how to deploy fast-api on ubuntu 22.04 for real project? (step-by-step tutorial)

Fast_API_deploy.md

Deploy a FastAPI app on Ubuntu 22.04 VPS

Deploying a FastAPI application on Ubuntu 22.04 for a real project involves several steps, including setting up the server, installing necessary software, configuring the application, and setting up a reverse proxy. Here's a step-by-step tutorial

Step 1: Update System

First, update your system packages:

sudo apt update

Step 2: Install Python and Pip

Install Python and Pip if they are not already installed:

sudo apt install python3 python3-pip

Step 3: Install and Configure a Virtual Environment

Create a virtual environment for your FastAPI project:

sudo apt install python3.10-venv
python3 -m venv fastapi-env
source fastapi-env/bin/activate

Step 4: Install FastAPI¹ and Uvicorn²

Install FastAPI and Uvicorn within your virtual environment:

pip install fastapi
pip install 'uvicorn[standard]'

Step 5: Create a Sample FastAPI Application

Create project folder and main.py file:

mkdir my_fastapi_project
cd my_fastapi_project
touch main.py

Create a sample FastAPI application. For example, edit a file named main.py:

vim main.py

from fastapi import FastAPI

app = FastAPI()

@app.get("/")
def read_root():
    return {"Hello": "World"}

Step 6: Test the Application Locally

Run the application locally to ensure it works:

uvicorn main:app --reload

You should be able to access the application at http://127.0.0.1:8000.

For test in any browser run the application with real IP on 80 port:

uvicorn main:app --host 85.159.231.14 --port 80 --workers 4

Step 7: Set Up Gunicorn³ to Serve the FastAPI Application

Install Gunicorn:

pip install gunicorn

Create file gunicorn_conf.py for settings Gunicorn:

vim gunicorn_conf.py

bind = "0.0.0.0:8000"
workers = 4

Run Gunicorn with Uvicorn worker:

gunicorn -k uvicorn.workers.UvicornWorker -c gunicorn_conf.py main:app

Step 8: Install and Configure Nginx⁴

Install Nginx to act as a reverse proxy:

sudo apt install nginx

Create a new Nginx configuration file for your FastAPI application:

sudo nano /etc/nginx/sites-available/fastapi

Add the following content to the file, replacing your_domain with your actual domain or IP address:

server {
    listen 80;
    server_name your_domain;

    location / {
        proxy_pass http://127.0.0.1:8000;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Enable the configuration by creating a symbolic link:

sudo ln -s /etc/nginx/sites-available/fastapi /etc/nginx/sites-enabled/
sudo nginx -t
sudo systemctl restart nginx

Step 9: Set systemd for autostart

Create a Gunicorn systemd service file:

sudo vim /etc/systemd/system/fastapi.service

Add the following content:

[Unit]
Description=FastAPI service
After=network.target

[Service]
User=root
Group=root
WorkingDirectory=/root/my_fastapi_project
ExecStart=/root/fastapi-env/bin/gunicorn -k uvicorn.workers.UvicornWorker -c /root/my_fastapi_project/gunicorn_conf.py main:app

[Install]
WantedBy=multi-user.target

Replace /path/to/your/project with the actual path to your FastAPI project.

Reload systemd to apply the new service, start it, and enable it to run on boot:

sudo systemctl daemon-reload
sudo systemctl start fastapi
sudo systemctl enable fastapi

Step 10: Open Firewall Ports

If you have a firewall enabled, you need to allow traffic on port 80 (HTTP):

sudo ufw allow 'Nginx Full'
sudo ufw enable

Step 11: Check Your Deployment

Your FastAPI application should now be accessible at your domain or IP address. Open a web browser and go to http://your_domain.

journalctl -u fastapi.service
systemctl status fastapi
vim /var/log/nginx/error.log

Optional: Setting Up HTTPS with Let's Encrypt

For a secure connection, you can set up HTTPS using Let's Encrypt:

sudo apt install certbot python3-certbot-nginx -y
sudo certbot --nginx -d your_domain

Follow the prompts to complete the installation and obtain your SSL certificate.

Conclusion

You've successfully deployed a FastAPI application on Ubuntu 22.04. This setup includes running FastAPI with Gunicorn, serving it behind Nginx as a reverse proxy, and optionally securing it with HTTPS using Let's Encrypt. Make sure to replace placeholder values with your actual domain, paths, and project specifics.

Footnotes

1. https://fastapi.tiangolo.com/ ↩

2. https://www.uvicorn.org/ ↩

3. https://gunicorn.org/ ↩

4. https://nginx.org/ ↩