FROM denmarkcontrevida/base:15.05
MAINTAINER Denmark Contrevida<denmarkcontrevida#esutek.com>
# Config files
# Config pyenv
# Config Nginx
# Config PostgreSQL
# Create DB & Restore database
This image will install to the newest version.
PostgreSQL
Nginx
Pyenv
Django
Python 3
IF are about to install that many different services, make sure to start from a base image made to manage them.
Use phusion/baseimage-docker (which always starts the my_init script, to take care of the zombie processes)
In that image, you can define multiple program (daemon) to run:
You only have to write a small shell script which runs your daemon, and runit will keep it up and running for you, restarting it when it crashes, etc.
The shell script must be called run, must be executable, and is to be placed in the directory /etc/service/<NAME>.
If your base image has a /etc/service/helper/run script, then any image based on it would run helper, plus any other /etc/service/xxx/run script of your own: replace xxx by the running services like nginx, django, postgresSQL.
You wouldn't need it for python3 (which is simply called, but doesn't run in the background)
Related
I am developing Django Wagtail application on my local machine connected to a local postgres server.
I have a test server and a production server.
However when I develop locally and try upload it there is always some issue with makemigration and migrate e.g. KeyError etc.
What are the best practices of ensuring I do not get run into these issues? What files do I need to port across?
so ill tell you what i do and what most of the companies that i worked as a django developer did and i can tell you by experience that worked pretty well.
First containerize your application, this will make your life much more easy and you will remove external influence in your code, also will get you an easy way to reproduce your environment.
Your Dockerfile should be from some python image and should do 3 basically things:
Install your requirements dependencies
Run the python manage.py migrate --noinput command
Run a http server such as gunicorn with gunicorn -c /gunicorn.py wsgi:application
You ill do the makemigration in your local machine and make sure that everything is working before commit then to the repo.
In your gunicorn.py you ill put your settings to run the app such as the number of CPU, the binding port, the folder that your app is, something like:
import os
import multiprocessing
# Chdir to specified directory before apps loading.
# https://docs.gunicorn.org/en/stable/settings.html#chdir
chdir = '/app/'
# Bind the application on localhost both on ipv6 and ipv4 interfaces.
# https://docs.gunicorn.org/en/stable/settings.html#bind
bind = '0.0.0.0:8000'
Second containerize your other stuff, for example the postgres database, the redis (for cache), a connection pooler for the database depending on the size of your application.
Its highly recommend that you have a step in the pipeline to do tests, they need to run before everything, maybe just after lint
Ok what now? now you need a way to deploy that stuff, the best for that scenario is: pull your image to github registry, and you can add a tag to that for example:
IMAGE_ID=ghcr.io/${{ github.repository_owner }}/$IMAGE_NAME
# Change all uppercase to lowercase
IMAGE_ID=$(echo $IMAGE_ID | tr '[A-Z]' '[a-z]')
docker tag $IMAGE_NAME $IMAGE_ID:staging
docker push $IMAGE_ID:staging
This can be add in a github action in the build step for example.
After having your new code in a new image inside github you just need to update the current one, this can be done by creaaing a script to do it in the server and running that script from github action, is something like:
docker pull ghcr.io/${{ github.repository_owner }}/$IMAGE_NAME
echo 'Restarting Application...'
docker stop {YOUR_CONTAINER} && docker up -d
sudo systemctl restart nginx
echo 'Cleaning old images'
sudo docker system prune -af
You can see that i create the image with a staging tag, you can create a rule in github actions for example to trigger that action when you create a new release for example, and create another action to be trigger in every new commit and build/deploy for a dev tag.
For the migration problem, the first thing is, when your application go live squash every migration to the first one (you can drop the database and all the migration then create the database and run the makemigration command again to reach this), so you can have a clean migration in the server. Never creates unnecessary relation between the tables, prefer always doing cached properties instead of add new columns, use UUID for unique ids, and try to not do breaking changes in the database, its hard but if you plan the database before is not so difficult to do.
Hit me if you have any questions. A lot of the stuff that i said can be done in a lot of other platforms such as gitlab, travis, circle ci, but i use the github action in the example because i think is more simple to picture.
EDIT:
I forgot to tell you to have a cron in your server doing backups of your databases, the migrate command ill apply the changes only after the verification but if something else break the database this can save your life.
I'm trying to migrate a Django application from Google Kubernetes Engine to Google Cloud Run, which is fully managed. Basically, with Cloud Run, you containerize your application into a single Dockerfile and Google does the rest.
I have a Dockerfile which at one point does call a bash script via ENTRYPOINT
But I need to start Nginx and start Gunicorn. The Google Cloud Run documentation suggest starting Gunicorn like this:
CMD gunicorn -b :$PORT foo.wsgi
(let's sat my Django app is named "foo")
But I also need to start Nginx via:
CMD ["nginx", "-g", "daemon off;"]
And since only one CMD is allowed per Dockerfile, I'm not sure how to combine them.
To try to get around some of these difficulties, I was looking into using a Dockerfile to build from that already has both working and I came across this one:
https://github.com/tiangolo/meinheld-gunicorn-docker
But the paths don't quite match mine. Quoting from the documentation of that repo:
You don't need to clone the GitHub repo. You can use this image as a
base image for other images, using this in your Dockerfile:
FROM tiangolo/meinheld-gunicorn:python3.7
COPY ./app /app It will expect a file at /app/app/main.py.
And will expect it to contain a variable app with your "WSGI"
application.
My wsgi.py file ends up at /app/foo/foo/wsgi.py and contains an application named application
But if I understand that documentation correctly, when it says it will expect the WSGI application to be named app and to be located at /app/app/main.py it's basically saying that I need to revise the path and the variable name so that when it builds the image it knows that app is called application and that instead of finding it at /app/app/main.py it will find it at /app/foo/foo/wsgi.py
I assume that I can fix the app vs application variable name by adding a line to my wsgi.py file like app = application but I'm not sure how to correct the path that Docker expects.
Can someone explain to me how to adapt this to my needs?
(Or any other way to get it working)
I am building a Python+Django development environment using docker. I defined Dockerfile files and services in docker-compose.yml for web server (nginx) and database (postgres) containers and a container that will run our app using uwsgi. Since this is a dev environment, I am mounting the the app code from the host system, so I can easily edit it in my IDE.
The question I have is where/how to run migrate command.
In case you don't know Django, migrate command creates the database structure and later changes it as needed by the project. I have seen people run migrate as part of the compose command directive command: python manage.py migrate && uwsgi --ini app.ini, but I do not want migrations to run on every container restart. I only want it to run once when I create the containers and never run again unless I rebuild.
Where/how would I do that?
Edit: there is now an open issue with the compose team. With any luck, one time command containers will get supported by compose. https://github.com/docker/compose/issues/1896
You cannot use RUN because as you mentioned in the comments your source is mounted during running of the container.
You cannot use CMD either since you don't want it to run everytime you restart the container.
I recommend using docker exec manually after running the container. I do not think there is a way to automate this inside a dockerfile or docker-compose because of the two reasons I gave above.
It sounds like what you need is a tool for managing project tasks. dobi is a tool designed to handle these tasks (disclaimer: I am the author of this tool).
You can see an example of how to run a migration here: https://github.com/dnephin/dobi/tree/master/examples/init-db-with-rails. The example uses rails, but it's basically the same idea as django.
You could setup a task called migrate which would run the command in a container and write the data to a volume. Then when you start your docker-compose containers, use that volume as the source for your database service.
https://github.com/docker/compose/issues/1896 is finally resolved now by the new service profiles introduced with docker-compose 1.28.0. With profiles you can mark services to be only started in specific profiles:
services:
nginx:
# ...
postgres:
# ...
uwsgi:
# ...
migrations:
profiles: ["cli-only"] # profile name chosen freely
# ...
docker-compose up # start only your app services, no migrations
docker-compose run migrations # run migrations on-demand
docker exec -it container-name bash
Then you will be inside the container and you can run any command you normally do when you develop without using docker.
I'm trying to find a workflow with Docker and Django. Currently, I'm using the basic configuration from the docker documentation.
I'd like to use manage.py startapp directly from the container to start a new app using:
docker-compose run web ./manage.py startapp myapp
But all the files created in the volume are owned by the root user and not by myself, so I can't edit them from the host.
My idea is to avoid installing all the requirements on my host machine but maybe I should not create app from the container?
One possible solution is to create a user and make it having the same UID/GID than my user on my host machine but it won't work if I try to use an other account on my host machine...
Any suggestion?
What worked best for me was avoiding (or minimizing) file creation inside the containers.
My Dockerfile would just copy the requirements.txt and install them;
and the container would access the app files through a mounted volume.
I pass the env var PYTHONDONTWRITEBYTECODE=1 to the containers, so python does not create *.pyc/*.pyo files.
The few times I cannot avoid it (like, ./manage.py makemigrations), I run chown afterwards.
It's not ideal, but as this happens rarely for my case, I don't bother.
We use jenkins as continious integration system. We have two django servers validated by jenkins.
jenkins validates successully the first server. The second server depends on the first one. Thus we would like to launch at the end of the first server validation the first server itself.
We are using python, virtualenv and django and defined the Virtualenv Builder as follow:
pip install -r requirements.txt
rm -f .coverage
fab localhost test
coverage xml
nohup python manage.py runserver 9090 &
The issue is that the build never ends due to the nohup.
How can I launch the server after a successful build?
I had the same problem.
Ken,
I tried using fabric, but again python manage.py runserver - runs continuosly, so the next command is not starting.
And just few mins ago my collegue showed me how to use nohup and with variable BUILD_ID of Jenkins it would be like this to get Success from the build and leave the Django server running:
BUILD_ID=dontKillMe nohup python manage.py runserver host_server &
This worked for our Django project testing.
Since you are using fabric to test, I would recommend defining another fabric task, say, deploy, which you could call assuming the build succeeds.
Much like the call to fab completes for a successful build such that you get to the nohup line, I would expect the deploy task to return also.
You may also want to consider making the server a service (either via an /etc/init.d style script, or upstart if Ubuntu), and have the fabric task stop the currently running one, copy over whatever new files it needs (or similar process), and then restart it.
Assuming what you have above is a bash script or similar, you may want to also define set -e so that, in case any of the commands returns a non-success code, the script will fail, and in turn, fail the build.