Docker container not running on Linux - django

In our project we use docker to keep our development environments similar. When running it on macOS it works, however on Linux (currently using Manjaro) it states that the container doesn't exist:
docker-compose -f docker-compose.yml exec web python manage.py migrate --noinput
Error response from daemon: Container 43f405eac00706b22dc075cbcaf33dbbf595971be3ce1955034302cb1284aa5b is not running
make: *** [Makefile:9: build] Error 1
This is the makefile for our project:
build:
make down
docker-compose -f docker-compose.yml up -d --build
docker-compose -f docker-compose.yml exec web python manage.py migrate --noinput
docker-compose -f docker-compose.yml exec web python manage.py createsuperuser --noinput --email name#testmail.org
docker-compose -f docker-compose.yml exec web python manage.py startup
We tried different systems and different commands, but it always fails when trying to execute the second command.

Related

Python 3.8-alpine docker compose failing

I have been running an app without docker and have just added in Dockerfile and docker-compose.
The issue I am having is that after I successfuly build the app, runserver produces the below error when I run either that or migrate.
➜ app git:(master) sudo docker-compose run app sh -c "python manage.py runserver"
Error loading shared library libpython3.8.so.1.0: No such file or directory (needed by /usr/local/bin/python)
Error relocating /usr/local/bin/python: Py_BytesMain: symbol not found
failed to resize tty, using default size
%
➜ app git:(master) sudo docker-compose run app sh -c "python manage.py migrate"
Error loading shared library libpython3.8.so.1.0: No such file or directory (needed by /usr/local/bin/python)
Error relocating /usr/local/bin/python: Py_BytesMain: symbol not found
Dockerfile
FROM python:3.8-alpine
MAINTAINER realize-sec
ENV PYTHONUNBUFFERED 1
COPY requirements.txt /requirements.txt
RUN pip install -r requirements.txt
RUN mkdir /app
WORKDIR /app
COPY ./app /app
RUN adduser -D user
USER user
docker-compose.yml
version: "3"
services:
app:
build:
context: ""
ports:
- "8000:8000"
volumes:
- ./app:/app
command: >
sh -c "python manage.py runserver 0.0.0.0:8000"
What am I doing wrong that is causing this?
When I run without docker using python3 manage.py runserver it works fine.
Because I haven’t tested the build, I don’t know whether any of these things will help you to ultimately build your containers, however here are some observations to hopefully set you on the right path.
Your context is a null string and is usually a dot (.)
You typically finish the Dockerfile with the following command:
CMD [ "python3", "manage.py", "runserver", "0.0.0.0:8000" ]
So you can remove that from your compose file.
Other than that, on a more general note, although Alpine images are small, they are prone to breaking because of the additional dependencies and packages that you need to add/remove. You’re probably better off with going for the slim version overall. The original build will take a bit longer but it will be more manageable.
Also, if you’re running a modern version of Docker on your machine, then you can move the syntax version of the compose file to version 3.7 or 3.8, depending upon your version of Docker.

Execute migrations in production but they are not created in my server

I try to create the migrations with the command but not copy the files
sudo docker-compose -f production.yml run --rm django python manage.py makemigrations

Docker Compose ENTRYPOINT and CMD with Django Migrations

I've been trying to find the best method to handle setting up a Django project with Docker. But I'm somewhat confused as to how CMD and ENTRYPOINT function in relation to the compose commands.
When I first set the project up, I need to run createsuperuser and migrate for the database. I've tried using a script to run the commands as the entrypoint in my Dockerfile but it didn't seem to work consistently. I switched to the configuration shown below, where I overwrite the Dockerfile CMD with commands in my compose file where it is told to run makemigrations, migrate, and createsuperuser.
The issue I'm having is exactly how to set it up so that it does what I need. If I set a command (shown as commented out in the code) in my compose file it should overwrite the CMD in my Dockerfile from what I understand.
What I'm unsure of is whether or not I need to use ENTRYPOINT or CMD in my Dockerfile to achieve this? Since CMD is overwritten by my compose file and ENTRYPOINT isn't, wouldn't it cause problems if it was set to ENTRYPOINT, since it would try to run gunicorn a second time after the compose command is executed?
Would there be any drawbacks in this approach compared to using an entrypoint script?
Lastly, is there a general best practice approach to handling Django's setup commands when deploying a dockerized Django application? Or am I already doing what is typically done?
Here is my Dockerfile:
FROM python:3.6
LABEL maintainer x#x.com
ARG requirements=requirements/production.txt
ENV DJANGO_SETTINGS_MODULE=site.settings.production_test
WORKDIR /app
COPY manage.py /app/
COPY requirements/ /app/requirements/
RUN pip install -r $requirements
COPY config config
COPY site site
COPY templates templates
COPY logs logs
COPY scripts scripts
EXPOSE 8001
CMD ["/usr/local/bin/gunicorn", "--config", "config/gunicorn.conf", "--log-config", "config/logging.conf", "-e", "DJANGO_SETTINGS_MODULE=site.settings.production_test", "-w", "4", "-b", "0.0.0.0:8001", "site.wsgi:application"]
And my compose file (omitted the nginx and postgres sections as they are unnecessary to illustrate the issue):
version: "3.2"
services:
app:
restart: always
build:
context: .
dockerfile: Dockerfile.prodtest
args:
requirements: requirements/production.txt
#command: bash -c "python manage.py makemigrations && python manage.py migrate && gunicorn --config gunicorn.conf --log-config loggigng.conf -e DJANGO_SETTINGS_MODULE=site.settings.production_test -W 4 -b 0.0.0.0:8000 site.wsgi"
container_name: dj01
environment:
- DJANGO_SETTINGS_MODULE=site.settings.production_test
- PYTHONDONTWRITEBYTECODE=1
volumes:
- ./:/app
- /static:/static
- /media:/media
networks:
- main
depends_on:
- db
I have the following entrypoint script that will attempt to do the migrate automatically on my Django project:
#!/bin/bash -x
python manage.py migrate --noinput || exit 1
exec "$#"
The only change that would need to happen to your Dockerfile is to ADD it and specify the ENTRYPOINT. I usually put these lines directly about the CMD instruction:
ADD docker-entrypoint.sh /docker-entrypoint.sh
RUN chmod a+x /docker-entrypoint.sh
ENTRYPOINT ["/docker-entrypoint.sh"]
(please note that the chmod is only necessary if the docker-entrypoint.sh file on in your build environment is not executable already)
I add || exit 1 so that the script will stop the container should the migrate fail for any reason. When starting your project via docker-compose, it's possible that the database may not be 100% ready to accept connections when this migrate command runs. Between the exit on error approach and the restart: always that you have in your docker-compose.yml already, this will handle that race condition properly.
Note that the -x option I specify for bash echoes out what bash is doing, which I find helpful for debugging my scripts. It can be omitted if you want less verbosity in the container logs.
Dockerfile:
...
ENTRYPOINT ["entrypoint.sh"]
CMD ["start"]
entrypoint.sh will be executed all the time whilst CMD will be the default argument for it (docs)
entrypoint.sh:
if ["$1" = "start"]
then
/usr/local/bin/gunicorn --config config/gunicorn.conf \
--log-config config/logging.conf ...
elif ["$1" = "migrate"]
# whatever
python manage.py migrate
fi
now it is possible to do something like
version: "3.2"
services:
app:
restart: always
build:
...
command: migrate # if needed
or
docker exec -it <container> bash -c entrypoint.sh migrate

gunicorn: command not found django

Using Docker to install gunicorn, I am unable to to use the gunicorn command.
To start Django, I have this line in my docker-compose.yaml:
command: bash -c "python manage.py makemigrations && python manage.py migrate && gunicorn myproject.wsgi -b 0.0.0.0:8000"
This results in bash: gunicorn: command not found
When I build the Docker images it says gunicorn has been successfully installed.
My Dockerfile looks like:
FROM python:3.5
ENV PYTHONUNBUFFERED 1
RUN mkdir /config
ADD requirements.txt /config/
RUN pip install -r /config/requirements.txt
RUN mkdir /src;
WORKDIR /src
I've been using this http://ruddra.com/2016/08/14/docker-django-nginx-postgres/ as a guide.
If you are finding that gunicorn doesn't exist it could be because
docker image may use a cached layer of the requirements.txt which doesn't have gunicorn in it as a dependency.
Therefore it will result in not installing gunicorn meanwhile specifying pip install gunicorn in a seperate RUN command will work.
Solution:
Build docker image without caching when edits have been made to requirements.txt
docker build --no-cache .

django-cookiecutter, docker-compose run: can't type in terminal

I'm having an issue with a project started with django cookiecutter.
To verify that the issue was not with my project, I'm testing on a blank django cookiecutter project.
The issue is that when I run:
docker-compose -f production.yml run --rm django python manage.py createsuperuser
I get the prompt but can't type in the terminal.
Same thing when I run:
docker-compose -f production.yml run --rm django python manage.py shell
I get the shell prompt, but I can't type.
The app is running on a machine on DigitalOcean created with the docker-machine create command.
Any thoughts on what the issue could be and how I could debug this?
to enable typing in docker-compose terminal, you need to specify the terminal session is interactive on the docker-compose.yml. Because by default, docker console is not interactive.
stdin_open: true
tty: true
bash can be accessed inside the docker container using the following command.
docker-compose -f production.yml exec django bash
This will give you full access to the container of your django server.
There you can run all your normal django commands with full interactivity.
Create Superuser
python manage.py createsuperuser
For Local ENV
docker-compose -f local.yml exec django bash