DOCKER: Docker/Django/Travis/Heroku quickstart quide.

Docker/Django/Travis/Heroku quickstart quide.

Install Docker

Install 'Docker' as in docs (https://docs.docker.com/linux/step_one/):

curl -fsSL https://get.docker.com/ | sh

To run without sudo:

sudo usermod -aG docker `whoami`

Get docker Django image:

docker pull django

Useful docker commands

View all containers:

docker ps --all

Run docker

Get to bash console:

docker run --rm -it django /bin/bash

Get postgres console:

docker run -it --rm --link some-postgres:postgres postgres psql -h postgres -U postgres

Remove containers and images:

docker ps -f 'status=exited' -q | xargs docker rm
docker images -f dangling=true -q | xargs docker rmi

Start Django project

Create django project:

docker run django django-admin.py startproject <projectname>

Docker compose

Install docker compose

sudo pip install docker-compose

Create project dir
In this dir create Dockerfile, requirements.txt and docker-compose.yml
Dockerfile

FROM django:latest

ENV PYTHONUNBUFFERED 1
RUN mkdir /code
WORKDIR /code
ADD requirements.txt /code/
RUN pip install -r requirements.txt

requirements.txt

Django
psycopg2

docker-compose.yml

version: "2"
services:
  db:
    image: "postgres"
    volumes:
      - "pg_data:/var/lib/postgresql/data"

  web:
    build: "."
    user: "1000:1000"
    volumes:
      - ".:/code"
    ports:
      - "8000:8000"
    links:
      - "db"

volumes:
  pg_data:

Create new Django project:

docker-compose run --rm web django-admin.py startproject <projectname> .
sudo chown -R $USER:$USER .

settings.local.py

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql_psycopg2',
        'NAME': 'postgres',
        'USER': 'postgres',
        'HOST': 'db',
        'PORT': 5432,
    }
}

Docker compose useful commands

To rebuild image:

docker-compose build

docker-compose up --build

Run docker compose:

docker-compose up

Create app:

docker-compose run --rm web python manage.py startapp <app_name>

Run tests:

docker-compose run web python manage.py test

Run migrations:

docker-compose run --rm web python manage.py migrate --settings=<projectname>.settings.local

Run webserver:

docker-compose run --rm -p 8000:8000 web python manage.py runserver 0.0.0.0:8000

Setup Heroku

wget -O- https://toolbelt.heroku.com/install-ubuntu.sh | sh
heroku login
heroku ps:scale web=1 --app <heroku_app_name>
heroku config:set DJANGO_SETTINGS_MODULE=settings.heroku

wsgi.py

import os

from django.core.wsgi import get_wsgi_application
from whitenoise.django import DjangoWhiteNoise

os.environ.setdefault("DJANGO_SETTINGS_MODULE", "<projectname>.settings.heroku")

application = get_wsgi_application()
application = DjangoWhiteNoise(application)

Procfile

web: gunicorn <projectname>.wsgi --log-file -

runtime.txt

python-3.5.1

settings.heroku.py

import dj_database_url

from .base import *

DEBUG = False
TEMPLATE_DEBUG = DEBUG

ADMINS = [('user', 'user@gmail.com')]

DATABASES['default'] = dj_database_url.config()

STATICFILES_STORAGE = 'whitenoise.django.GzipManifestStaticFilesStorage'
STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')
STATIC_URL = '/static/'

ALLOWED_HOSTS = [".herokuapp.com", ]

Run migrations on heroku:

heroku run --app <heroku_app_name> python manage.py showmigrations --settings=<projectname>.settings.heroku
heroku run --app <heroku_app_name> python manage.py migrate --settings=<projectname>.settings.heroku

Setup Travis

settings.travis.py

from .base import *


if 'TRAVIS' in os.environ:
    DATABASES = {
        'default': {
            'ENGINE': 'django.db.backends.postgresql_psycopg2',
            'NAME': 'postgres',
            'USER': 'postgres',
            'HOST': 'localhost',
            'PORT': 5432,
        }
    }