This document provides instructions for dockerizing a Django application with Postgres database. It discusses: 1) Creating a Dockerfile for the Django app and ensuring Postgres dependencies are installed. 2) Running Postgres in a container with environment variables for the database name, user, and password. 3) Configuring the Django settings to connect to the Postgres database using the environment variables. 4) Using docker-compose to define and run the Django and Postgres services on a bridge network, avoiding the need for links. The Django volume mounts the code directory for changes to be reflected.

1. raccoonyy
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raccoony @ Modern Server Lecture
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https://44bits.io / https://stdout.fm
https://raccoonyy.github.io

3. •
$ docker pull nginx

6. • git clone https://github.com/raccoonyy/
django-dockerizing
• cd django-dockerizing
• docker run --rm
-v $(pwd)/django:/usr/src/app
python:3 bash
• cd /usr/src/app
• (Windows $(pwd) %cd%)

7. .
├── Dockerfile
└── django
├── api
│ ├── apps.py
│ └── views.py
├── manage.py
├── requirements.txt
└── sample
├── settings.py
├── urls.py
└── wsgi.py

9. • pip install -r requirements.txt
• python manage.py collectstatic

10. • sample/settings.py
• DEBUG=False
DEBUG=os.environ.get('DEBUG', True)

11. • sample/settings.py
• ALLOWED_HOST = ('*', )
ALLOWED_HOST = (os.environ.get('HOST',
'*'), )

12. • sample/settings.py
• API_HOST = 'localhost:8000'
API_HOST = os.environ.get('API_HOST',
'localhost:8000')

13. • gunicorn sample.wsgi

14. • EMAIL_BACKEND
• SECRET_KEY
• ...

15. • pip install -r requirements.txt
• python manage.py collectstatic
• # sample/settings.py
DEBUG
ALLOWED_HOST
API_HOST
• gunicorn sample.wsgi

16. FROM python:3.7.3
WORKDIR /usr/src/app
COPY django ./
RUN pip install -r requirements.txt
RUN python manage.py collectstatic --noinput
CMD ["gunicorn", "sample.wsgi", "--bind=0:8000"]

17. • docker build -t docker-sample .
• docker run -it -p 8000:8000 docker-sample
• 13.125.183.70:8000/api/
• 13.125.183.70:8000/api/
database/
• 13.125.183.70:8000/api/message/

18. • Ctrl + C
$ docker ps
CONTAINER ID IMAGE ...
95bbb55fb111 docker-sample ...
$ docker kill 95bbb55fb111
$ docker rm 95bbb55fb111

21. $ docker run -d --rm -p 8000:8000
docker-sample
...
$ open localhost:8000

22. • http://IP:8000/admin/

23. $ docker exec --rm docker-sample
./manage.py migrate
$ docker exec -it --rm docker-sample
./manage.py createsuperuser
Username (leave blank to use 'root'):

24. • http://IP:8000/admin/

25. Django
8000
HOST_IP
db.sqlite3

27. $ docker kill 95bbb55fb111
$ docker run -d --rm -p 8000:8000
docker-sample
...
IP:8000

28. • http://IP:8000/admin/

29. DATABASES = {
'default': {
'ENGINE': 'django.db.backends.sqlite3',
'NAME': os.path.join(BASE_DIR, 'db.sqlite3'),
}
}
: /usr/src/app/db.sqlite3

31. $ docker ps
CONTAINER ID IMAGE ...
ABCD1234EFGH docker-sample ...
$ docker kill ABCD1234EFGH
$ docker run -d --rm -p 8000:8000
-v $(pwd)/django:/usr/src/app/
docker-sample

32. $ docker exec --rm docker-sample
./manage.py migrate
$ docker exec -it --rm docker-sample
./manage.py createsuperuser
Username (leave blank to use 'root'):

33. Django
db.sqlite3/usr/src/app/db.sqlite3

34. •
•

35. $ docker run -d --rm -p 8000:8000
-v $(pwd)/django:/usr/src/app/
docker-sample

43. # bit.ly/msl-docker-compose-install
$ sudo curl -L "https://github.com/docker/
compose/release/download/1.24.0/docker-
compose-$(uname -s)-$(uname -m)" -o /usr/
local/bin/docker-compose

44. # ~/.bashrc
alias dco='docker-compose'

45. # docker-compose.yml
version: '3'
services:
django:
image: docker-sample
ports:
- "8000:8000"
volumes:
- ./django:/usr/src/app
$ docker run -d --rm
-p 8000:8000
-v $(pwd)/django:/usr/src/app/
docker-sample

46. •
•
•
•
•
# docker-compose.yml
services:
django:
image: docker-sample
ports:
- "8000:"8000"
volumes:
- ./django:/usr/src/app

47. $ docker-compose up -d (dco up -d)
...

48. $ docker-compose down (dco down)
...

49. •
•

50. $ docker run -p 60080:80 nginx

51. version: '3'
services:
nginx:
image: nginx
ports:
- 60080:80

52. •
•
•

53. version: '3'
services:
mysql:
image: mysql

54. error: database is uninitialized and
password option is not specified
You need to specify one of
MYSQL_ROOT_PASSWORD,
MYSQL_ALLOW_EMPTY_PASSWORD and
MYSQL_RANDOM_ROOT_PASSWORD

55. version: '3'
services:
mysql:
image: mysql
environment:
- MYSQL_ROOT_PASSWORD:mypassword

56. version: '3'
services:
wordpress:
image: wordpress:latest

58. version: '3.3'
services:
db:
image: mysql:5.7
volumes:
- db_data:/var/lib/mysql
environment:
MYSQL_ROOT_PASSWORD: somewordpress
MYSQL_DATABASE: wordpress
MYSQL_USER: wordpress
MYSQL_PASSWORD: wordpress

59. wordpress:
depends_on:
- db
image: wordpress:latest
ports:
- "60000:80"
restart: always
environment:
WORDPRESS_DB_HOST: db:3306
WORDPRESS_DB_USER: wordpress
WORDPRESS_DB_PASSWORD: wordpress
WORDPRESS_DB_NAME: wordpress
volumes:
db_data: {}

60. •
•
•
•
•

61. (docker-sample )
$ docker run -d --rm postgres

62. $ docker run -d --rm postgres
2603f8e32feecb5eb0cae...
$ docker logs -f 2603f
...

63. $ docker rm -f {CONTAINER_ID}
$ docker run -d --rm -p 5432:5432 postgres

64. $ docker rm -f {CONTAINER_ID}
$ docker run -d --rm -p 5432:5432 postgres
ad45e98618531ee693cc3...
$ docker logs ad45e
...
PostgreSQL init process complete; ready for
start up.
... listening on IPv4 address "0.0.0.0",
port 5432

65. $ docker rm -f {CONTAINER_ID}
$ docker run -d --rm -p 5432:5432 postgres
ad45e98618531ee693cc3...
$ telnet 0 5432
Trying 0.0.0.0...
Connected to 0.
Escape character is '^]'.
telnet> quit

68. $ docker run -d --rm
-p 5432:5432
-v $(pwd)/data:/var/lib/postgresql/data
postgres
•
•

69. ...
****************************************************
WARNING: No password has been set for the database.
This will allow anyone with access to the
Postgres port to access your database. In
Docker's default configuration, this is
effectively any other container on the same
system.
Use "-e POSTGRES_PASSWORD=password" to set
it in "docker run".
****************************************************
...

70. $ docker run -d
-p 5432:5432
-e POSTGRES_PASSWORD=rootpassword
-v $(pwd)/data:/var/lib/postgresql/data
postgres
• https://hub.docker.com/_/
postgres

71. $ docker run -d
-p 5432:5432
-e POSTGRES_PASSWORD=rootpassword
-v $(pwd)/data:/var/lib/postgresql/data
postgres

72. •
$ docker run -d
-p 5432:5432
-e POSTGRES_PASSWORD=rootpassword
-v $(pwd)/data:/var/lib/postgresql/data
postgres

73. # ./docker-compose.yml
version: '3'
services:
db:
image: postgres
environment:
- POSTGRES_PASSWORD=rootpassword
volumes:
- ./data:/var/lib/postgres/data
ports:
- 5432:5432

74. • : docker-compose up -d
• : docker-compose ps
• : docker-compose logs
• : docker-compose down

75. • : docker-compose up -d
• -d
• : docker-compose ps
• : docker-compose logs -f
• -f
• : docker-compose down

76. •
• ./data

77. •

78. version: '3'
volumes:
postgres_data: {}
services:
db:
image: postgres
...
volumes:
- postgres_data:/var/lib/postgres/data

79. postgres
/var/lib/postgres/data
postgres_data

80. •
• docker volume ls
• docker volume ls | grep postgres
• docker-compose
• docker-compose down -v

81. version: '3'
...
services:
db:
image: postgres
environment:
- POSTGRES_PASSWORD=rootpassword
- POSTGRES_USER=django
- POSTGRES_PASSWORD=django_password
- POSTGRES_DB=djangodb
volumes:
...

82. •

83. db:
...
ports:
- 15432:5432
...
$ telnet 0 15432

85. Django
8000
HOST_IP
db.sqlite3

86. Django Postgres
5432
8000
HOST_IP

87. $ docker build -t docker-sample .
$ docker run -d --rm -p 8000:8000 docker-sample

89. # http://bit.ly/msl-django-database
# django/sample/settings.py
DATABASES =
'default': {
'ENGINE': 'django.db.backends.postgresql',
'NAME': os.environ.get('DJANGO_DB_NAME',
'djangodb'),
'USER': os.environ.get('DJANGO_DB_USERNAME',
'django'),
'PASSWORD': os.environ.get('DJANGO_DB_PASSWORD',
'django_password'),
'HOST': os.environ.get('DJANGO_DB_HOST', 'db'),
'PORT': os.environ.get('DJANGO_DB_PORT', '5432'),
}
}

90. # django/requirements.txt
...
psycopg2-binary

91. # http://bit.ly/msl-postgres-docker
$ docker run -d
--name db
-p 5432:5432
-e POSTGRES_DB=djangodb
-e POSTGRES_USER=django
-e POSTGRES_PASSWORD=djangopassword
-v $(pwd)/data:/var/lib/postgresql/data
postgres

92. $ docker run -d --rm
-p 8000:8000
--link db:db
docker-sample
$ docker run -d --rm
-p 8000:8000
--link ABCD1234EFGH:db
docker-sample

93. # Dockerfile
...
RUN apt update && apt install -y postgres-
client
RUN pip install ...

94. •

95. docker run -d --rm
-p 8000:8000
--link db:db
-v $(pwd)/django:/usr/src/app
docker-sample

96. •
• PYTHONUNBUFFERED

97. # Dockerfile
FROM python:3
ENV PYTHONUNBUFFERED 1
...

98. $ docker build -t docker-sample .
$ docker run -d --rm
-p 8000:8000
--link db:db
-v $(pwd)/django:/usr/src/app
docker-sample

99. $ docker run -d
--name db
-p 5432:5432
-e POSTGRES_DB=djangodb
-e POSTGRES_USER=django
-e POSTGRES_PASSWORD=djangopassword
-v $(pwd)/data:/var/lib/postgresql/data
postgres
$ docker run -d --rm
-p 8000:8000
--link db:db
-v $(pwd)/django:/usr/src/app
docker-sample

103. # docker-compose.yml
version: '3'
services:
db:
...
django:
image: docker-sample
links:
- db:db
ports:
- 8000:8000
volumes:
- ./django:/usr/src/app

104. Django Postgres
*
8000
HOST_IP
docker-compose
bridge network

105. •
•
•
•

106. # docker-compose.yml
...
django
# image: django-sample
build:
context: .
dockerfile: ./compose/django/
Dockerfile-dev
...

107. # ./compose/django/Dockerfile-dev
FROM python:3
ENV PYTHONUNBUFFERED 1
RUN apt update && apt install -y postgresql-client
WORKDIR /usr/src/app
COPY django ./
COPY django/requirements.txt ./
RUN pip install -r requirements.txt
RUN python manage.py collectstatic --noinput
CMD ["gunicorn", "sample.wsgi", "--bind=0:8000"]

108. •

109. http://bit.ly/msl-django-postgres

110. version: '3'
services:
django:
build:
context: .
dockerfile: ./compose/django/Dockerfile-dev
links:
- db:db
ports:
- 8000:8000
volumes:
- ./django:/usr/src/app
restart: always

111. ...
db:
image: postgres
environment:
- POSTGRES_PASSWORD=rootpassword
- POSTGRES_USER=django
- POSTGRES_PASSWORD=django_password
- POSTGRES_DB=djangodb
volumes:
- postgres_data:/var/lib/postgres/data
volumes:
postgres_data: {}

114. •
•
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•
•
•
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•
•

115. http://bit.ly/msl-practice-guestbook

116. version: '3'
services:
frontend:
image: raccoony/guestbook-frontend:latest
ports:
- "60081:8080"
environment:
- PORT=8080
- GUESTBOOK_API_ADDR=backend:5000
depends_on:
- backend
backend:
image: raccoony/guestbook-backend:latest
environment:
- PORT=5000
- GUESTBOOK_DB_ADDR=mongodb:27017
depends_on:
- mongodb

117. backend:
image: raccoony/guestbook-backend:latest
environment:
- PORT=5000
- GUESTBOOK_DB_ADDR=mongodb:27017
depends_on:
- mongodb
mongodb:
image: mongo:4
volumes:
- mongo_data:/data/db
volumes:
mongo_data:{}

118. • exec
• run
• build

119. docker-compose run django ./manage.py
migrate
docker-compose run django bash

120. docker-compose exec django ./manage.py
check
docker-compose exec django bash

121. docker-compose build django

122. # ~/.bashrc
alias dco='docker-compose'
alias dcb='docker-compose build'
alias dce='docker-compose exec'
alias dcps='docker-compose ps'
alias dcr='docker-compose run'
alias dcup='docker-compose up'
alias dcdn='docker-compose down'
alias dcl='docker-compose logs'
alias dclf='docker-compose logs -f'

123. raccoonyy@gmail.com
https://44bits.io
https://raccoonyy.github.io
raccoonyy
raccoonyy