不到 24 小时前，我写了一篇关于如何使用 Cloudflare 缓存加速您的网站的文章。不过，我已经将大部分逻辑转移到使用 Redis 的 Fastify 中间件中。以下是您自己操作的原因和方法。
我遇到了 Cloudflare 缓存的两个问题：
我还遇到了一些其他问题（例如无法使用模式匹配清除缓存），但这些对我的用例来说并不重要。
因此，我决定将逻辑转移到使用 Redis 的 Fastify 中间件。
[！注意]
我将 Cloudflare 缓存留给图像缓存。在这种情况下，Cloudflare 缓存有效地充当 CDN。
下面是我使用 Fastify 编写的用于缓存响应的中间件的带注释版本。
const isCacheableRequest = (request: FastifyRequest): boolean => {
// Do not attempt to use cache for authenticated visitors.
if (request.visitor?.userAccount) {
return false;
}
if (request.method !== 'GET') {
return false;
}
// We only want to cache responses under /supplements/.
if (!request.url.includes('/supplements/')) {
return false;
}
// We provide a mechanism to bypass the cache.
// This is necessary for implementing the "Serve Stale Content While Revalidating" feature.
if (request.headers['cache-control'] === 'no-cache') {
return false;
}
return true;
};
const isCacheableResponse = (reply: FastifyReply): boolean => {
if (reply.statusCode !== 200) {
return false;
}
// We don't want to cache responses that are served from the cache.
if (reply.getHeader('x-pillser-cache') === 'HIT') {
return false;
}
// We only want to cache responses that are HTML.
if (!reply.getHeader('content-type')?.toString().includes('text/html')) {
return false;
}
return true;
};
const generateRequestCacheKey = (request: FastifyRequest): string => {
// We need to namespace the cache key to allow an easy purging of all the cache entries.
return 'request:' + generateHash({
algorithm: 'sha256',
buffer: stringifyJson({
method: request.method,
url: request.url,
// This is used to cache viewport specific responses.
viewportWidth: request.viewportWidth,
}),
encoding: 'hex',
});
};
type CachedResponse = {
body: string;
headers: Record<string, string>;
statusCode: number;
};
const refreshRequestCache = async (request: FastifyRequest) => {
await got({
headers: {
'cache-control': 'no-cache',
'sec-ch-viewport-width': String(request.viewportWidth),
'user-agent': request.headers['user-agent'],
},
method: 'GET',
url: pathToAbsoluteUrl(request.originalUrl),
});
};
app.addHook('onRequest', async (request, reply) => {
if (!isCacheableRequest(request)) {
return;
}
const cachedResponse = await redis.get(generateRequestCacheKey(request));
if (!cachedResponse) {
return;
}
reply.header('x-pillser-cache', 'HIT');
const response: CachedResponse = parseJson(cachedResponse);
reply.status(response.statusCode);
reply.headers(response.headers);
reply.send(response.body);
reply.hijack();
setImmediate(() => {
// After the response is sent, we send a request to refresh the cache in the background.
// This effectively serves stale content while revalidating.
// Therefore, this cache does not reduce the number of requests to the origin;
// The goal is to reduce the response time for the user.
refreshRequestCache(request);
});
});
const readableToString = (readable: Readable): Promise<string> => {
const chunks: Uint8Array[] = [];
return new Promise((resolve, reject) => {
readable.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
readable.on('error', (err) => reject(err));
readable.on('end', () => resolve(Buffer.concat(chunks).toString('utf8')));
});
};
app.addHook('onSend', async (request, reply, payload) => {
if (reply.hasHeader('x-pillser-cache')) {
return payload;
}
if (!isCacheableRequest(request) || !isCacheableResponse(reply) || !(payload instanceof Readable)) {
// Indicate that the response is not cacheable.
reply.header('x-pillser-cache', 'DYNAMIC');
return payload;
}
const content = await readableToString(payload);
const headers = omit(reply.getHeaders(), [
'content-length',
'set-cookie',
'x-pillser-cache',
]) as Record<string, string>;
reply.header('x-pillser-cache', 'MISS');
await redis.setex(
generateRequestCacheKey(request),
getDuration('1 day', 'seconds'),
stringifyJson({
body: content,
headers,
statusCode: reply.statusCode,
} satisfies CachedResponse),
);
return content;
});
注释贯穿了代码，但这里有一些关键点：
我从多个位置运行了延迟测试，并捕获了每个 URL 的最慢响应时间。结果如下：
| URL | Country | Origin Response Time | Cloudflare Cached Response Time | Fastify Cached Response Time |
|---|---|---|---|---|
| https://pillser.com/vitamins/vitamin-b1 | us-west1 | 240ms | 16ms | 40ms |
| https://pillser.com/vitamins/vitamin-b1 | europe-west3 | 320ms | 10ms | 110ms |
| https://pillser.com/vitamins/vitamin-b1 | australia-southeast1 | 362ms | 16ms | 192ms |
| https://pillser.com/supplements/vitamin-b1-3254 | us-west1 | 280ms | 10ms | 38ms |
| https://pillser.com/supplements/vitamin-b1-3254 | europe-west3 | 340ms | 12ms | 141ms |
| https://pillser.com/supplements/vitamin-b1-3254 | australia-southeast1 | 362ms | 14ms | 183ms |
与 Cloudflare 缓存相比，Fastify 缓存速度较慢。这是因为缓存的内容仍然是从源提供的，而 Cloudflare 缓存是从区域边缘位置提供的。然而，我发现这些响应时间足以实现良好的用户体验。
以上是使用 Fastify 和 Redis 缓存加速您的网站的详细内容。更多信息请关注PHP中文网其他相关文章！
