Django Sample Microservice

This is an example microservice written in Django, intended to be used as part of 2hog's Docker trainings.

Spec

Implements a single endpoint (GET /) which:

1. Requires session authentication
2. Requests a greeting via a POST request from the greeting service
3. Requests an HTML fragment for the received greeting via a GET request from the content service
4. Returns an HTML document to the user, including the received HTML fragment

Configuration

The Django Sample Microservice accepts configuration via environment variables:

• POSTGRES_HOST: The hostname of the Postgres server (default: postgres)
• POSTGRES_USER: The Postgres user of the database (default: postgres)
• POSTGRES_PASSWORD: The password of the Postgres user(default: password)
• POSTGRES_PORT: The port to which the Postgres server listens (default: 5432)
• ALLOWED_HOSTS: The Host header values allowed to be used in this microservice (default: localhost)
• POSTGRES_DB: The Postgres database to use (default: postgres)
• SECRET_KEY: Secret key used by Django for cookie signing (default: thisshouldstaysecretforchristssake)
• GREETING_APP_URL: The host of the greeting service (default: http://greeting:4567/)
• GREETING_APP_USER: The user to use for Basic Authentication in the greeting service (default: paris)
• GREETING_APP_PASSWORD: The password to use for Basic Authentication in the greeting service (default: kasidiaris)
• CONTENT_APP_URL: The host of the content service (default: http://content:5000/)
• CONTENT_APP_USER: The user to use for Basic Authentication in the content service (default: antonis)
• CONTENT_APP_PASSWORD: The password to use for Basic Authentication in the content service (default: kalipetis)

Secrets

The Django Sample Microservice also accepts and prefers configuration as secret files for the following settings:

• /run/secrets/database_url: The full connection URL for the PostgreSQL database
• /run/secrets/greeting_app_url: The host of the greeting service
• /run/secrets/greeting_app_user: The user to use for Basic Authentication in the greeting service
• /run/secrets/greeting_app_password: The password to use for Basic Authentication in the greeting service
• /run/secrets/content_app_url: The host of the content service
• /run/secrets/content_app_user: The user to use for Basic Authentication in the content service
• /run/secrets/content_app_password: The password to use for Basic Authentication in the content service

Deployment

Docker Swarm

docker secret create micro-django-database-url -
docker secret create micro-django-secret-key -
docker secret create micro-django-greeting-app-url -
docker secret create micro-django-greeting-app-user -
docker secret create micro-django-greeting-app-password -
docker secret create micro-django-content-app-url -
docker secret create micro-django-content-app-user -
docker secret create micro-django-content-app-password -
docker stack deploy -c docker-compose.yml docker-training-samples-micro-django

Kubernetes

kubectl create secret generic docker-training-samples-micro-django-configmap \
--from-literal=allowed_hosts="${HOSTNAME}.akalipetis.com"
kubectl create secret generic docker-training-samples-micro-django-secret \
--from-literal=database_url=postgres://postgres:password@docker-training-samples-postgres:5432/postgres \
--from-literal=postgres_host=docker-training-samples-postgres \
--from-literal=postgres_user=postgres \
--from-literal=postgres_password=password \
--from-literal=postgres_port=5432 \
--from-literal=postgres_db=postgres \
--from-literal=secret_key=thisshouldstaysecretforchristssake \
--from-literal=greeting_app_url=http://docker-training-samples-sinatra:4567/ \
--from-literal=greeting_app_user=paris \
--from-literal=greeting_app_password=kasidiaris \
--from-literal=content_app_url=http://docker-training-samples-flask:5000/ \
--from-literal=content_app_user=antonis \
--from-literal=content_app_password=kalipetis
kubectl apply -f kube/

Development

To develop the Django Sample Microservice, follow these steps:

1. Install Docker (docs) and Docker Compose (docs)
2. Clone this repository:

   git clone https://github.com/2hog/docker-training-samples-micro-django
   

3. Launch the app with Docker Compose:

   docker-compose up
   

4. Open your repository with your editor and rock n' roll!

License

This software is MIT licensed.