Importing correct MySqlContext in test_generic_transfer

[amoghrajesh]

Saw this failure in CI:

  __________________ TestMySql.test_mysql_to_mysql[mysqlclient] __________________
  
  self = <provider_tests.standard.operators.test_generic_transfer.TestMySql object at 0x7f4af01daa30>
  client = 'mysqlclient'
  
      @pytest.mark.parametrize(
          "client",
          [
              "mysqlclient",
              "mysql-connector-python",
          ],
      )
      def test_mysql_to_mysql(self, client):
  >       from providers.tests.mysql.hooks.test_mysql import MySqlContext
  E       ModuleNotFoundError: No module named 'providers.tests.mysql'
  
  providers/standard/tests/provider_tests/standard/operators/test_generic_transfer.py:68: ModuleNotFoundError
  --------------------------- Captured stdout teardown ---------------------------
  [2025-01-29T15:34:23.806+0000] {base.py:65} INFO - Retrieving connection 'mysql_default'
  ---------------------------- Captured log teardown -----------------------------
  INFO     airflow.hooks.base:base.py:65 Retrieving connection 'mysql_default'
  ____________ TestMySql.test_mysql_to_mysql[mysql-connector-python] _____________
  
  self = <provider_tests.standard.operators.test_generic_transfer.TestMySql object at 0x7f4af01daaf0>
  client = 'mysql-connector-python'
  
      @pytest.mark.parametrize(
          "client",
          [
              "mysqlclient",
              "mysql-connector-python",
          ],
      )
      def test_mysql_to_mysql(self, client):
  >       from providers.tests.mysql.hooks.test_mysql import MySqlContext
  E       ModuleNotFoundError: No module named 'providers.tests.mysql'
  
  providers/standard/tests/provider_tests/standard/operators/test_generic_transfer.py:68: ModuleNotFoundError

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[potiuk]

I think proper fix will be copy&paste the MySQL context here. We are not supposed to import test code between providers - their test code should be rather independent.

We could potentially move the context to tests_common - because this is where providers import common code from, but I think in this case. just copying the context manager here will be a better solution - both MySQL tests and Generic tests here are testing MySQL Hooks in similar way, but keeping DRY in tests is not really a goal, tests are generally better if they are "standalone" - even if some code is copied.

[amoghrajesh]

I think proper fix will be copy&paste the MySQL context here. We are not supposed to import test code between providers - their test code should be rather independent.

Yeah makes sense. I was too sleepy to think straight :D!

[amoghrajesh]

    class MySqlContext:
        def __init__(self, client):
            self.client = client
            self.connection = MySqlHook.get_connection(MySqlHook.default_conn_name)
            self.init_client = self.connection.extra_dejson.get("client", "mysqlclient")

        def __enter__(self):
            self.connection.set_extra(f'{{"client": "{self.client}"}}')

        def __exit__(self, exc_type, exc_val, exc_tb):
            self.connection.set_extra(f'{{"client": "{self.init_client}"}}')

This however has a MySqlHook. And even if i move that to tests_common, it will still need importing it correct?

Even prior to my change, we imported the MysqlHook, just from different path @potiuk

[potiuk]

MysqlHook is fine. All the providers are properly acceessible cross providers. It's the "test" code that is not accessible. see #46274

[amoghrajesh]

tests_common should be a better thing to do however, moved it and changed the refs

[potiuk]

I am not sure. Tests_common - should contain only "provider-agnostic code" i.e. something that does not belong to any provider. By Adding MySQL there, we make common code (which should be used by the provider tests - i.e. be dependnecy of the provider tests) into something that is USING mysql provider. So if mysql provider uses "tests_common" and "test_commmon" use mysql provider, this is "almost a cycle" it only works because provider does not use tests code - it's used by the test code..

I think I prefere copying the contextmanager in both places.

[amoghrajesh]

Yeah thanks for the clarification. That was my initial thought too.

Why to create an unwanted dependency. Anyways, ill approve your PR and you can close this one

[amoghrajesh]

Closing in favour of #46274