php 45 lines · 8 steps

Caching HTTP responses with Laravel middleware

A middleware that serves cached responses for safe GET requests and stores fresh ones on the way out.

Explained by highlit

Laravel Intermediate middleware caching http ttl

1<?php
2 
3namespace App\Http\Middleware;
4 
5use Closure;
6use Illuminate\Http\Request;
7use Illuminate\Support\Facades\Cache;
8use Symfony\Component\HttpFoundation\Response;
9 
10class CacheResponse
11{
12    public function handle(Request $request, Closure $next, int $ttl = 300): Response
13    {
14        if (! $request->isMethod('GET') || $request->hasHeader('Authorization')) {
15            return $next($request);
16        }
17 
18        $key = $this->cacheKey($request);
19 
20        if ($cached = Cache::get($key)) {
21            return response($cached['content'], $cached['status'])
22                ->withHeaders($cached['headers'])
23                ->header('X-Cache', 'HIT');
24        }
25 
26        $response = $next($request);
27 
28        if ($response->isSuccessful()) {
29            Cache::put($key, [
30                'content' => $response->getContent(),
31                'status' => $response->getStatusCode(),
32                'headers' => [
33                    'Content-Type' => $response->headers->get('Content-Type'),
34                ],
35            ], now()->addSeconds($ttl));
36        }
37 
38        return $response->header('X-Cache', 'MISS');
39    }
40 
41    protected function cacheKey(Request $request): string
42    {
43        return 'response:'.sha1($request->fullUrl());
44    }
45}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1Only cache idempotent, unauthenticated requests to avoid serving one user's data to another.
2An X-Cache header makes it easy to verify hits versus misses in production.
3Storing status, content, and headers together lets you faithfully reconstruct a response from cache.

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