FastAPI SQLAlchemy Relationships Setup

Setup

In this lesson, we’ll start by working with a pre-existing application that utilizes a PostgreSQL database instance, SQLAlchemy models and a database seeded with initial data.

If you have a complete, working application from the Python FastAPI SQLAlchemy Models Lesson, you may choose to use that codebase as starter code instead of the repo provided below.

1. Clone the starter code

We’ve provided a starter repository with the base application code. Clone the repository to your local machine and rename the folder for this lesson:

git clone https://git.generalassemb.ly/modular-curriculum-all-courses/python-fastapi-sqlalchemy-models-solution python-fastapi-sqlalchemy-relationships
cd python-fastapi-sqlalchemy-relationships

2. Install dependencies:

This project uses pipenv for managing dependencies. To install everything the project needs, run:

 pipenv install

3. Activate the virtual environment:

 pipenv shell

4. Set up the database

1. Set up your PostgreSQL database:

   • Ensure PostgreSQL is installed and running on your machine.
   • Create a database named teas_db if it does not already exist:

createdb teas_db

5. Connect to database

Open the application in Visual Studio Code:

code .

The database connection string is defined in the config/environment.py file:

db_URI = "postgresql://<username>@localhost:5432/teas_db"

• Ensure your PostgreSQL instance is configured to allow connections with the provided credentials.
• Modify your database connection string to use your username as the <username>.

6. Seed the database

Seed the database with initial data:

• Run the seed.py file to reset the database by dropping existing tables and repopulating it with starter data:

pipenv run python seed.py

You should see output indicating the database was successfully seeded. If there are any errors, check the db_URI in the config/environment.py file.