0) Tree overview

tree -L 2 -I __pycache__ -I venv/

.
├── alembic
│   ├── env.py
│   ├── migration
│   ├── README
│   ├── script.py.mako
│   └── versions
│       ├── 210bb53de308_add_is_active.py
│       ├── 83ad6d6f77c4_create_user_table.py
│       ├── 87acc7a1e86f_create_employee_week_calendar_table.py
│       ├── 93e3cb2b3fcf_add_press_details_data.py
│       └── ea6b75090bef_add_employee_press_employee_role.py
├── alembic.ini
├── app
│   ├── config.py
│   ├── database.py
│   ├── __init__.py
│   ├── main.py
│   ├── models.py
│   ├── oauth2.py
│   ├── routers
│   │   ├── auth.py
│   │   └── employee.py
│   ├── schemas.py
│   ├── tests
│   │   ├── conftest.py
│   │   ├── create_employee_test.py
│   │   └── __init__.py
│   └── utils.py
├── press.db
├── press.service
├── press-test.db
├── README.md
└── requirements.txt

1) Getting started

git clone https://github.com/vinthara/press-fastapi

cd press-fastapi

Create venv/ :

python3 -m venv venv

Activate the virutal environment for dependencies venv :

source venv/bin/activate

Install all the dependencies :

pip3 install -r requirements.txt 

You need to add .env in press-fastapi/

SQLALCHEMY_DATABASE_URL="URI"
SQLALCHEMY_DATABASE_TEST_URL="URI_TEST"
SECRET_KEY="run this command openssl rand -hex 32"
ALGORITHM="An algorithm"

You can now start the app :

uvicorn app.main:app --reload

2) How to use alembic

Alembic is useful for doing schema migration, when you need to add columns, alter columns, you can even do small data migration, like adding some rows to a table.

There is an alembic.ini file :

Which contains the following :

[test]
script_location = alembic
prepend_sys_path = .
version_path_separator = os
env = test

[prod]
script_location = alembic
prepend_sys_path = .
version_path_separator = os
env = prod

Inside alembic/env.py :

There is the following added :

sqlalchemy_url = settings.sqlalchemy_database_test_url

if config.get_main_option("env") == "prod":
    sqlalchemy_url = settings.sqlalchemy_database_url

config.set_main_option("sqlalchemy.url", sqlalchemy_url)

This allow us to run alembic schema migration on the wanted database :

alembic -n test downgrade -1

alembic -n prod upgrade +1