Basic API Setup with FastAPI

Introduction

This article in the series will cover setting up a basic FastAPI project. The best tutorial for learning FastAPI is on their website. However, for the sake of continuity, I'll detail some steps here:

• Setting up a virtual environment
• Downloading necessary modules
• Creating project files
• Inserting starter code

Virtual Environment

First, create a new directory. Or, you can navigate (in a terminal or command shell) to the directory where you wish to create the project.

I made a directory called fastapi_tutorial.

Next, if you don't have it downloaded already, download virtualenv.

$ pip3 install virtualenv

This should install the package into your global Python interpreter or your current activated environment.

Now, we can create a new virtual environment for the project.

In the terminal run the command:

$ virtualenv venv

After the command is done, a new virtual environment folder is added to our project folder. The name of our new environment is venv.

Finally, we need to activate the environment with:

$ source venv/bin/activate

Install Packages

Next, we need to install the packages necessary to run FastAPI locally.

$ pip3 install fastapi uvicorn

The uvicorn package is for running the local server. Additionally, installing fastapi installed:

• pydantic
• starlette
• typing-extensions

Create the Server File

Inside the root of the project, create the file main.py. Paste the below code into the file:

from fastapi import FastAPI

app = FastAPI()


@app.get("/")
async def root():
    return {"message": "Hello World"}

In this file, we create our API and store it in the app variable.

The "/" route is the index of our API. We add this route as the only route available. If you visit this route, you'll receive the return value, {"message": "Hello World"}.

Start the Server

With the virtual environment active, we can start the development server to run locally.

In the terminal, in the root directory, run the command:

uvicorn main:app --reload

You'll see some output and the line:

Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)

Open up a browser and enter http://localhost:8000 for the URL.

You should see our return value, {"message":"Hello World"}, and that means that we are successful!

In the next article, we'll explore FastAPI more and build out the information for our routes. Thanks for reading!