Flask Sample Microservice

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

Spec

It implements a single endpoint (GET /), which:

1. Requires basic authentication
2. Returns an HTML page fragment, based on the given greeting URL parameter

Example

paris@docker-training-samples-micro-flask:/mnt/project$ curl -u antonis:kalipetis http://localhost:5000/?greeting=Konichiwa
<h1>Konichiwa, trainee!</h1>
<p>This is a simple Flask microservice that we wrote for you.</p>

Configuration

The Flask Sample Microservice accepts configuration via environment variables:

• AUTH_USER: The username to use for Basic Authentication (default: antonis)
• AUTH_PASSWORD: The password to use for Basic Authentication (default: kalipetis)
• DEBUG: Enable debugging mode and print environment information (default: 0 in production, 1 in development)
• ENVIRONMENT: Environment in which the application runs (default: production in production, development in development)

Secrets

The Flask Sample Microservice also accepts and prefers configuration for AUTH_USER and AUTH_PASSWORD as secret files:

• /run/secrets/auth_user: The username to use for Basic Authentication
• /run/secrets/auth_password: The password to use for Basic Authentication

Deployment

Docker

docker run -d \
-e AUTH_USER=antonis -e AUTH_PASSWORD=kalipetis \
-e DEBUG=true -e ENVIRONMENT=staging \
-p 5000 \
2hog/docker-training-samples-micro-flask

Docker Swarm

docker secret create micro-flask-auth-user -
docker secret create micro-flask-auth-password -
docker stack deploy -c docker-compose.yml docker-training-samples-micro-flask

Kubernetes

kubectl create secret generic docker-training-samples-micro-flask-secret \
--from-literal=auth_user=antonis \
--from-literal=auth_password=kalipetis
kubectl apply -f kube/

Development

To develop the Flask 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-flask
   

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.