Inertia Rails Controllers Server-side patterns for Rails controllers serving Inertia responses. Before adding a prop, ask: - Needed on every page? → in a base controller ( ), not a per-action prop - Expensive to compute? → — page loads fast, data streams in after - Only needed on partial reload? → — skipped on initial load - Reference data that rarely changes? → — cached across navigations NEVER: - Use for external URLs (Stripe, OAuth, SSO) — it returns 302 but the Inertia client tries to parse the response as JSON, causing a broken redirect. Use (returns 409 + header). - Use for validation e…