Connection refused with psql django and docker (cookiecutter-django) - django

Question

My django app is failing to connect to the psql container with the standard connection refused error. I used django-cookiecutter which supplies the psql username and password automatically via environment variables and then this I gather is passed back into django with via a .env file that hosts a DATABASE_URL string.
Error
django.db.utils.OperationalError: could not connect to server: Connection refused
Is the server running on host "127.0.0.1" and accepting
TCP/IP connections on port 5432?
When I set a breakpoint in django settings I can see that the DATABASE_URL seems to be converted appropriately into the standard db dict:
{'NAME': 'hustlestat', 'USER': 'HjhPLEwuVjUIIKEHebPqNG<redacted>', 'PASSWORD': 'I43443fR42wRkUaaQ8mkd<redacted>', 'HOST': 'postgres', 'PORT': 5432, 'ENGINE': 'django.db.backends.postgresql'}
When I exec into the psql container with psql hustlestat -U HjhPLEwuVjUIIKEHebPqN<redcated> I can connect to the db using that username. I'm not 100% on the password as it isn't asking me for one when I try to connect.
Here is the docker compose which is generated automatically by cookie cutter:
version: '3'
volumes:
local_postgres_data: {}
local_postgres_data_backups: {}
services:
django: &django
build:
context: .
dockerfile: ./compose/local/django/Dockerfile
image: hustlestat_local_django
container_name: django
depends_on:
- postgres
- mailhog
volumes:
- .:/app:z
env_file:
- ./.envs/.local/.django
- ./.envs/.local/.postgres
ports:
- "8000:8000"
command: /start
postgres:
build:
context: .
dockerfile: ./compose/production/postgres/Dockerfile
image: hustlestat_production_postgres
container_name: postgres
volumes:
- local_postgres_data:/var/lib/postgresql/data:Z
- local_postgres_data_backups:/backups:z
env_file:
- ./.envs/.local/.postgres
docs:
image: hustlestat_local_docs
container_name: docs
build:
context: .
dockerfile: ./compose/local/docs/Dockerfile
env_file:
- ./.envs/.local/.django
volumes:
- ./docs:/docs:z
- ./config:/app/config:z
- ./hustlestat:/app/hustlestat:z
ports:
- "7000:7000"
command: /start-docs
mailhog:
image: mailhog/mailhog:v1.0.0
container_name: mailhog
ports:
- "8025:8025"
redis:
image: redis:5.0
container_name: redis
celeryworker:
<<: *django
image: hustlestat_local_celeryworker
container_name: celeryworker
depends_on:
- redis
- postgres
- mailhog
ports: []
command: /start-celeryworker
celerybeat:
<<: *django
image: hustlestat_local_celerybeat
container_name: celerybeat
depends_on:
- redis
- postgres
- mailhog
ports: []
command: /start-celerybeat
flower:
<<: *django
image: hustlestat_local_flower
container_name: flower
ports:
- "5555:5555"
command: /start-flower
node:
build:
context: .
dockerfile: ./compose/local/node/Dockerfile
image: hustlestat_local_node
container_name: node
depends_on:
- django
volumes:
- .:/app:z
# http://jdlm.info/articles/2016/03/06/lessons-building-node-app-docker.html
- /app/node_modules
command: npm run dev
ports:
- "3000:3000"
# Expose browsersync UI: https://www.browsersync.io/docs/options/#option-ui
- "3001:3001"
The only oddity I have noticed is that despite django being named in the docker compose, when I view the running containers it has a random name such as:
hustlestat_django_run_37888ff2c9ca
Not sure if that is relevant.
Thanks for any help!

Answer 1

Okay have figured this out. I set a DATABASE_URL environment variable because I was originally getting an error saying it was unset. After googling I came across a cookie cutter doc that said to set it but didn't read it well enough to realise that the instruction was intended for non-docker setups. Mine is docker.
The reason I was getting that error is because I was exec'ing into the container and running management commands like this:
docker exec -it django bash then python manage.py migrate
The way this project is setup and environment variables are setup, you can't do that, you have to use this method from outside the exec:
docker-compose -f local.yml run --rm django python manage.py migrate
I thought the two methods were interchangeable but they are not. Everything works now.