docker-compose does not start postgres

Question

I m creating a docker-compose config for an django app, the Dockerfile builds successfully but when I compose them up, django return an issue -- cannot connect to postgres.

I run docker-compose run web bash, found redis and posgres both cannot be connected.

My docker-compose.yml file

web:
 build: .
  ports:
    - "8000:8000"
environment:
  - 'DATABASE_HOST=db'
  - 'DATABASE_NAME=mydb'
  - 'DATABASE_USER=root'
  - 'DATABASE_PASSWORD=root'
links:
  - db
db:
  image: postgres:9.1

when running sudo docker-compose up i got the following error.

web_1 |   File "/usr/local/lib/python2.7/site packages/django/db/backends/postgresql/base.py", line 175, in  get_new_connection

web_1 |     connection = Database.connect(**conn_params)
web_1 |   File "/usr/local/lib/python2.7/site-packages/psycopg2/__init__.py", line 164, in connect
web_1 |     conn = _connect(dsn, connection_factory=connection_factory, async=async)
web_1 | django.db.utils.OperationalError: could not connect to server: Connection refused
web_1 |     Is the server running on host "localhost" (::1) and accepting
web_1 |     TCP/IP connections on port 5432?
web_1 | could not connect to server: Connection refused
web_1 |     Is the server running on host "localhost" (127.0.0.1) and accepting
web_1 |     TCP/IP connections on port 5432?

Answer 1

I also built a clustering with docker-compose , it probably will help you and answer your problem (here is the repo ). You can see the docker-compose.yml file, and the django settings file (I marked the lines you need).

You can also clone this repo and get django , angular2 , postgresql , and nginx containers, all link together already.

Answer 2

You are linking your web container with the postgres container but you are not defining database name, password and user.

  web:
   build: .
   ports:
    - "8000:8000"
   links:
    - db
  db:
    restart: always
    image: postgres:9.1
    ports:
      - "5432:5432"
    volumes:
      - pgvolume:/var/lib/postgresql/data
    environment:
      - POSTGRES_PASSWORD=root
      - POSTGRES_DB= aiotadb
      - POSTGRES_USER=root
   data:
    restart: always
    image: postgres:9.1
    volumes:
      - /var/lib/postgresql
    command: tail -f /dev/null

Also, if you already define your database options in your settings file, you don't need to declare it as env variables in web container.

Answer 3

version: '3'
services:
  basicproject:
    build: .
    container_name: basicproject-container
    depends_on:
      - postgres
    ports:
      - "8000:8000"

  postgres:
    image: postgres:9.4
    ports:
    - "5432"
    environment:
      - POSTGRES_USER=test
      - POSTGRES_PASSWORD=testing
      - POSTGRES_DB=test_db

Answer 4

Add dependency in your 'web' service like below:

depends_on:
  - db