Building production applications in Django requires robust system knowledge. If you are preparing for code reviews or technical job applications, these core architecture answers will make your solutions stand out.
1. Understanding Django Middleware Architecture
Middleware is a framework of hooks into Django's request/response processing. It’s a light, low-level “plugin” system for globally altering Django’s input or output. Common use cases include user session handling, request authentication, or setting specific tracking details securely on active user sessions before view logic processes them.
"Always ensure your custom middleware returns an HttpResponse or delegates safely to subsequent processing levels."
2. Optimizing Database Hits (select_related vs prefetch_related)
Database queries inside loops are performance killers.
Django offers select_related for
Forward/OneToOne relationships by doing a SQL JOIN
operation. For reverse lookups or ManyToMany models, use
prefetch_related which runs a clean
secondary evaluation block and resolves references via
Python memory structures seamlessly.