Cannot Run Apache Airflow Unit Tests: sqlalchemy.exc.OperationalError: unable to open database file I am attempting to run a single unit test within the Apache Airflow repository (airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py) for development purposes. I have followed the recommended setup steps, but the test consistently fails with 2 different errors (Windows/linux). Windows (long but trimmed): (.venv) PS C:\Users\Mido Hany\VS code Projects\Habitat\airflow> pytest .\airflow-core\tests\unit\models\test_safe_exponential_backoff__HABITAT.py -q Refreshed 97 providers with 1937 Python files. Traceback (most recent call last): File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\scripts\ci\pre_commit\update_providers_dependencies.py", line 188, in <module> check_if_different_provider_used(file) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^ File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\scripts\ci\pre_commit\update_providers_dependencies.py", line 157, in check_if_different_provider_used imports = get_imports_from_file(file_path, only_top_level=False) File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\scripts\ci\pre_commit\common_precommit_utils.py", line 379, in get_imports_from_file root = ast.parse(file_path.read_text(), file_path.name) ~~~~~~~~~~~~~~~~~~~^^ File "C:\Users\Mido Hany\AppData\Local\Programs\Python\Python313\Lib\pathlib\_local.py", line 546, in read_text return PathBase.read_text(self, encoding, errors, newline) ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Mido Hany\AppData\Local\Programs\Python\Python313\Lib\pathlib\_abc.py", line 633, in read_text return f.read() ~~~~~~^^ File "C:\Users\Mido Hany\AppData\Local\Programs\Python\Python313\Lib\encodings\cp1252.py", line 23, in decode return codecs.charmap_decode(input,self.errors,decoding_table)[0] ~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 2148: character maps to <undefined> Traceback (most recent call last): File "<frozen runpy>", line 198, in _run_module_as_main File "<frozen runpy>", line 88, in _run_code File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\.venv\Scripts\pytest.exe\__main__.py", line 6, in <module> sys.exit(console_main()) ~~~~~~~~~~~~^^ ... File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\.venv\Lib\site-packages\_pytest\config\__init__.py", line 876, in import_plugin __import__(importspec) ~~~~~~~~~~^^^^^^^^^^^^ File "<frozen importlib._bootstrap>", line 1360, in _find_and_load File "<frozen importlib._bootstrap>", line 1331, in _find_and_load_unlocked File "<frozen importlib._bootstrap>", line 935, in _load_unlocked File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\.venv\Lib\site-packages\_pytest\assertion\rewrite.py", line 197, in exec_module exec(co, module.__dict__) ~~~~^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Mido Hany\VS code Projects\Habitat\airflow\devel-common\src\tests_common\pytest_plugin.py", line 200, in <module> subprocess.check_call(["uv", "run", UPDATE_PROVIDER_DEPENDENCIES_SCRIPT.as_posix()]) ~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\Mido Hany\AppData\Local\Programs\Python\Python313\Lib\subprocess.py", line 419, in check_call raise CalledProcessError(retcode, cmd) subprocess.CalledProcessError: Command '['uv', 'run', 'C:/Users/Mido Hany/VS code Projects/Habitat/airflow/scripts/ci/pre_commit/update_providers_dependencies.py']' returned non-zero exit status 1. I tried on a clean Ubuntu VM on Google Cloud, and had another error (very long but trimmed): pytest airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py -q ============================================= test session starts ============================================== platform linux -- Python 3.11.2, pytest-9.0.1, pluggy-1.6.0 -- /home/midohany910/habitat/airflow/.venv/bin/python3 cachedir: .pytest_cache rootdir: /home/midohany910/habitat/airflow configfile: pyproject.toml plugins: asyncio-1.3.0, anyio-4.12.0, time-machine-3.1.0 asyncio: mode=Mode.STRICT, debug=False, asyncio_default_fixture_loop_scope=function, asyncio_default_test_loop_scope=function collected 4 items airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_overflow_caps_to_configured_max__HABITAT ERROR [ 25%] airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_overflow_caps_to_internal_max__HABITAT ERROR [ 50%] airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_non_exponential_policy_unchanged__HABITAT ERROR [ 75%] airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_small_interval_large_attempts_overflow__HABITAT ERROR [100%] ==================================================== ERRORS ==================================================== _______________________ ERROR at setup of test_overflow_caps_to_configured_max__HABITAT ________________________ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:143: in __init__ self._dbapi_connection = engine.raw_connection() ^^^^^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:3301: in raw_connection return self.pool.connect() ^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/pool/base.py:447: in connect return _ConnectionFairy._checkout(self) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ... .venv/lib/python3.11/site-packages/sqlalchemy/engine/default.py:629: in connect return self.loaded_dbapi.connect(*cargs, **cparams) # type: ignore[no-any-return] # NOQA: E501 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file E (Background on this error at: https://sqlalche.me/e/20/e3q8) -------------------------------------------- Captured stdout setup --------------------------------------------- ========================= AIRFLOW ========================== Home of the user: /home/midohany910 Airflow home /home/midohany910/airflow Initializing the DB - first time after entering the container. Initialization can be also forced by adding --with-db-init flag when running tests. [2025-11-30T20:05:55.919+0000] {db.py:1146} INFO - Dropping Airflow tables that exist ---------------------------------------------- Captured log setup ---------------------------------------------- INFO airflow.utils.db:db.py:1146 Dropping Airflow tables that exist ________________________ ERROR at setup of test_overflow_caps_to_internal_max__HABITAT _________________________ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:143: in __init__ self._dbapi_connection = engine.raw_connection() ^^^^^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:3301: in raw_connection return self.pool.connect() ^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/pool/base.py:447: in connect return _ConnectionFairy._checkout(self) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ... .venv/lib/python3.11/site-packages/sqlalchemy/engine/create.py:661: in connect return dialect.connect(*cargs, **cparams) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/engine/default.py:629: in connect return self.loaded_dbapi.connect(*cargs, **cparams) # type: ignore[no-any-return] # NOQA: E501 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file E (Background on this error at: https://sqlalche.me/e/20/e3q8) _______________________ ERROR at setup of test_non_exponential_policy_unchanged__HABITAT _______________________ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:143: in __init__ self._dbapi_connection = engine.raw_connection() ^^^^^^^^^^^^^^^^^^^^^^^ ... .venv/lib/python3.11/site-packages/sqlalchemy/engine/create.py:661: in connect return dialect.connect(*cargs, **cparams) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/engine/default.py:629: in connect return self.loaded_dbapi.connect(*cargs, **cparams) # type: ignore[no-any-return] # NOQA: E501 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file E (Background on this error at: https://sqlalche.me/e/20/e3q8) ____________________ ERROR at setup of test_small_interval_large_attempts_overflow__HABITAT ____________________ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:143: in __init__ self._dbapi_connection = engine.raw_connection() ^^^^^^^^^^^^^^^^^^^^^^^ .venv/lib/python3.11/site-packages/sqlalchemy/engine/base.py:3301: in raw_connection return self.pool.connect() ^^^^^^^^^^^^^^^^^^^ ... .venv/lib/python3.11/site-packages/sqlalchemy/engine/default.py:629: in connect return self.loaded_dbapi.connect(*cargs, **cparams) # type: ignore[no-any-return] # NOQA: E501 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ E sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file E (Background on this error at: https://sqlalche.me/e/20/e3q8) ===================================== Warning summary. Total: 1, Unique: 1 ===================================== other: total 1, unique 1 runtest: total 1, unique 1 Warnings saved into /home/midohany910/habitat/airflow/devel-common/warnings.txt file. =========================================== short test summary info ============================================ ERROR airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_overflow_caps_to_configured_max__HABITAT - sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file ERROR airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_overflow_caps_to_internal_max__HABITAT - sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file ERROR airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_non_exponential_policy_unchanged__HABITAT - sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file ERROR airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py::test_small_interval_large_attempts_overflow__HABITAT - sqlalchemy.exc.OperationalError: (sqlite3.OperationalError) unable to open database file ========================================= 1 warning, 4 errors in 6.01s ========================================= ⚙️ Setup Steps I am running these steps from the root of the cloned Apache Airflow repository: Clone the Repository & Navigate git clone https://github.com/apache/airflow.git cd airflow Create & Activate Venv (using uv) uv venv .venv source .venv/bin/activate # Win: .venv/Scripts/activate Install Dependencies uv pip install -e ./airflow-core[devel] # Explicitly install testing tools that were missing uv pip install pytest pytest-asyncio pyyaml Set Environment Variables (Tried various versions to fix import errors) # Final working PYTHONPATH export export PYTHONPATH="./airflow-core/src:./airflow-core/tests:.:$PYTHONPATH" # Win: $envYTHONPATH = "$(Get-Location)\airflow-core\src;$(Get-Location)\airflow-core\tests;$(Get-Location)\devel-common\src" # Added the test mode flag (often required for Airflow tests) export AIRFLOWCOREUNIT_TEST_MODE="true" Run the Test pytest -q airflow-core/tests/unit/models/test_safe_exponential_backoff__HABITAT.py ❌ The Error The test session fails on windows, but starts on linux & attempts to load the test module, and then fails with the above error. What am I doing wrong?? I trimmed the errors for the post length linmit - if you need the full error I can provide. Continue reading...
