diff options
Diffstat (limited to 'activerecord/lib')
10 files changed, 338 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb index 47fe501752..c1379f6bec 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb @@ -23,6 +23,8 @@ module ActiveRecord def visit_AlterTable(o) sql = "ALTER TABLE #{quote_table_name(o.name)} " sql << o.adds.map { |col| visit_AddColumn col }.join(' ') + sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(' ') + sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(' ') end def visit_ColumnDefinition(o) @@ -41,6 +43,21 @@ module ActiveRecord create_sql end + def visit_AddForeignKey(o) + sql = <<-SQL.strip_heredoc + ADD CONSTRAINT #{quote_column_name(o.name)} + FOREIGN KEY (#{quote_column_name(o.column)}) + REFERENCES #{quote_table_name(o.to_table)} (#{quote_column_name(o.primary_key)}) + SQL + sql << " #{action_sql('DELETE', o.on_delete)}" if o.on_delete + sql << " #{action_sql('UPDATE', o.on_update)}" if o.on_update + sql + end + + def visit_DropForeignKey(name) + "DROP CONSTRAINT #{quote_column_name(name)}" + end + def column_options(o) column_options = {} column_options[:null] = o.null unless o.null.nil? @@ -84,6 +101,19 @@ module ActiveRecord def options_include_default?(options) options.include?(:default) && !(options[:null] == false && options[:default].nil?) end + + def action_sql(action, dependency) + case dependency + when :nullify then "ON #{action} SET NULL" + when :cascade then "ON #{action} CASCADE" + when :restrict then "ON #{action} RESTRICT" + else + raise ArgumentError, <<-MSG.strip_heredoc + '#{dependency}' is not supported for :on_update or :on_delete. + Supported values are: :nullify, :cascade, :restrict + MSG + end + end end end end diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb index a9b3e9cfb9..785cfd9dbc 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb @@ -25,6 +25,37 @@ module ActiveRecord class ChangeColumnDefinition < Struct.new(:column, :type, :options) #:nodoc: end + class ForeignKeyDefinition < Struct.new(:from_table, :to_table, :options) + 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 + + private + def default_primary_key + "id" + end + end + # Represents the schema of an SQL table in an abstract way. This class # provides methods for manipulating the schema representation. # @@ -303,14 +334,26 @@ module ActiveRecord 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 diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 22823a8c58..5814c2b711 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -642,6 +642,115 @@ module ActiveRecord end alias :remove_belongs_to :remove_reference + # Returns an array of foreign keys for the given table. + # The foreign keys are represented as +ForeignKeyDefinition+ objects. + def foreign_keys(table_name) + raise NotImplementedError, "foreign_keys is not implemented" + end + + # Adds a new foreign key. +from_table+ is the table with the key column, + # +to_table+ contains the referenced primary key. + # + # The foreign key will be named after the following pattern: <tt>fk_rails_<identifier></tt>. + # +identifier+ is a 10 character long random string. A custom name can be specified with + # the <tt>:name</tt> option. + # + # ====== Creating a simple foreign key + # + # add_foreign_key :articles, :authors + # + # generates: + # + # ALTER TABLE "articles" ADD CONSTRAINT articles_author_id_fk FOREIGN KEY ("author_id") REFERENCES "authors" ("id") + # + # ====== Creating a foreign key on a specific column + # + # add_foreign_key :articles, :users, column: :author_id, primary_key: "lng_id" + # + # generates: + # + # ALTER TABLE "articles" ADD CONSTRAINT fk_rails_58ca3d3a82 FOREIGN KEY ("author_id") REFERENCES "users" ("lng_id") + # + # ====== Creating a cascading foreign key + # + # add_foreign_key :articles, :authors, on_delete: :cascade + # + # generates: + # + # ALTER TABLE "articles" ADD CONSTRAINT articles_author_id_fk FOREIGN KEY ("author_id") REFERENCES "authors" ("id") ON DELETE CASCADE + # + # The +options+ hash can include the following keys: + # [<tt>:column</tt>] + # The foreign key column name on +from_table+. Defaults to <tt>to_table.singularize + "_id"</tt> + # [<tt>:primary_key</tt>] + # The primary key column name on +to_table+. Defaults to +id+. + # [<tt>:name</tt>] + # The constraint name. Defaults to <tt>fk_rails_<identifier></tt>. + # [<tt>:on_delete</tt>] + # Action that happens <tt>ON DELETE</tt>. Valid values are +:nullify+, +:cascade:+ and +:restrict+ + # [<tt>:on_update</tt>] + # Action that happens <tt>ON UPDATE</tt>. Valid values are +:nullify+, +:cascade:+ and +:restrict+ + def add_foreign_key(from_table, to_table, options = {}) + return unless supports_foreign_keys? + + options[:column] ||= foreign_key_column_for(to_table) + + options = { + column: options[:column], + primary_key: options[:primary_key], + name: foreign_key_name(from_table, options), + on_delete: options[:on_delete], + on_update: options[:on_update] + } + at = create_alter_table from_table + at.add_foreign_key to_table, options + + execute schema_creation.accept(at) + end + + # Removes the given foreign key from the table. + # + # Removes the foreign key on +accounts.branch_id+. + # + # remove_foreign_key :accounts, :branches + # + # Removes the foreign key on +accounts.owner_id+. + # + # remove_foreign_key :accounts, column: :owner_id + # + # Removes the foreign key named +special_fk_name+ on the +accounts+ table. + # + # remove_foreign_key :accounts, name: :special_fk_name + # + def remove_foreign_key(from_table, options_or_to_table = {}) + return unless supports_foreign_keys? + + if options_or_to_table.is_a?(Hash) + options = options_or_to_table + else + options = { column: foreign_key_column_for(options_or_to_table) } + end + + fk_name_to_delete = options.fetch(:name) do + fk_to_delete = foreign_keys(from_table).detect {|fk| fk.column == options[:column] } + + if fk_to_delete + fk_to_delete.name + else + raise ArgumentError, "Table '#{from_table}' has no foreign key on column '#{options[:column]}'" + end + end + + at = create_alter_table from_table + at.drop_foreign_key fk_name_to_delete + + execute schema_creation.accept(at) + end + + def foreign_key_column_for(table_name) # :nodoc: + "#{table_name.to_s.singularize}_id" + end + def dump_schema_information #:nodoc: sm_table = ActiveRecord::Migrator.schema_migrations_table_name @@ -852,6 +961,12 @@ module ActiveRecord def create_alter_table(name) AlterTable.new create_table_definition(name, false, {}) end + + def foreign_key_name(table_name, options) # :nodoc: + options.fetch(:name) do + "fk_rails_#{SecureRandom.hex(5)}" + end + end end end end diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb index cc494a7f40..294ed6d7bf 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb @@ -233,6 +233,11 @@ module ActiveRecord false end + # Does this adapter support creating foreign key constraints? + def supports_foreign_keys? + false + end + # This is meant to be implemented by the adapters that support extensions def disable_extension(name) end diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb index def04dbed2..4924f345fc 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb @@ -10,6 +10,10 @@ module ActiveRecord add_column_position!(super, column_options(o)) end + def visit_DropForeignKey(name) + "DROP FOREIGN KEY #{name}" + end + private def visit_TableDefinition(o) @@ -192,6 +196,10 @@ module ActiveRecord true end + def supports_foreign_keys? + true + end + def native_database_types NATIVE_DATABASE_TYPES end @@ -501,6 +509,34 @@ module ActiveRecord execute "CREATE #{index_type} INDEX #{quote_column_name(index_name)} #{index_using} ON #{quote_table_name(table_name)} (#{index_columns})#{index_options} #{index_algorithm}" end + def foreign_keys(table_name) + fk_info = select_all <<-SQL.strip_heredoc + SELECT fk.referenced_table_name as 'to_table' + ,fk.referenced_column_name as 'primary_key' + ,fk.column_name as 'column' + ,fk.constraint_name as 'name' + FROM information_schema.key_column_usage fk + WHERE fk.referenced_column_name is not null + AND fk.table_schema = '#{@config[:database]}' + AND fk.table_name = '#{table_name}' + SQL + + create_table_info = select_one("SHOW CREATE TABLE #{quote_table_name(table_name)}")["Create Table"] + + fk_info.map do |row| + options = { + column: row['column'], + name: row['name'], + primary_key: row['primary_key'] + } + + options[:on_update] = extract_foreign_key_action(create_table_info, row['name'], "UPDATE") + options[:on_delete] = extract_foreign_key_action(create_table_info, row['name'], "DELETE") + + ForeignKeyDefinition.new(table_name, row['to_table'], options) + end + end + # Maps logical Rails types to MySQL-specific data types. def type_to_sql(type, limit = nil, precision = nil, scale = nil) case type.to_s @@ -779,6 +815,15 @@ module ActiveRecord # ...and send them all in one query @connection.query "SET #{encoding} #{variable_assignments}" end + + def extract_foreign_key_action(structure, name, action) # :nodoc: + if structure =~ /CONSTRAINT #{quote_column_name(name)} FOREIGN KEY .* REFERENCES .* ON #{action} (CASCADE|SET NULL|RESTRICT)/ + case $1 + when 'CASCADE'; :cascade + when 'SET NULL'; :nullify + end + end + end end end end diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb index b2aeb3a058..30df98be1b 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb @@ -448,6 +448,42 @@ module ActiveRecord execute "ALTER INDEX #{quote_column_name(old_name)} RENAME TO #{quote_table_name(new_name)}" end + def foreign_keys(table_name) + fk_info = select_all <<-SQL.strip_heredoc + SELECT t2.relname AS to_table, a1.attname AS column, a2.attname AS primary_key, c.conname AS name, c.confupdtype AS on_update, c.confdeltype AS on_delete + FROM pg_constraint c + JOIN pg_class t1 ON c.conrelid = t1.oid + JOIN pg_class t2 ON c.confrelid = t2.oid + JOIN pg_attribute a1 ON a1.attnum = c.conkey[1] AND a1.attrelid = t1.oid + JOIN pg_attribute a2 ON a2.attnum = c.confkey[1] AND a2.attrelid = t2.oid + JOIN pg_namespace t3 ON c.connamespace = t3.oid + WHERE c.contype = 'f' + AND t1.relname = #{quote(table_name)} + AND t3.nspname = ANY (current_schemas(false)) + ORDER BY c.conname + SQL + + fk_info.map do |row| + options = { + column: row['column'], + name: row['name'], + primary_key: row['primary_key'] + } + + options[:on_delete] = extract_foreign_key_action(row['on_delete']) + options[:on_update] = extract_foreign_key_action(row['on_update']) + ForeignKeyDefinition.new(table_name, row['to_table'], options) + end + end + + def extract_foreign_key_action(specifier) # :nodoc: + case specifier + when 'c'; :cascade + when 'n'; :nullify + when 'r'; :restrict + end + end + def index_name_length 63 end diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb index be4ae47d09..34262cf91d 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb @@ -159,6 +159,10 @@ module ActiveRecord true end + def supports_foreign_keys? + true + end + def index_algorithms { concurrently: 'CONCURRENTLY' } end diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb index 01c001e692..12eaf36156 100644 --- a/activerecord/lib/active_record/migration.rb +++ b/activerecord/lib/active_record/migration.rb @@ -645,7 +645,9 @@ module ActiveRecord unless @connection.respond_to? :revert unless arguments.empty? || [:execute, :enable_extension, :disable_extension].include?(method) arguments[0] = proper_table_name(arguments.first, table_name_options) - arguments[1] = proper_table_name(arguments.second, table_name_options) if method == :rename_table + if [:rename_table, :add_foreign_key].include?(method) + arguments[1] = proper_table_name(arguments.second, table_name_options) + end end end return super unless connection.respond_to?(method) diff --git a/activerecord/lib/active_record/migration/command_recorder.rb b/activerecord/lib/active_record/migration/command_recorder.rb index c44d8c1665..f833caaab6 100644 --- a/activerecord/lib/active_record/migration/command_recorder.rb +++ b/activerecord/lib/active_record/migration/command_recorder.rb @@ -74,7 +74,9 @@ module ActiveRecord :rename_index, :rename_column, :add_index, :remove_index, :add_timestamps, :remove_timestamps, :change_column_default, :add_reference, :remove_reference, :transaction, :drop_join_table, :drop_table, :execute_block, :enable_extension, - :change_column, :execute, :remove_columns, :change_column_null # irreversible methods need to be here too + :change_column, :execute, :remove_columns, :change_column_null, + :add_foreign_key, :remove_foreign_key + # irreversible methods need to be here too ].each do |method| class_eval <<-EOV, __FILE__, __LINE__ + 1 def #{method}(*args, &block) # def create_table(*args, &block) @@ -167,6 +169,21 @@ module ActiveRecord [:change_column_null, args] end + def invert_add_foreign_key(args) + from_table, to_table, add_options = args + add_options ||= {} + + if add_options[:name] + options = { name: add_options[:name] } + elsif add_options[:column] + options = { column: add_options[:column] } + else + options = to_table + end + + [:remove_foreign_key, [from_table, options]] + end + # Forwards any missing method call to the \target. def method_missing(method, *args, &block) if @delegate.respond_to?(method) diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb index e055d571ab..64bc68eefd 100644 --- a/activerecord/lib/active_record/schema_dumper.rb +++ b/activerecord/lib/active_record/schema_dumper.rb @@ -91,7 +91,8 @@ HEADER end def tables(stream) - @connection.tables.sort.each do |tbl| + sorted_tables = @connection.tables.sort + sorted_tables.each do |tbl| next if ['schema_migrations', ignore_tables].flatten.any? do |ignored| case ignored when String; remove_prefix_and_suffix(tbl) == ignored @@ -102,6 +103,13 @@ HEADER end table(tbl, stream) end + + # dump foreign keys at the end to make sure all dependent tables exist. + if @connection.supports_foreign_keys? + sorted_tables.each do |tbl| + foreign_keys(tbl, stream) + end + end end def table(table, stream) @@ -212,6 +220,36 @@ HEADER end end + def foreign_keys(table, stream) + if (foreign_keys = @connection.foreign_keys(table)).any? + add_foreign_key_statements = foreign_keys.map do |foreign_key| + parts = [ + 'add_foreign_key ' + remove_prefix_and_suffix(foreign_key.from_table).inspect, + remove_prefix_and_suffix(foreign_key.to_table).inspect, + ] + + if foreign_key.column != @connection.foreign_key_column_for(foreign_key.to_table) + parts << ('column: ' + foreign_key.column.inspect) + end + + if foreign_key.custom_primary_key? + parts << ('primary_key: ' + foreign_key.primary_key.inspect) + end + + if foreign_key.name !~ /^fk_rails_[0-9a-f]{10}$/ + parts << ('name: ' + foreign_key.name.inspect) + end + + parts << ('on_update: ' + foreign_key.on_update.inspect) if foreign_key.on_update + parts << ('on_delete: ' + foreign_key.on_delete.inspect) if foreign_key.on_delete + + ' ' + parts.join(', ') + end + + stream.puts add_foreign_key_statements.sort.join("\n") + end + end + def remove_prefix_and_suffix(table) table.gsub(/^(#{@options[:table_name_prefix]})(.+)(#{@options[:table_name_suffix]})$/, "\\2") end |