key_drops << name + end + + def add_column(name, type, options) + name = name.to_s + type = type.to_sym + @adds << AddColumnDefinition.new(@td.new_column_definition(name, type, options)) + end + end + + # Represents an SQL table in an abstract way for updating a table. + # Also see TableDefinition and {connection.create_table}[rdoc-ref:SchemaStatements#create_table] + # + # Available transformations are: + # + # change_table :table do |t| + # t.primary_key + # t.column + # t.index + # t.rename_index + # t.timestamps + # t.change + # t.change_default + # t.rename + # t.references + # t.belongs_to + # t.string + # t.text + # t.integer + # t.bigint + # t.float + # t.decimal + # t.numeric + # t.datetime + # t.timestamp + # t.time + # t.date + # t.binary + # t.boolean + # t.foreign_key + # t.json + # t.virtual + # t.remove + # t.remove_references + # t.remove_belongs_to + # t.remove_index + # t.remove_timestamps + # end + # + class Table + include ColumnMethods + + attr_reader :name + + def initialize(table_name, base) + @name = table_name + @base = base + end + + # Adds a new column to the named table. + # + # t.column(:name, :string) + # + # See TableDefinition#column for details of the options you can use. + def column(column_name, type, options = {}) + index_options = options.delete(:index) + @base.add_column(name, column_name, type, options) + index(column_name, index_options.is_a?(Hash) ? index_options : {}) if index_options + end + + # Checks to see if a column exists. + # + # t.string(:name) unless t.column_exists?(:name, :string) + # + # See {connection.column_exists?}[rdoc-ref:SchemaStatements#column_exists?] + def column_exists?(column_name, type = nil, options = {}) + @base.column_exists?(name, column_name, type, options) + end + + # Adds a new index to the table. +column_name+ can be a single Symbol, or + # an Array of Symbols. + # + # t.index(:name) + # t.index([:branch_id, :party_id], unique: true) + # t.index([:branch_id, :party_id], unique: true, name: 'by_branch_party') + # + # See {connection.add_index}[rdoc-ref:SchemaStatements#add_index] for details of the options you can use. + def index(column_name, options = {}) + @base.add_index(name, column_name, options) + end + + # Checks to see if an index exists. + # + # unless t.index_exists?(:branch_id) + # t.index(:branch_id) + # end + # + # See {connection.index_exists?}[rdoc-ref:SchemaStatements#index_exists?] + def index_exists?(column_name, options = {}) + @base.index_exists?(name, column_name, options) + end + + # Renames the given index on the table. + # + # t.rename_index(:user_id, :account_id) + # + # See {connection.rename_index}[rdoc-ref:SchemaStatements#rename_index] + def rename_index(index_name, new_index_name) + @base.rename_index(name, index_name, new_index_name) + end + + # Adds timestamps (+created_at+ and +updated_at+) columns to the table. + # + # t.timestamps(null: false) + # + # See {connection.add_timestamps}[rdoc-ref:SchemaStatements#add_timestamps] + def timestamps(options = {}) + @base.add_timestamps(name, options) + end + + # Changes the column's definition according to the new options. + # + # t.change(:name, :string, limit: 80) + # t.change(:description, :text) + # + # See TableDefinition#column for details of the options you can use. + def change(column_name, type, options = {}) + @base.change_column(name, column_name, type, options) + end + + # Sets a new default value for a column. + # + # t.change_default(:qualification, 'new') + # t.change_default(:authorized, 1) + # t.change_default(:status, from: nil, to: "draft") + # + # See {connection.change_column_default}[rdoc-ref:SchemaStatements#change_column_default] + def change_default(column_name, default_or_changes) + @base.change_column_default(name, column_name, default_or_changes) + end + + # Removes the column(s) from the table definition. + # + # t.remove(:qualification) + # t.remove(:qualification, :experience) + # + # See {connection.remove_columns}[rdoc-ref:SchemaStatements#remove_columns] + def remove(*column_names) + @base.remove_columns(name, *column_names) + end + + # Removes the given index from the table. + # + # t.remove_index(:branch_id) + # t.remove_index(column: [:branch_id, :party_id]) + # t.remove_index(name: :by_branch_party) + # + # See {connection.remove_index}[rdoc-ref:SchemaStatements#remove_index] + def remove_index(options = {}) + @base.remove_index(name, options) + end + + # Removes the timestamp columns (+created_at+ and +updated_at+) from the table. + # + # t.remove_timestamps + # + # See {connection.remove_timestamps}[rdoc-ref:SchemaStatements#remove_timestamps] + def remove_timestamps(options = {}) + @base.remove_timestamps(name, options) + end + + # Renames a column. + # + # t.rename(:description, :name) + # + # See {connection.rename_column}[rdoc-ref:SchemaStatements#rename_column] + def rename(column_name, new_column_name) + @base.rename_column(name, column_name, new_column_name) + end + + # Adds a reference. + # + # t.references(:user) + # t.belongs_to(:supplier, foreign_key: true) + # + # See {connection.add_reference}[rdoc-ref:SchemaStatements#add_reference] for details of the options you can use. + def references(*args, **options) + args.each do |ref_name| + @base.add_reference(name, ref_name, options) + end + end + alias :belongs_to :references + + # Removes a reference. Optionally removes a +type+ column. + # + # t.remove_references(:user) + # t.remove_belongs_to(:supplier, polymorphic: true) + # + # See {connection.remove_reference}[rdoc-ref:SchemaStatements#remove_reference] + def remove_references(*args, **options) + args.each do |ref_name| + @base.remove_reference(name, ref_name, options) + end + end + alias :remove_belongs_to :remove_references + + # Adds a foreign key. + # + # t.foreign_key(:authors) + # + # See {connection.add_foreign_key}[rdoc-ref:SchemaStatements#add_foreign_key] + def foreign_key(*args) + @base.add_foreign_key(name, *args) + end + + # Checks to see if a foreign key exists. + # + # t.foreign_key(:authors) unless t.foreign_key_exists?(:authors) + # + # See {connection.foreign_key_exists?}[rdoc-ref:SchemaStatements#foreign_key_exists?] + def foreign_key_exists?(*args) + @base.foreign_key_exists?(name, *args) + end + end + end +end |