ae39e45460
NOVAS SKILLS: - next-best-practices v0.1.0 (CLEAN) — Next.js App Router, RSC, caching, data - nextjs-patterns v1.0.0 (CLEAN) — Next.js 15: Server Actions, route handlers - vite v1.0.0 (CLEAN) — env vars, aliases, proxy, CJS compat - uncle-bob v1.0.0 (CLEAN) — Clean Code, SOLID, Clean Architecture - clean-code-review v1.0.0 (CLEAN) — naming, guard clauses, anti-patterns, refactoring - vue v1.0.0 (CLEAN) — Vue framework - vue-composition-api-best-practices v1.0.0 (CLEAN) — composables, Pinia, reactivity BIBLIOTECA INTELIGENTE libs/ (10 dominios, 11 arquivos): - typescript/ — TS safe + generics gotchas - react/ — Next.js App Router + Vite config - vue/ — Composition API + Pinia - linux/ — System diagnostic cheatsheet - database/ — PostgreSQL + MySQL patterns - browser/ — Chromium CLI + E2E testing - security/ — SAST audit (OWASP Top 10) - best-practices/ — Clean Code + SOLID + Clean Architecture - deploy/ — Docker multi-stack + OpenClaw ops - + INDEX.md como guia de navegacao .learnings/ — LRN-20260519-003 criado (biblioteca compartilhada)
2.3 KiB
2.3 KiB
Next.js 15 Caching Deep Dive
The Four Caching Layers
1. Request Memoization (in-memory, per request)
Automatically deduplicates identical fetch() calls within a single render tree.
// Both components call fetchUser(id) — only ONE network request is made
async function Avatar({ id }) { const u = await fetchUser(id); return <img src={u.avatar} /> }
async function Name({ id }) { const u = await fetchUser(id); return <span>{u.name}</span> }
2. Data Cache (persistent, cross-request)
fetch() responses are stored on the server and reused across requests and deployments.
// Static — cached indefinitely
fetch(url)
fetch(url, { cache: "force-cache" })
// Time-based revalidation (ISR)
fetch(url, { next: { revalidate: 3600 } }) // revalidate every hour
// Always fresh — no caching
fetch(url, { cache: "no-store" })
fetch(url, { next: { revalidate: 0 } })
3. Full Route Cache (build-time static rendering)
Pages rendered at build time are stored as static HTML+RSC payload.
// Force dynamic rendering for this route
export const dynamic = "force-dynamic"
// Custom revalidation period for the whole route
export const revalidate = 60
4. Router Cache (client-side, per session)
Browser caches RSC payloads for instant back/forward navigation.
- Static routes: cached for 5 minutes
- Dynamic routes: cached for 30 seconds
On-Demand Revalidation
// Revalidate by path
import { revalidatePath } from "next/cache"
revalidatePath("/blog")
revalidatePath("/blog/[slug]", "page")
// Revalidate by cache tag
import { revalidateTag } from "next/cache"
revalidateTag("posts")
// Tagging fetches
fetch(url, { next: { tags: ["posts"] } })
unstable_cache for Non-Fetch Data
import { unstable_cache } from "next/cache"
const getCachedUser = unstable_cache(
async (id: string) => db.user.findUnique({ where: { id } }),
["user"],
{ revalidate: 300, tags: ["users"] }
)
Common Pitfalls
| Mistake | Fix |
|---|---|
Using fetch inside useEffect |
Move to Server Component or use React Query |
Forgetting revalidatePath after mutations |
Call in Server Action after every write |
| Over-caching user-specific data | Add cache: "no-store" or check cookies()/headers() |
| Sequential awaits | Use Promise.all() for parallel fetching |