net/http

Canonical guidance

• start with net/http
• handlers should be small and explicit about request-scoped work
• propagate request context through downstream calls
• configure server and client timeouts deliberately

Use when

• building APIs
• middleware design
• HTTP clients and servers

Avoid

• global shared request state
• ignoring request context
• default timeouts everywhere in production network code

Preferred pattern

func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	if err := s.handle(r.Context(), w, r); err != nil {
		http.Error(w, "internal error", http.StatusInternalServerError)
	}
}

Anti-pattern

• handlers that spawn detached goroutines with request-owned resources

Explanation: This anti-pattern is tempting when handlers need to keep work running, but detached goroutines often retain request-owned resources after the caller is gone.

Why

• the standard library already encodes the dominant Go HTTP model
• many correctness bugs here are lifecycle and timeout bugs, not routing bugs