当python应用程序尝试将日志文件写入docker中的共享卷时，权限被拒绝

Question

我正在尝试编写一个简单的python应用程序，在docker内部与非root用户一起运行，我希望将日志文件登录到共享卷中

docker-compose.yml

version: '3.7'

services:
  testapp:
    hostname: pythonapp
    container_name: pythonapp
    build:
      context: .
      dockerfile: Dockerfile
    environment:
      - TZ=Europe/Rome
    ports:
      - "8080:8080"
    volumes:
      - ./log:/home/pythonapp/src/log

docker生成文件

FROM python:3

# set environment variables
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1

# Create a user with given UID.
RUN useradd -m -u 5000 pythonapp
USER pythonapp
RUN id

RUN mkdir -p /home/pythonapp/src/log
RUN chown -R pythonapp:pythonapp /home/pythonapp 
WORKDIR /home/pythonapp/src

## copy from host to container files
COPY --chown=pythonapp:pythonapp . .

## install dependencies
RUN pip install --user --upgrade pip
RUN pip install --user -r requirements.txt

CMD ["python", "/home/pythonapp/src/pythonapp.py", "-p", "8080"]

在构建映像之前，我在主机macchine中创建了日志文件夹

mkdir log
ls -la
>>> drwxrwxr-x 2 tabita tabita 4096 ott  2 19:16 log

setfacl -m u:5000:rwx ./log

ls -la
>>> drwxrwxr-x+ 2 tabita tabita 4096 ott  2 19:16 log

getfacl log/
>>># file: log/
# owner: tabita
# group: tabita
user::rwx
user:5000:rw-
group::rwx
mask::rwx
other::r-x

然后我用docker compose创建了这个图像

docker-compose -f docker-compose.yml up --build -v

然而，我在这里得到了错误

pythonapp | /home/pythonapp/src
pythonapp | pythonapp
pythonapp | uid=5000(pythonapp) gid=5000(pythonapp) groups=5000(pythonapp)
pythonapp | Traceback (most recent call last):
pythonapp |   File "/home/pythonapp/src/ssh_honeypot.py", line 28, in <module>
pythonapp |     logging.basicConfig(
pythonapp |   File "/usr/local/lib/python3.9/logging/__init__.py", line 2003, in basicConfig
pythonapp |     h = FileHandler(filename, mode,
pythonapp |   File "/usr/local/lib/python3.9/logging/__init__.py", line 1146, in __init__
pythonapp |     StreamHandler.__init__(self, self._open())
pythonapp |   File "/usr/local/lib/python3.9/logging/__init__.py", line 1175, in _open
pythonapp |     return open(self.baseFilename, self.mode, encoding=self.encoding,
pythonapp | PermissionError: [Errno 13] Permission denied: '/home/pythonapp/src/log/pythonapp.log'
pythonapp exited with code 1

调试

我试图进入容器并在日志文件夹中创建一个文件。我可以创建一个，但从主机系统看不到创建的文件

你能帮帮我吗

Answer 1

我已使用此脚本尝试了您的文件：

# pythonapp.py
with open('/home/pythonapp/src/log/test.txt', 'w') as f:
    f.write("Hello world!")

只有当x访问权被授予用户5000时，它才能很好地工作

通过日志目录需要此权限

关于您的输出，权限当前为rw-

getfacl log/
>>># file: log/
...
user:5000:rw-
...

由于您的程序似乎很精确，您能否从以下位置重试：

log is under my working directory

1. 为具有UID:5000的用户添加权限：

   setfacl -m u:5000:rwx log
   

2. 检查权限，rwx是必需的

   I think tabular is a good option to view ACL permissions

   getfacl  tabular log 
   # file: log
   USER   <myuser>  rwx     
   user   5000      rwx     
   GROUP  <myuser>  rwx     
   mask             rwx     
   other            r-x  
   

3. pythonapp.py应该能够在日志目录下写入：

   docker-compose up build

   Step 13/13 : CMD ["python", "/home/pythonapp/src/pythonapp.py", "-p", "8080"]
     -> Using cache
    -> fcd2afb9f961
   Successfully built fcd2afb9f961
   Successfully tagged so_testapp:latest
   Starting pythonapp ... done
   Attaching to pythonapp
   pythonapp exited with code 0