text: import pytest
  
  from meltano.api.models import db
  
  
  class TestApp:
      @pytest.fixture
      def session(self):
          # disable the `session` fixture not to override
          # the `db.session`
          pass
  
      def test_core_registered(self, engine_sessionmaker, app):
          engine, _ = engine_sessionmaker
  
          # ensure both the API and the meltano.core
          # are on the same database
          assert engine.url == db.engine.url
  
  
  class TestAppSMTPDefault:
      DEFAULTS = {
          "MAIL_SERVER": "localhost",
          "MAIL_PORT": 1025,
          "MAIL_DEFAULT_SENDER": '"Meltano" <bot@meltano.com>',
          "MAIL_USE_TLS": False,
          "MAIL_USERNAME": None,
          "MAIL_PASSWORD": None,
          "MAIL_DEBUG": False,
      }
  
      def test_config_smtp_default(self, app):
          # ensure it is the defaults when not set
          assert self.DEFAULTS.items() <= app.config.items()
  
  
  class TestAppSMTP:
      ENV = {
          "MELTANO_MAIL_SERVER": "smtp.localdomain",
          "MELTANO_MAIL_PORT": "1337",
          "MELTANO_MAIL_DEFAULT_SENDER": '"Doctor Who" <dr.who@localdomain.com>',
          "MELTANO_MAIL_USE_TLS": "1",
          "MELTANO_MAIL_USERNAME": "username",
          "MELTANO_MAIL_PASSWORD": "password",
          "MELTANO_MAIL_DEBUG": "0",
      }
  
      EXPECTED = {
          "MAIL_SERVER": "smtp.localdomain",
          "MAIL_PORT": 1337,
          "MAIL_DEFAULT_SENDER": '"Doctor Who" <dr.who@localdomain.com>',
          "MAIL_USE_TLS": True,
          "MAIL_USERNAME": "username",
          "MAIL_PASSWORD": "password",
          "MAIL_DEBUG": False,
      }
  
      @pytest.fixture
      def app(self, create_app, monkeypatch):
          # ensure the environment is properly loaded
          for env, value in self.ENV.items():
              monkeypatch.setenv(env, value)
  
          return create_app()
  
      def test_config_smtp(self, app):
          assert self.EXPECTED.items() <= app.config.items()
  