I'm running a Flask application with a Custom Script. Or trying to, anyway.
I'm on Windows 10 and the application ought to run in a linux Docker container with the command:
docker-compose up api
Docker-compose is version 1.23.2. In the dockerfile, the api service runs via the command:
command: python manage.py run --host "0.0.0.0" --with-threads
As it tries to start up, I see the exception
OSError: [Errno 8] Exec format error: '/api/manage.py'
I initially thought this would be the Dreaded Windows Line Endings, come for me once more, but running dos2unix on all my source files has not resolved the problem.
How can I avoid this error?
manage.py
import click
from flask.cli import FlaskGroup
from my_app_api import create_app
def create_my_app(info):
return create_app()
@click.group(cls=FlaskGroup, create_app=create_my_app)
def cli():
pass
if __name__ == "__main__":
cli()
Full traceback
api_1 | Traceback (most recent call last):
api_1 | File "manage.py", line 22, in <module>
api_1 | cli()
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 764, in __call__
api_1 | return self.main(*args, **kwargs)
api_1 | File "/usr/local/lib/python3.6/site-packages/flask/cli.py", line 380, in main
api_1 | return AppGroup.main(self, *args, **kwargs)
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 717, in main
api_1 | rv = self.invoke(ctx)
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 1137, in invoke
api_1 | return _process_result(sub_ctx.command.invoke(sub_ctx))
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 956, in invoke
api_1 | return ctx.invoke(self.callback, **ctx.params)
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 555, in invoke
api_1 | return callback(*args, **kwargs)
api_1 | File "/usr/local/lib/python3.6/site-packages/click/decorators.py", line 64, in new_func
api_1 | return ctx.invoke(f, obj, *args, **kwargs)
api_1 | File "/usr/local/lib/python3.6/site-packages/click/core.py", line 555, in invoke
api_1 | return callback(*args, **kwargs)
api_1 | File "/usr/local/lib/python3.6/site-packages/flask/cli.py", line 438, in run_command
api_1 | use_debugger=debugger, threaded=with_threads)
api_1 | File "/usr/local/lib/python3.6/site-packages/werkzeug/serving.py", line 988, in run_simple
api_1 | run_with_reloader(inner, extra_files, reloader_interval, reloader_type)
api_1 | File "/usr/local/lib/python3.6/site-packages/werkzeug/_reloader.py", line 332, in run_with_reloader
api_1 | sys.exit(reloader.restart_with_reloader())
api_1 | File "/usr/local/lib/python3.6/site-packages/werkzeug/_reloader.py", line 176, in restart_with_reloader
api_1 | exit_code = subprocess.call(args, env=new_environ, close_fds=False)
api_1 | File "/usr/local/lib/python3.6/subprocess.py", line 287, in call
api_1 | with Popen(*popenargs, **kwargs) as p:
api_1 | File "/usr/local/lib/python3.6/subprocess.py", line 729, in __init__
api_1 | restore_signals, start_new_session)
api_1 | File "/usr/local/lib/python3.6/subprocess.py", line 1364, in _execute_child
api_1 | raise child_exception_type(errno_num, err_msg, err_filename)
api_1 | OSError: [Errno 8] Exec format error: '/api/manage.py'
This is a new behavior in Werkzeug 0.15. Downgrading to Werkzeug 0.14.1 may work, but 0.14 is no longer supported, so you will be better off correcting the issue with your file as described in the other answers.
The answer of @CristiFati worked for me with 1 additional step:
I also had to correct the EOL from \r\n to \n.
Sorry I don't have enough points to add a comment and have to open a new answer...
If you disable debug mode (don't pass debug=True or set FLASK_DEBUG=0), the reloader will not be used and so this issue will not happen. The tradeoff is that you no longer have the reloader.
if __name__ == "__main__":
connexion_app.run(host="0.0.0.0", port=constants.API_PORT, debug=True)
It is preferrable to fix this by ensuring files marked as executable have an interpreter line, like #!/usr/bin/env python3 (from https://stackoverflow.com/a/55272071).
Werkzeug==0.15.4 has this question。
pip install --user Werkzeug==0.16