Project structure: Tutorial series

python main.py

• Login: /auth/login
• Logout: /auth/logout
• Profile: /auth/profile
• Register: /auth/register
• Upload: /file/upload

The python packages needed to run the webapp can be installed with:

pip install -r requirements.txt

flask-migrate is an extension based on Alembic, a migrations tool for SQLAlchemy. The following instructions use it to first add a migrations folder at the root of the project, then to create a new migration and finally apply it:

0. Define environment variable: export FLASK_APP=main.py
1. flask db init
2. flask db migrate -m "message"
3. flask db upgrade

An instance folder needs to be created at the root of the project to contain database access credentials. For that, instance/config.py will have to contain:

import os


# needed by csrf field in wtforms & user passwords)
SECRET_KEY = os.urandom(32)

# database access
SQLALCHEMY_DATABASE_URI = "postgresql://<user>:<password>@<host>/<database>"

If the password of the user used to login to pgadmin4 was forgotten, it can be reset with:

ALTER USER user_name WITH PASSWORD 'new_password';

The files uploaded through this web application should also be placed inside the instance folder (e.g. inside a photos subdirectory).

The docker image was deployed on the docker-hub. The following commands were used to build and tag the image, and deploy it to the hub:

docker build -t <hub-user>/<repo-name> .
docker login
docker push <hub-user>/<repo-name>

To download the image on another machine:

docker run <hub-user>/<repo-name>