在通过docker-compose运行时，Flask CLI抛出“ OSError：[Errno 8] Exec格式错误”

Question

我正在使用自定义脚本运行Flask应用程序。还是尝试，无论如何。

我在Windows 10上，应使用以下命令在Linux Docker容器中运行应用程序：

docker-compose up api

Docker-compose是version 1.23.2。在dockerfile中，api服务通过以下命令运行：

command: python manage.py run --host "0.0.0.0" --with-threads

在尝试启动时，我看到了异常

OSError: [Errno 8] Exec format error: '/api/manage.py'

我最初以为这将是“可怕的Windows Line Ends”，再次给我，但是dos2unix在我的所有源文件上运行都无法解决问题。

如何避免此错误？

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()

全面追溯

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'

Answer 1

看起来你的api / manage.py没有shebang（[Wikipedia]：Shebang（Unix）），因此默认（当前）命令处理器（shell-通常为bash）正在尝试运行它，（显然）失败。

要解决此问题，请添加一个shebang（在文件的开头，确保你的编辑器添加了结尾为Nix样式的行（\ n，0x0A，LF））：

• 默认Python安装：

#!/usr/bin/env python

• 变体（明确指定Python 3）：

#!/usr/bin/env python3

• 自定义Python安装：

#!/full/path/to/your/custom/python/executable

请注意，你还需要对该文件（）具有执行权限chmod +x api/manage.py。

例：

[cfati@cfati-5510-0:/cygdrive/e/Work/Dev/StackOverflow/q055271912]> ~/sopr.sh
*** Set shorter prompt to better fit when pasted in StackOverflow (or other) pages ***

[prompt]> ls
code0.py  code1.py
[prompt]>
[prompt]> cat code0.py
print("This is:", __file__)

[prompt]> python3 -c "import os, subprocess;subprocess.Popen(os.path.join(os.getcwd(), \"code0.py\")).communicate()"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
OSError: [Errno 8] Exec format error: '/cygdrive/e/Work/Dev/StackOverflow/q055271912/code0.py'
[prompt]>
[prompt]> cat code1.py
#!/usr/bin/env python3

print("This is:", __file__)

[prompt]> python3 -c "import os, subprocess;subprocess.Popen(os.path.join(os.getcwd(), \"code1.py\")).communicate()"
This is: /cygdrive/e/Work/Dev/StackOverflow/q055271912/code1.py