kaxil opened a new pull request, #55443: URL: https://github.com/apache/airflow/pull/55443
Final blocker for 3.1.0b1 The `airflow scheduler` fails to start with this error when the logs directory doesn't exist: ``` RuntimeError: Directory '/root/airflow/logs' does not exist ``` This regression was introduced in [#52581](https://github.com/apache/airflow/pull/52581) when serve_logs was refactored from Flask to FastAPI. **Module Import Order Dependency**: FastAPI's `StaticFiles` validates directory existence at app creation time, but this happens at **module import time** before Airflow's initialization sequence: ```python uvicorn.run("airflow.utils.serve_logs.log_server:app") # imports module ↓ app = create_app() # runs immediately at module level ↓ StaticFiles(directory=log_directory) # FAILS: directory doesn't exist yet ``` **Expected initialization order**: ``` settings.initialize() → configure_logging() → init_log_folder() → create_app() ``` **Actual order with eager loading**: ``` import log_server → create_app() → FAIL (directory doesn't exist) ``` --- Without this fix, we see following error when running `airflow standalone` fresh in an isolated container: Error 1: ``` scheduler | Traceback (most recent call last): scheduler | File "/.venv/bin/airflow", line 10, in <module> scheduler | sys.exit(main()) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/__main__.py", line 55, in main scheduler | args.func(args) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/cli_config.py", line 49, in command scheduler | return func(*args, **kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/cli.py", line 114, in wrapper scheduler | return f(*args, **kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/providers_configuration_loader.py", line 54, in wrapped_function scheduler | return func(*args, **kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/commands/scheduler_command.py", line 52, in scheduler scheduler | run_command_with_daemon_option( scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/commands/daemon_utils.py", line 86, in run_command_with_daemon_option scheduler | callback() scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/commands/scheduler_command.py", line 55, in <lambda> scheduler | callback=lambda: _run_scheduler_job(args), scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/commands/scheduler_command.py", line 42, in _run_scheduler_job scheduler | with _serve_logs(args.skip_serve_logs), _serve_health_check(enable_health_check): scheduler | File "/usr/local/lib/python3.10/contextlib.py", line 135, in __enter__ scheduler | return next(self.gen) scheduler | File "/.venv/lib/python3.10/site-packages/airflow/cli/commands/scheduler_command.py", line 62, in _serve_logs scheduler | from airflow.utils.serve_logs import serve_logs scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/serve_logs/__init__.py", line 20, in <module> scheduler | from airflow.utils.serve_logs.log_server import create_app scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/serve_logs/log_server.py", line 160, in <module> scheduler | app = create_app() scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/serve_logs/log_server.py", line 153, in create_app scheduler | JWTAuthStaticFiles(directory=log_directory, html=False), scheduler | File "/.venv/lib/python3.10/site-packages/airflow/utils/serve_logs/log_server.py", line 49, in __init__ scheduler | super().__init__(*args, **kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/starlette/staticfiles.py", line 56, in __init__ scheduler | raise RuntimeError(f"Directory '{directory}' does not exist") scheduler | RuntimeError: Directory '/root/airflow/logs' does not exist ``` Error 2: This was because we had harcoded 2 workers! but this isn't needed ``` scheduler | Process SpawnProcess-1:53: scheduler | Traceback (most recent call last): scheduler | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap scheduler | self.run() scheduler | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 108, in run scheduler | self._target(*self._args, **self._kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/uvicorn/_subprocess.py", line 73, in subprocess_started scheduler | sys.stdin = os.fdopen(stdin_fileno) # pragma: full coverage scheduler | File "/usr/local/lib/python3.10/os.py", line 1030, in fdopen scheduler | return io.open(fd, mode, buffering, encoding, *args, **kwargs) scheduler | OSError: [Errno 9] Bad file descriptor scheduler | Process SpawnProcess-1:54: scheduler | Traceback (most recent call last): scheduler | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap scheduler | self.run() scheduler | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 108, in run scheduler | self._target(*self._args, **self._kwargs) scheduler | File "/.venv/lib/python3.10/site-packages/uvicorn/_subprocess.py", line 73, in subprocess_started scheduler | sys.stdin = os.fdopen(stdin_fileno) # pragma: full coverage scheduler | File "/usr/local/lib/python3.10/os.py", line 1030, in fdopen scheduler | return io.open(fd, mode, buffering, encoding, *args, **kwargs) scheduler | OSError: [Errno 9] Bad file descriptor triggerer | Process SpawnProcess-1:53: triggerer | Traceback (most recent call last): triggerer | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 314, in _bootstrap triggerer | self.run() triggerer | File "/usr/local/lib/python3.10/multiprocessing/process.py", line 108, in run triggerer | self._target(*self._args, **self._kwargs) triggerer | File "/.venv/lib/python3.10/site-packages/uvicorn/_subprocess.py", line 73, in subprocess_started triggerer | sys.stdin = os.fdopen(stdin_fileno) # pragma: full coverage triggerer | File "/usr/local/lib/python3.10/os.py", line 1030, in fdopen triggerer | return io.open(fd, mode, buffering, encoding, *args, **kwargs) triggerer | OSError: [Errno 9] Bad file descriptor ``` This implementation follows the same pattern as Airflow's main API: | Component | Pattern | File | |-----------|---------|------| | **Main API** | `cached_app()` with global caching | `api_fastapi/app.py` | | **serve_logs** | `get_app()` with global caching | `utils/serve_logs/log_server.py` | Both use lazy initialization with global app caching, ensuring proper startup order while maintaining performance. --- **Fixes**: Scheduler startup failures with LocalExecutor **Related-to**: d8a3ad24df5ae363b7dee3441fac1b4c8df85c3a <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!-- Thank you for contributing! Please make sure that your code changes are covered with tests. And in case of new features or big changes remember to adjust the documentation. Feel free to ping committers for the review! In case of an existing issue, reference it using one of the following: closes: #ISSUE related: #ISSUE How to write a good git commit message: http://chris.beams.io/posts/git-commit/ --> <!-- Please keep an empty line above the dashes. --> --- **^ Add meaningful description above** Read the **[Pull Request Guidelines](https://github.com/apache/airflow/blob/main/contributing-docs/05_pull_requests.rst#pull-request-guidelines)** for more information. In case of fundamental code changes, an Airflow Improvement Proposal ([AIP](https://cwiki.apache.org/confluence/display/AIRFLOW/Airflow+Improvement+Proposals)) is needed. In case of a new dependency, check compliance with the [ASF 3rd Party License Policy](https://www.apache.org/legal/resolved.html#category-x). In case of backwards incompatible changes please leave a note in a newsfragment file, named `{pr_number}.significant.rst` or `{issue_number}.significant.rst`, in [airflow-core/newsfragments](https://github.com/apache/airflow/tree/main/airflow-core/newsfragments). -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
