在 docker 中运行 crontab。 姜戈

Question

Sorry for my english. I created docker file. For cron task i user this library , In my local test all work, but now i try use docker and try run cron there.But now i have error

no crontab for root

My docker file:

FROM python:3.6

WORKDIR /usr/src/app
COPY requirements.txt ./

RUN apt-get update && apt-get install -y cron
RUN pip install -r requirements.txt

COPY . .
EXPOSE 8000

CMD python manage.py runserver 0.0.0.0:8000
RUN python manage.py crontab add
RUN python manage.py crontab show

My requirements

Django==1.11.4
django-filter==1.0.4
djangorestframework
Pillow
django-crontab

Answer 1

I recently encountered this problem while moving a Django project to the docker-compose environment.

Here's what worked for me at Nginx Unit which is based on Python3.9 (and some Ubuntu distribution):

1. Somewhere in the Dockerfile there must be cron installed and started.

    apt install cron -y

2. Then you need to start it with (i'm not sure about this step, at worst nothing will happen).

    service cron start

3. Run django crontab

    python manage.py crontab add

4. And the last step, which appears the autor doesn't have is running

   service cron restart

Answer 2

Perhaps django-crontab expects the crontab to exist before adding stuff. You can try to create a new crontab for root first.

RUN crontab <<< '# new crontab'
RUN python manage.py crontab add
RUN python manage.py crontab show