Deploy Python/Django app as Docker container on fly.io's Public Cloud

Author: aashutosh

Updated: 9 Mar 2023 12:41 p.m.

Tags: #Python #Django #Docker #Cloud #fly.io

Summary : Deploy a full stack Python Django application as a Docker container image on fly.io Platform as a Service (PaaS) Public Cloud . Connect a Postgres Database running on Fly.io to Django app.

Fly Cloud transforms docker container images into and run as Firecracker (open source virtualization technology) micro-VM on bare metal servers across Data centers.

 

Step 1:  Install flyctl

 

Step 2:  Change directory to Django project

 

Step 3:  Copy Python Package dependency list to requirements.txt

 

Step 4:    Configure Django app with flyctl launch

fly launch

 

fly launch scan & detect source code automatically as a Djnago app and create two files with settings configured for deploying Djangi application: 

1. fly.toml  : contains configuration details like below to run as Django app on container/Micro VM, modify it suit your needs, but it comes with default setting required to deploy Django app. 

• fly app name,
• port details and other
• release management command
• app = "aashutosh"
kill_signal = "SIGINT"
kill_timeout = 5
processes = []
[deploy]
  release_command = "python manage.py migrate"
[env]
  PORT = "8000"
[experimental]
  auto_rollback = true
[[services]]
  http_checks = []
  internal_port = 8000
  processes = ["app"]
  protocol = "tcp"
  script_checks = []
  [services.concurrency]
    hard_limit = 25
    soft_limit = 20
    type = "connections"
  [[services.ports]]
    force_https = true
    handlers = ["http"]
    port = 80
  [[services.ports]]
    handlers = ["tls", "http"]
    port = 443
  [[services.tcp_checks]]
    grace_period = "1s"
    interval = "15s"
    restart_limit = 0
    timeout = "2s"
[[statics]]
  guest_path = "/app/public"
  url_prefix = "/static/"

2. Dockerfile

• Steps to deploy Django app as Container Image
• Replace Dockerfile CMD command with actual Django project wsgi file
• # replace demo.wsgi with <project_name>.wsgi
CMD ["gunicorn", "--bind", ":8000", "--workers", "2", "core.wsgi"]
• 
  Dockerfile
• ARG PYTHON_VERSION=3.10-slim-buster
FROM python:${PYTHON_VERSION}
ENV PYTHONDONTWRITEBYTECODE 1
ENV PYTHONUNBUFFERED 1

RUN mkdir -p /code
WORKDIR /code
COPY requirements.txt /tmp/requirements.txt

RUN apt-get update

# Install psycopg2 dependency - libpq-dev, gcc
RUN apt-get -y install libpq-dev gcc
RUN set -ex && \
    pip install --upgrade pip && \
    pip install -r /tmp/requirements.txt && \
    rm -rf /root/.cache/

# Copy Local Source code to image:/code
COPY . /code/

# Copy certificate files
# RUN mkdir ~/.postgresql/root.crt
# COPY cockroach_db/root.crt ~/.postgresql/root.crt

RUN python manage.py collectstatic --noinput
EXPOSE 8000

# replace demo.wsgi with <project_name>.wsgi
CMD ["gunicorn", "--bind", ":8000", "--workers", "2", "core.wsgi"

 

 

Step 5: Deploy App

fly deploy will build the image from Dockerfile and push it on Fly.io

Deploy Django app using fly deploy, this command will build the image using information/steps from Dockerfile, and will push the image to Fly.io and run the application using settings from fly.toml

Once deployment is successful, Django app can be accessed online

 

Step 6: Open App

Browse to https://your-app-name.fly.dev/  (https://aashutosh.fly.dev/)
use fly open command to launch browser to https://your-app-name.fly.dev/ 

 

Step 7: Attach a Postgres Database to Django application on Fly.io

 

Step 8: ssh into Fly app instance console