HelloDjangoPostgres!

This is an example project demonstrating how to deploy a Django application with Postgres on Fly.io.

Local Development

The environment variables are stored in the .env file.

Duplicate .env.dist file and rename it to .env. Update the environment variables:

SECRET_KEY=<your-generated-django-secure-super-secret-key>
DEBUG=True
DATABASE_URL=postgres://<user>:<password>@<host>:<port>/<db>

The default DATABASE_URL is postgres://postgres:postgres@localhost:5432/hello_django (check hello_django/settings.py).

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Getting started

flyctl is the command-line utility provided by Fly.io.

If you still don't have installed it, you can follow the instructions here to install it, sign up and log in to Fly.io.

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Create and configure a new app (fly launch)

This simple app already contains all the basic configuration for deploying to Fly.io.

• Dockerfile contain commands to build the image.
• .dockerignore list of files or directories Docker will ignore during the build process.
• fly.toml configuration for deployment on Fly.io.

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Dockerfile

SECRET_KEY is required when running collectstatic. A default SECRET_KEY can be generated by using the get_random_secret_key function provided by Django:

# settings.py
from django.core.management.utils import get_random_secret_key
...
# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = env.str('SECRET_KEY', default=get_random_secret_key())

An alternative is to set a random key on Dockerfile for building purposes:

# Dockerfile
ENV SECRET_KEY "non-secret-key-for-building-purposes"  # <-- Set SECRET_KEY for building purposes
RUN python manage.py collectstatic --noinput

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When running fly launch, copy the existing configuration to your own app:

❯ fly launch
An existing fly.toml file was found for app hello-django-postgres
? Would you like to copy its configuration to the new app? Yes

Secrets

During the fly launch, the necessary secrets will be set:

• SECRET_KEY
• DATABASE_URL

Django SECRET_KEY

❯ fly launch
Creating app in /Projects/flyio/hello-django-postgres
Scanning source code
Detected a Django app
? Choose an app name (leave blank to generate one): hello-django-postgres
...
Hostname: hello-django-postgres.fly.dev
Set secrets on hello-django-postgres: SECRET_KEY  # <-- SECRET_KEY is set automatically

Postgres DATABASE_URL

Set up a Postgres database during the fly launch step:

❯ fly launch
Creating app in /Projects/flyio/hello-django-postgres
Scanning source code
Detected a Django app
? Choose an app name (leave blank to generate one): hello-django-postgres
...
? Would you like to set up a Postgresql database now? Yes  # <-- You will be asked HERE
? Select configuration: Development - Single node, 1x shared CPU, 256MB RAM, 1GB disk
Creating postgres cluster in organization fly-io
Creating app...
Setting secrets on app hello-django-postgres-db...
Provisioning 1 of 1 machines with image flyio/postgres:14.6
Waiting for machine to start...
....
Postgres cluster hello-django-postgres-db is now attached to hello-django-postgres
The following secret was added to hello-django-postgres:
  DATABASE_URL=postgres://hello_django_postgres:****@****:5432/hello_django_postgres?sslmode=disable
Postgres cluster hello-django-postgres-db is now attached to hello-django-postgres  # <-- postgres cluster attached to the app

Important: During this step, save your credentials in a secure place - you won't be able to see them again!

Your postgres cluster will be automatically attached to your app.

ALLOWED_HOSTS and CSRF_TRUSTED_ORIGINS

Before we can deploy it, make sure to update ALLOWED_HOSTS and CSRF_TRUSTED_ORIGINS in hello_django/settings.py with the chosen/generated app name on Fly.io.

ALLOWED_HOSTS = ['127.0.0.1', 'localhost', '<your-app-name>.fly.dev']
CSRF_TRUSTED_ORIGINS = ['https://<your-app-name>.fly.dev']

Your Django app is now ready to be deployed!

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Deploy (fly deploy)

Once all the previous steps are done, you can deploy your app:

❯ fly deploy
==> Verifying app config
--> Verified app config
==> Building image
...
 1 desired, 1 placed, 1 healthy, 0 unhealthy [health checks: 1 total, 1 passing]
--> v0 deployed successfully

Your app is now up and running!

❯ fly open