Tutorial: Setting Up a FastAPI Server with Nginx Reverse Proxy and HTTPS

In this tutorial, I will guide you through setting up a FastAPI server on a remote machine, configuring Nginx as a reverse proxy, and enabling HTTPS using Certbot.

Step 1: Setting Up a Non-sudo User on the Remote Machine

1. Create a Non-sudo User:

   sudo adduser karthik
   

2. Switch to the New User:

   su karthik
   

3. Create SSH Directory and Authorized Keys:

   cd ~/
   mkdir .ssh
   touch .ssh/authorized_keys
   

   Append your local machine's SSH public key to ~/.ssh/authorized_keys on the remote machine.

Step 2: Installing Nginx

1. Install Nginx:

   sudo apt-get update
   sudo apt-get install nginx
   

2. Verify Nginx Installation: Open a web browser and enter your remote machine's IP address. You should see the Nginx welcome page.

Step 3: Configuring Nginx as a Reverse Proxy

1. Edit Nginx Configuration:

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

   Add the following configuration (use a simple webserver for testing this):

   server {
       listen 80;
       server_name your_domain;
   
       location / {
           proxy_pass http://127.0.0.1:8000; # FastAPI server address
           proxy_set_header Host $host;
           proxy_set_header X-Real-IP $remote_addr;
           proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
       }
   }
   

2. Enable the Site:

   sudo ln -s /etc/nginx/sites-available/fastapi /etc/nginx/sites-enabled/
   

3. Test Nginx Configuration:

   sudo nginx -t
   

4. Restart Nginx:

   sudo systemctl restart nginx
   

Step 4: Enabling HTTPS with Certbot

Note : You need to create a A type DNS Record from your domain registar pointing to your static public ip address before this step, otherwise certbot will fail to generate certificates.

1. Install Certbot for Nginx:

   sudo apt-get install python3-certbot-nginx
   

2. Obtain SSL Certificate:

   sudo certbot certonly --nginx -d your_domain_or_subdomain
   

3. Update Nginx Configuration for HTTPS: Update /etc/nginx/sites-available/fastapi with HTTPS settings:

   server 
    {
        listen 80;
        listen [::]:80;
        server_name your_domain;
   
        # Redirect all HTTP traffic to HTTPS
        if ($host = $server_name) {
            return 301 https://$host$request_uri;
        }
   
        return 404;
    }
   
    server 
    {
        listen 443 ssl;
        listen [::]:443 ssl;
        server_name your_domain;
   
        ssl_certificate /etc/letsencrypt/live/your_domain/fullchain.pem;
        ssl_certificate_key /etc/letsencrypt/live/your_domain/privkey.pem;
        include /etc/letsencrypt/options-ssl-nginx.conf;
        ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;
   
        keepalive_timeout 5;
        client_max_body_size 1G;
   
        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;
        }
    }
   

4. Test Nginx Configuration and Restart:

   sudo nginx -t
   sudo systemctl restart nginx
   

Step 5: Deploying FastAPI Server

1. Install Micromamba and Create Virtual Environment:

   "${SHELL}" <(curl -L micro.mamba.pm/install.sh)
   micromamba create -n myenv python=3.8
   micromamba activate myenv
   

2. Install Dependencies and Start FastAPI Server:

   pip install fastapi uvicorn gunicorn
   mkdir ~/Projects/myproject
   cd ~/Projects/myproject
   touch main.py
   

   Example main.py:

   from fastapi import FastAPI
   
   app = FastAPI()
   
   @app.get("/")
   def read_root():
       return {"Hello": "World"}
   

3. Create a Systemd Service for the FastAPI Server: Create /etc/systemd/system/fastapi.service:

   [Unit]
   Description=FastAPI Service
   After=network.target
   
   [Service]
   User=karthik
   Group=karthik
   WorkingDirectory=/home/karthik/Projects/myproject
   ExecStart=/home/karthik/.local/bin/micromamba run -n myenv gunicorn -w 1 -k uvicorn.workers.UvicornWorker main:app -b 127.0.0.1:8000
   Restart=always
   
   [Install]
   WantedBy=multi-user.target
   

4. Enable and Start the Service:

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

Conclusion

You have successfully set up a FastAPI server on a remote machine, configured Nginx as a reverse proxy, and secured it with HTTPS using Certbot. Your FastAPI application is now accessible via your domain over a secure connection.

Feel free to customize your FastAPI application and Nginx configuration further based on your project requirements.

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This tutorial provides a comprehensive guide from setting up basic server access to deploying a FastAPI application with Nginx. Happy coding!