Provides a Django management command to check whether the primary database is ready to accept connections.
Run this command in a Kubernetes or OpenShift Init Container to make your Django application wait until the database is available (e.g. to run database migrations).
wait_for_database
is a single command for all database engines
Django supports. It automatically checks the database you have configured
in your Django project settings. No need to code a specific wait command
for Postgres, MariaDB, Oracle, etc., no need to pull a database engine
specific container just for running the database readiness check.
The easiest way to install django-probes is with pip
$ pip install django-probes
- Add django-probes to your Django application:
INSTALLED_APPS = [
...
'django_probes',
]
2. Add an Init Container to your Kubernetes/OpenShift deployment
configuration, which calls the wait_for_database
management command:
- kind: Deployment
apiVersion: apps/v1
spec:
template:
spec:
initContainers:
- name: wait-for-database
image: my-django-app:latest
envFrom:
- secretRef:
name: django
command: ['python', 'manage.py', 'wait_for_database']
Alternatively, you can integrate the wait_for_database
command in your
own management command, and do things like database migration, load initial
data, etc. with roughly the same Kubernetes setup as above.
from django.core.management import call_command
# ...
call_command('wait_for_database')
The management command comes with sane defaults, which you can override if needed:
--timeout, -t: | how long to wait for the database before timing out (seconds), default: 180 |
---|---|
--stable, -s: | how long to observe whether connection is stable (seconds), default: 5 |
--wait-when-down, -d: | delay between checks when database is down (seconds), default: 2 |
--wait-when-alive, -a: | delay between checks when database is up (seconds), default: 1 |
--database: | which database of settings.DATABASES to wait for, default: default |