Add config to disable schema dump after migration

* Add a config on Active Record named `dump_schema_after_migration`
* Schema dump doesn't happen if the config is set to false
* Set default value of the config to true
* Set config in generated production environment file to false
* Update configuration guide
* Update CHANGELOG

4 files changed, 60 insertions, 0 deletions

diff --git a/railties/CHANGELOG.md b/railties/CHANGELOG.md
index 4ac6a99662..7aeabf735f 100644
--- a/railties/CHANGELOG.md
+++ b/railties/CHANGELOG.md
@@ -1,3 +1,10 @@
+*   Set `dump_schema_after_migration` config values in production.
+
+    Set `config.active_record.dump_schema_after_migration` as false
+    in the generated `config/environments/production.rb` file.
+
+    *Emil Soman*
+
 *   Added Thor-action for creation of migrations.
 
     Fixes #13588 and #12674.
diff --git a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
index d2f041aa27..d9cc60d656 100644
--- a/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
+++ b/railties/lib/rails/generators/rails/app/templates/config/environments/production.rb.tt
@@ -81,4 +81,9 @@ Rails.application.configure do
 
   # Use default logging formatter so that PID and timestamp are not suppressed.
   config.log_formatter = ::Logger::Formatter.new
+  <%- unless options.skip_active_record? -%>
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+  <%- end -%>
 end
diff --git a/railties/test/application/configuration_test.rb b/railties/test/application/configuration_test.rb
index 02d8b2c91d..b814479540 100644
--- a/railties/test/application/configuration_test.rb
+++ b/railties/test/application/configuration_test.rb
@@ -781,5 +781,22 @@ module ApplicationTests
       assert_not Rails.configuration.respond_to?(:method_missing)
       assert Rails.configuration.respond_to?(:method_missing, true)
     end
+
+    test "config.active_record.dump_schema_after_migration is false on production" do
+      build_app
+      ENV["RAILS_ENV"] = "production"
+
+      require "#{app_path}/config/environment"
+
+      assert_not ActiveRecord::Base.dump_schema_after_migration
+    end
+
+    test "config.active_record.dump_schema_after_migration is true by default on development" do
+      ENV["RAILS_ENV"] = "development"
+
+      require "#{app_path}/config/environment"
+
+      assert ActiveRecord::Base.dump_schema_after_migration
+    end
   end
 end
diff --git a/railties/test/application/rake/migrations_test.rb b/railties/test/application/rake/migrations_test.rb
index 33c753868c..b7fd5d02c5 100644
--- a/railties/test/application/rake/migrations_test.rb
+++ b/railties/test/application/rake/migrations_test.rb
@@ -153,6 +153,37 @@ module ApplicationTests
            assert_match(/up\s+\d{3,}\s+Add email to users/, output)
         end
       end
+
+      test 'schema generation when dump_schema_after_migration is set' do
+        add_to_config('config.active_record.dump_schema_after_migration = false')
+
+        Dir.chdir(app_path) do
+          `rails generate model book title:string;
+           bundle exec rake db:migrate`
+
+          assert !File.exist?("db/schema.rb")
+        end
+
+        add_to_config('config.active_record.dump_schema_after_migration = true')
+
+        Dir.chdir(app_path) do
+          `rails generate model author name:string;
+           bundle exec rake db:migrate`
+
+          structure_dump = File.read("db/schema.rb")
+          assert_match(/create_table "authors"/, structure_dump)
+        end
+      end
+
+      test 'default schema generation after migration' do
+        Dir.chdir(app_path) do
+          `rails generate model book title:string;
+           bundle exec rake db:migrate`
+
+          structure_dump = File.read("db/schema.rb")
+          assert_match(/create_table "books"/, structure_dump)
+        end
+      end
     end
   end
 end