Vercel でホスティングしてる Next.js に Cloudflare の Cache を適用する

export default {
  async fetch(request, env, ctx) {
    const url = new URL(request.url);

    const varyKeys = [
      'RSC', 
      'Next-Router-State-Tree', 
      'Next-Router-Prefetch', 
      'Accept-Encoding',
    ]

    // append these headers to the searchParams in order to distinguish requests with them or not
    for(const key of varyKeys) {
      if (request.headers.has(key) ) {
        url.searchParams.set(key, request.headers.get(key))
      }
    }

    const rewrittenRequest = new Request(url, request);
    let cache = true

    // Do not cache routes starting with `/api`
    if(url.pathname.startsWith('/api')) {
      cache = false;
    }

    let response = await fetch(rewrittenRequest, {
      cf: {
        cacheEverything: cache,
        // only cache 2xx status codes
        cacheTtlByStatus: { 404: 1, "500-599": 0, "300-399": 1 }
      },
    });
    // Reconstruct the Response object to make its headers mutable.
    response = new Response(response.body, response);
    return response;
  },
};

import { NextResponse } from 'next/server';
import { NextRequest } from 'next/server';

export function middleware(request: NextRequest) {
    const url = new URL(request.nextUrl);

    // Check for vary headers appended by cloudfare worker
    const varyKeys = [
        'RSC',
        'Next-Router-State-Tree',
        'Next-Router-Prefetch',
        'Accept-Encoding',
    ];

    let varyFound = false;

    // remove these headers from the URL
    for (const key of varyKeys) {
        if (url.searchParams.has(key)) {
            url.searchParams.delete(key);
            varyFound = true;
        }
    }

    if (varyFound) {
        return NextResponse.rewrite(url);
    }
    return NextResponse.next();
}

export const config = {
    // exclude api, images & static paths (_next/static & _next/image)
    matcher: [
        '/((?!api|_next/static|_next/image|favicon.ico|robots.txt|sitemap.xml).*)',
    ],
};

last-modified: Sun, 03 Mar 2024 15:24:17 GMT
cf-cache-status: HIT
age: 73