README.md

Backend

Requirements:

• Docker Or
• Python (v3.9) & Sqlite

The backend is split into three main parts. It consists of FastAPI, SqlAlchemy and Postgres. FastAPI is a framework for creating APIs in Python. SqlAlchemy is an ORM (Object Relational Mapper) that makes it easy to work with databases in Python. Postgres is the database used in production. In development, sqlite is used.

Setup & running

Development

Environment:

.env is not commited to this repo because of security, so this file has to be created.

Both frontend and backend folders includes a .env.template file. This file contains the variables that has to be set in the new .env file.

In the backend folder, create.envfile containing the following:

• production = false (This is used to determine if the database should be sqlite or postgres)
• SECRET_KEY = random_string (This is used for hashing)

Feide instance (this can be created here):

• client_id is set
• client_secret is set
• REDIRECT_URI is set
• BASE_URL is set

OpenAI authentication (this can be created here):

• OPENAI_KEY is set

Note: There are some optional variables in the .env.template file. These are not necessary for the application to run, but can be used for testing and development.

Running Backend :

Note: For linting the backend, the VScode extention Black Formatter is used. This is also visible in the .gitlab-ci.yml-file where we have a job for checking the linting of the backend.

Alternative 1 (docker):

This is the recommended way to run the backend. This will start the backend in a Docker container. To do this, run the following command:

make dev

If you are using Windows, you can run the following commands (every command in the Makefile) manually in the terminal:

docker-compose up --no-deps backend

Alternative 2 (manual setup):

cd backend

# Creates virtual environment
python -m venv venv # only do once

# Activates virtual environment
source ./venv/bin/activate #Troubleshooting for windows below

# Installing python packages
pip install -r requirements.txt

# Apply migration scripts
alembic upgrade head

# Run the backend
uvicorn main:app --reload

# Running at 127.0.0.1:8000

Migrations (optinal but not necessary):

Migration: alembic is used for databse migration (kind of git for databases). You can read more about alembic here, or take a look at this tutorial video.

When ANY changes is made to the database model file, then a migration has to happen. This is done by the following commands:

# Create migration
alembic revision --autogenerate -m "Revision message, something relevant here"

# Apply latest migration
alembic upgrade head

Run tests:

To run the tests, run the following command:

make test-backend

Or if you are using Windows, you can run the following described in the Makefile here

Test result:

Troubleshooting (for manual setup):

The command

source ./venv/bin/activate

Is intended for Linux and does not always work on windows. Therefore, windows users using VS code, could install the extension Powershell (Picture below), to run the activate script in the venv-folder. Then manually run the script by clicking the script and clicking run.

1. First install the Powershell extension

2. Then go into backend/venv/Scripts/Activate.ps1 and run the script.

3. Click this file and run it. If you see a green (venv) in the terminal, then the virtual environment is activates. You can now run the rest of the commands above.

4. You can now run the rest of the commands to setup and run backend

# Installing python packages
pip install -r requirements.txt

# Apply migration scripts
alembic upgrade head

# Run the backend
uvicorn main:app --reload

# Running at 127.0.0.1:8000