Flask, Gunicorn, Docker and Traefik

Working this out took 3 days to get the result below; the biggest issue faced is that there are SO MANY ways each solution can be configured and so MANY MANY ways these configurations can break the other.

Result

URL localhost:8080

This gives THREE routes on same server that will show the flask app.

URL: http://web2.localhost/web2/. Show a route to web2

URL: http://web2.localhost/web2/, Show web2 route within a subdomain

URL: http://localhost/. Default route

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So here is how I got it working…

0. Install Docker Desktop, take the default settings; nothing special here

1. Create a directory for the Docker Flask — Gunicorn app with the following files.

2. Create a directory for the Traefik container which will be a reverse proxy for the web app

3. Create a network in Docker for BOTH containers to connect to (THIS IS VERY IMPORTANT!)

docker network create backendweb

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1…setup files

2…setup files

To run the project…

cd {directory of the files in dockerapp}

docker image build -t flask_docker .

Now you have the flask app, wrapped in gunicorn and in a docker container.

Run the container from the command line

docker-compose up

cd {directory of the files in reverseproxy}

docker-compose up

Thats it.

It should work now :-)