Docker-Compose部署Django+Redis+Celery报错：celery不在$PATH中

尝试用docker-compose部署Django+Redis+Celery项目时，Celery容器启动失败，报错exec: "celery": executable file not found in $PATH。

docker-compose.yml 内容 #

version: "3.9"

services:
  db: 
    container_name: my_table_postgres
    image: postgres
    ports:
      - 5432/tcp
    volumes:
      - my_table_postgres_db:/var/lib/postgresql/data
    environment:
      - POSTGRES_DB=my_table_postgres
      - POSTGRES_USER=dev
      - POSTGRES_PASSWORD=Ieyh5&RIR48!&8fc

  redis: 
    container_name: redis
    image: redis

  my_table:
    container_name: my_table
    build: .
    command: python manage.py runserver 0.0.0.0:5000
    volumes:
      - .:/api
    ports:
      - "5000:5000"
    depends_on:
      - db
      - redis

  celery:
    restart: always
    build:
      context: .
    command: ['celery', '-A', 'mytable', '-l', 'INFO']
    volumes:
      - .:/api
    container_name: celery
    depends_on:
      - db
      - redis
      - my_table

volumes:
  my_table_postgres_db:
  redis_data:

Dockerfile 内容 #

FROM python:3.11

# Managing user
RUN mkdir /mytable
RUN useradd -ms /bin/bash devuser
USER devuser
COPY . /mytable
WORKDIR /mytable

# Keeps Python from generating .pyc files in the container
ENV PYTHONDONTWRITEBYTECODE=1

# Turns off buffering for easier container logging
ENV PYTHONUNBUFFERED=1

COPY --chown=devuser:devuser requirements.txt requirements.txt
RUN pip install --user --default-timeout=1000 --upgrade pip
RUN pip install --user --default-timeout=1000 -r requirements.txt

EXPOSE 5000

#ENV PATH="/home/devuser/.local/bin"

COPY --chown=devuser:devuser . .

# Run manage.py runserver when the container launches
CMD ["python3", "manage.py", "runserver"]

错误信息 #

Recreating eda7aad3f246_celery ... error

ERROR: for eda7aad3f246_celery  Cannot start service celery: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: exec: "celery": executable file not found in $PATH: unknown

ERROR: for celery  Cannot start service celery: failed to create shim task: OCI runtime create failed: runc create failed: unable to start container process: exec: "celery": executable file not found in $PATH: unknown        
ERROR: Encountered errors while bringing up the project.

问题根源是使用pip install --user安装Celery后，其可执行文件位于/home/devuser/.local/bin目录，但该目录未被加入系统$PATH，导致容器无法找到celery命令。可通过以下两种方式解决：

方法1：开启Dockerfile中的PATH环境变量配置 #

取消Dockerfile中该行的注释，将Celery所在目录加入环境变量：

ENV PATH="/home/devuser/.local/bin:$PATH"

方法2：直接使用Celery的绝对路径执行 #

在docker-compose.yml的celery服务中，修改command为绝对路径：

command: ['/home/devuser/.local/bin/celery', '-A', 'mytable', '-l', 'INFO']

额外优化建议 #

• my_table服务的卷挂载路径./api与Dockerfile中的工作目录/mytable不一致，建议统一为- .:/mytable，避免代码加载异常。
• Celery服务无需依赖my_table，可移除depends_on中的my_table项，简化启动依赖。

内容的提问来源于stack exchange，提问作者Matteo Possamai