nginx.conf

events {
    worker_connections 1024;
}

http {
    include mime.types;
    default_type application/octet-stream;

    sendfile on;
    keepalive_timeout 65;

    # Gzip settings (optional, but good for performance)
    gzip on;
    gzip_vary on;
    gzip_proxied any;
    gzip_comp_level 6;
    gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

    server {
        listen 7860; # Hugging Face Spaces default port for Docker SDK
        server_name localhost;

        # Serve Streamlit app at the root (/)
        location / {
            proxy_pass http://localhost:8501; # Streamlit's default port
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection "upgrade";
            proxy_set_header Host $host;
            proxy_cache_bypass $http_upgrade;
            proxy_read_timeout 300s; # Increase if Streamlit app takes long to load/respond
            proxy_send_timeout 300s;
        }

        # Serve Flask API at /api/ (or adjust as per your Flask app's routing)
        # Note: Your Streamlit app should call http://localhost:5000/preprocess/upload etc. internally.
        # This Nginx block is for if you wanted to expose Flask directly under /api/,
        # but for internal communication, Streamlit calls Flask's internal port directly.
        # However, for the Streamlit app to communicate with Flask, it *must* use `http://localhost:5000`.
        # The Nginx here is primarily for serving the Streamlit app to the public.
        # If your Streamlit app's FLASK_API_URL is "http://localhost:5000", Nginx doesn't mediate these internal calls.
        # The Nginx config below is for direct external access to Flask, which is usually not needed when Streamlit is the frontend.
        # I'll keep it simple for now, focusing on Streamlit at root.

        # If you wanted to expose Flask on a subpath of the Space URL (e.g., yourspace.hf.space/flask_api)
        # you would add a location block like this, but your Streamlit app would still call localhost:5000 internally.
        # location /flask_api/ {
        #     proxy_pass http://localhost:5000/;
        #     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;
        # }
    }
}