simple-flask-on-docker

This is a simple python-based flask application exposed using a nginx server via a gunicorn gateway. It also has a dockerized postgres database which can be used as the database for a more advanced python application.

Prerequisites

Git

Use the following URL and follow the guidelines according to your Operating System to install git. https://github.com/git-guides/install-git

Docker

Use the following URL and follow the guidelines according to your Operating System to install docker engine or docker desktop. https://docs.docker.com/engine/install/

Docker-compose

If you have already installed docker desktop, skip this step. If you installed docker engine use the following URL to install docker-compose. https://docs.docker.com/compose/install/linux/#install-using-the-repository

User Privileges

The user should have privileges to execute docker commands. If the user is root, skip the following steps.

Check the groups assigned for the user using the following command, which will return the groups of user foo. Replace foo with respective username.

groups foo

If the user is not in docker group, then execute the following command with a user that has sudo or root privileges. It will assign user foo to docker group. Replace foo with respective username.

sudo usermod -aG foo docker

Setup

Run the following command to clone the Github repository to the local machine.

https://github.com/Sahan-Rathnayake/simple-flask-on-docker.git

Navigate into the root directory

cd simple-flask-on-docker/

Run the following command to build the docker images and start the containers.

docker-compose up -d --build

Run the following command to inspect the started containers.

docker ps

Open browser and navigate to http://127.0.0.1 and it should direct into a web page displaying Hello World

Troubleshooting

If the web page cannot be viewed with error ERR_CONNECTION_REFUSED, run the following command to view the containers.

docker ps -a

If either proxy or app container is not ready or restarting, run the following command to inspect the logs.

# outputs logs of all services
docker-compose logs

# outputs logs of app
docker-compose logs app

# outputs logs of proxy
docker-compose logs proxy