php 45 lines · 9 steps

Building a filtered product index in Laravel

How Eloquent's when() method conditionally chains query filters from validated request input.

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Laravel Intermediate query-builder validation conditional-queries pagination closures

1<?php
2 
3namespace App\Http\Controllers;
4 
5use App\Models\Product;
6use Illuminate\Http\Request;
7 
8class ProductController extends Controller
9{
  public function index(Request $request)
  {
      $filters = $request->validate([
          'search' => ['nullable', 'string', 'max:255'],
          'category_id' => ['nullable', 'integer', 'exists:categories,id'],
          'min_price' => ['nullable', 'numeric', 'min:0'],
          'max_price' => ['nullable', 'numeric', 'gte:min_price'],
          'in_stock' => ['nullable', 'boolean'],
          'sort' => ['nullable', 'in:newest,price_asc,price_desc'],
      ]);
20 
      $products = Product::query()
          ->with('category')
          ->when($filters['search'] ?? null, function ($query, $search) {
              $query->where(function ($q) use ($search) {
                  $q->where('name', 'like', "%{$search}%")
                      ->orWhere('sku', 'like', "%{$search}%");
              });
          })
          ->when($filters['category_id'] ?? null, fn ($query, $id) => $query->where('category_id', $id))
          ->when($filters['min_price'] ?? null, fn ($query, $min) => $query->where('price', '>=', $min))
          ->when($filters['max_price'] ?? null, fn ($query, $max) => $query->where('price', '<=', $max))
          ->when($request->boolean('in_stock'), fn ($query) => $query->where('stock', '>', 0))
          ->when($filters['sort'] ?? 'newest', function ($query, $sort) {
              match ($sort) {
                  'price_asc' => $query->orderBy('price'),
                  'price_desc' => $query->orderByDesc('price'),
                  default => $query->latest(),
              };
          })
          ->paginate(24)
          ->withQueryString();
42 
      return view('products.index', compact('products', 'filters'));
  }
45}

01 / 01

STEP 01

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Three takeaways

1Validating request input up front turns untrusted query parameters into a safe, typed array you can trust downstream.
2when() lets you assemble a query conditionally without a tangle of if statements, applying each filter only when its value is present.
3Pairing paginate() with withQueryString() keeps active filters intact as users move between pages.

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