How NGINX Acts as a Gateway to Route Traffic Between Docker Containers

In a typical containerised web application, NGINX serves as the sole internet-facing entry point, routing incoming browser requests to the appropriate internal Docker containers. When a user visits a site, DNS resolves the domain to the server's public IP, and NGINX receives the request before any other service does. Requests to the root path are forwarded to the frontend container, while paths beginning with '/api' are directed to the backend service. The backend processes logic and queries a PostgreSQL database, which remains entirely hidden from the public internet. This architecture keeps internal services isolated within Docker's private network, improving both security and maintainability.