Merge pull request #15606 from senny/ar/foreign_key_support

Basic support for adding and removing foreign keys

2 files changed, 267 insertions, 0 deletions

diff --git a/activerecord/test/cases/migration/command_recorder_test.rb b/activerecord/test/cases/migration/command_recorder_test.rb
index 1c0134843b..e955beae1a 100644
--- a/activerecord/test/cases/migration/command_recorder_test.rb
+++ b/activerecord/test/cases/migration/command_recorder_test.rb
@@ -270,6 +270,31 @@ module ActiveRecord
         enable = @recorder.inverse_of :disable_extension, ['uuid-ossp']
         assert_equal [:enable_extension, ['uuid-ossp'], nil], enable
       end
+
+      def test_invert_add_foreign_key
+        enable = @recorder.inverse_of :add_foreign_key, [:dogs, :people]
+        assert_equal [:remove_foreign_key, [:dogs, :people]], enable
+      end
+
+      def test_invert_add_foreign_key_with_column
+        enable = @recorder.inverse_of :add_foreign_key, [:dogs, :people, column: "owner_id"]
+        assert_equal [:remove_foreign_key, [:dogs, column: "owner_id"]], enable
+      end
+
+      def test_invert_add_foreign_key_with_column_and_name
+        enable = @recorder.inverse_of :add_foreign_key, [:dogs, :people, column: "owner_id", name: "fk"]
+        assert_equal [:remove_foreign_key, [:dogs, name: "fk"]], enable
+      end
+
+      def test_remove_foreign_key_is_irreversible
+        assert_raises ActiveRecord::IrreversibleMigration do
+          @recorder.inverse_of :remove_foreign_key, [:dogs, column: "owner_id"]
+        end
+
+        assert_raises ActiveRecord::IrreversibleMigration do
+          @recorder.inverse_of :remove_foreign_key, [:dogs, name: "fk"]
+        end
+      end
     end
   end
 end
diff --git a/activerecord/test/cases/migration/foreign_key_test.rb b/activerecord/test/cases/migration/foreign_key_test.rb
new file mode 100644
index 0000000000..c985092b4c
--- /dev/null
+++ b/activerecord/test/cases/migration/foreign_key_test.rb
@@ -0,0 +1,242 @@
+require 'cases/helper'
+require 'support/ddl_helper'
+require 'support/schema_dumping_helper'
+
+if ActiveRecord::Base.connection.supports_foreign_keys?
+module ActiveRecord
+  class Migration
+    class ForeignKeyTest < ActiveRecord::TestCase
+      include DdlHelper
+      include SchemaDumpingHelper
+
+      class Rocket < ActiveRecord::Base
+      end
+
+      class Astronaut < ActiveRecord::Base
+      end
+
+      setup do
+        @connection = ActiveRecord::Base.connection
+        @connection.create_table "rockets" do |t|
+          t.string :name
+        end
+
+        @connection.create_table "astronauts" do |t|
+          t.string :name
+          t.references :rocket
+        end
+      end
+
+      teardown do
+        if defined?(@connection)
+          @connection.execute "DROP TABLE IF EXISTS astronauts"
+          @connection.execute "DROP TABLE IF EXISTS rockets"
+        end
+      end
+
+      def test_foreign_keys
+        foreign_keys = @connection.foreign_keys("fk_test_has_fk")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal "fk_test_has_fk", fk.from_table
+        assert_equal "fk_test_has_pk", fk.to_table
+        assert_equal "fk_id", fk.column
+        assert_equal "pk_id", fk.primary_key
+        assert_equal "fk_name", fk.name
+      end
+
+      def test_add_foreign_key_inferes_column
+        @connection.add_foreign_key :astronauts, :rockets
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal "astronauts", fk.from_table
+        assert_equal "rockets", fk.to_table
+        assert_equal "rocket_id", fk.column
+        assert_equal "id", fk.primary_key
+        assert_match(/^fk_rails_.{10}$/, fk.name)
+      end
+
+      def test_add_foreign_key_with_column
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal "astronauts", fk.from_table
+        assert_equal "rockets", fk.to_table
+        assert_equal "rocket_id", fk.column
+        assert_equal "id", fk.primary_key
+        assert_match(/^fk_rails_.{10}$/, fk.name)
+      end
+
+      def test_add_foreign_key_with_non_standard_primary_key
+        with_example_table @connection, "space_shuttles", "pk integer PRIMARY KEY" do
+          @connection.add_foreign_key(:astronauts, :space_shuttles,
+                                      column: "rocket_id", primary_key: "pk", name: "custom_pk")
+
+          foreign_keys = @connection.foreign_keys("astronauts")
+          assert_equal 1, foreign_keys.size
+
+          fk = foreign_keys.first
+          assert_equal "astronauts", fk.from_table
+          assert_equal "space_shuttles", fk.to_table
+          assert_equal "pk", fk.primary_key
+
+          @connection.remove_foreign_key :astronauts, name: "custom_pk"
+        end
+      end
+
+      def test_add_on_delete_restrict_foreign_key
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :restrict
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        if current_adapter?(:MysqlAdapter, :Mysql2Adapter)
+          # ON DELETE RESTRICT is the default on MySQL
+          assert_equal nil, fk.on_delete
+        else
+          assert_equal :restrict, fk.on_delete
+        end
+      end
+
+      def test_add_on_delete_cascade_foreign_key
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :cascade
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal :cascade, fk.on_delete
+      end
+
+      def test_add_on_delete_nullify_foreign_key
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal :nullify, fk.on_delete
+      end
+
+      def test_on_update_and_on_delete_raises_with_invalid_values
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :invalid
+        end
+
+        assert_raises ArgumentError do
+          @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :invalid
+        end
+      end
+
+      def test_add_foreign_key_with_on_update
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_update: :nullify
+
+        foreign_keys = @connection.foreign_keys("astronauts")
+        assert_equal 1, foreign_keys.size
+
+        fk = foreign_keys.first
+        assert_equal :nullify, fk.on_update
+      end
+
+      def test_remove_foreign_key_inferes_column
+        @connection.add_foreign_key :astronauts, :rockets
+
+        assert_equal 1, @connection.foreign_keys("astronauts").size
+        @connection.remove_foreign_key :astronauts, :rockets
+        assert_equal [], @connection.foreign_keys("astronauts")
+      end
+
+      def test_remove_foreign_key_by_column
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id"
+
+        assert_equal 1, @connection.foreign_keys("astronauts").size
+        @connection.remove_foreign_key :astronauts, column: "rocket_id"
+        assert_equal [], @connection.foreign_keys("astronauts")
+      end
+
+      def test_remove_foreign_key_by_name
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", name: "fancy_named_fk"
+
+        assert_equal 1, @connection.foreign_keys("astronauts").size
+        @connection.remove_foreign_key :astronauts, name: "fancy_named_fk"
+        assert_equal [], @connection.foreign_keys("astronauts")
+      end
+
+      def test_remove_foreign_non_existing_foreign_key_raises
+        assert_raises ArgumentError do
+          @connection.remove_foreign_key :astronauts, :rockets
+        end
+      end
+
+      def test_schema_dumping
+        @connection.add_foreign_key :astronauts, :rockets
+        output = dump_table_schema "astronauts"
+        assert_match %r{\s+add_foreign_key "astronauts", "rockets"$}, output
+      end
+
+      def test_schema_dumping_with_options
+        output = dump_table_schema "fk_test_has_fk"
+        assert_match %r{\s+add_foreign_key "fk_test_has_fk", "fk_test_has_pk", column: "fk_id", primary_key: "pk_id", name: "fk_name"$}, output
+      end
+
+      def test_schema_dumping_on_delete_and_on_update_options
+        @connection.add_foreign_key :astronauts, :rockets, column: "rocket_id", on_delete: :nullify, on_update: :cascade
+
+        output = dump_table_schema "astronauts"
+        assert_match %r{\s+add_foreign_key "astronauts",.+on_update: :cascade,.+on_delete: :nullify$}, output
+      end
+
+      class CreateCitiesAndHousesMigration < ActiveRecord::Migration
+        def change
+          create_table("cities") { |t| }
+
+          create_table("houses") do |t|
+            t.column :city_id, :integer
+          end
+          add_foreign_key :houses, :cities, column: "city_id"
+        end
+      end
+
+      def test_add_foreign_key_is_reversible
+        migration = CreateCitiesAndHousesMigration.new
+        silence_stream($stdout) { migration.migrate(:up) }
+        assert_equal 1, @connection.foreign_keys("houses").size
+      ensure
+        silence_stream($stdout) { migration.migrate(:down) }
+      end
+    end
+  end
+end
+else
+module ActiveRecord
+  class Migration
+    class NoForeignKeySupportTest < ActiveRecord::TestCase
+      setup do
+        @connection = ActiveRecord::Base.connection
+      end
+
+      def test_add_foreign_key_should_be_noop
+        @connection.add_foreign_key :clubs, :categories
+      end
+
+      def test_remove_foreign_key_should_be_noop
+        @connection.remove_foreign_key :clubs, :categories
+      end
+
+      def test_foreign_keys_should_raise_not_implemented
+        assert_raises NotImplementedError do
+          @connection.foreign_keys("clubs")
+        end
+      end
+    end
+  end
+end
+end