Code Explainers

Php code explainers

php 
public function importCustomers(UploadedFile $file): array
{
    $errors = [];
    $imported = 0;

Validating a CSV import in Laravel

csv-parsing validation error-accumulation
Intermediate 8 steps
php 
<?php
 
final class OrderRepository
{

Atomic order placement with PDO transactions

transactions prepared-statements atomicity
Intermediate 8 steps
php 
<?php
 
function buildTree(array $items, ?int $parentId = null): array
{

Building a tree from a flat list in PHP

recursion tree grouping
Intermediate 6 steps
php 
final class ConfigResolver
{
    private array $merged;
 

Layered config merging in PHP

recursion immutability variadics
Intermediate 8 steps
php 
<?php
 
function uploadDocument(string $endpoint, string $filePath, array $meta): array
{

Uploading a file with cURL in PHP

curl file-upload http
Intermediate 8 steps
php 
<?php
 
namespace App\Console\Commands;
 

Streaming CSV imports in Laravel

lazy-evaluation generators batch-processing
Intermediate 7 steps
php 
<?php
 
namespace App\Services;
 

Resilient HTTP retries with Laravel's client

http-client retry-logic error-handling
Intermediate 7 steps
php 
<?php
 
namespace App\Services;
 

Building signed, expiring download URLs in PHP in Laravel

hmac url-signing authentication
Intermediate 7 steps
php 
<?php
 
declare(strict_types=1);
 

A single-action JSON user controller in PHP

invokable-class json-api validation
Intermediate 7 steps
php 
<?php
 
namespace App\Services\Provisioning;
 

Sequencing site setup with Laravel job chains

job chains queues async workflows
Intermediate 6 steps
php 
final class UserActivityStream
{
    public function __construct(
        private readonly \PDO $db,

Streaming user activity with PHP generators

generators pagination lazy-evaluation
Intermediate 8 steps
php 
<?php
 
namespace App\Casts;
 

How a custom Eloquent cast wraps an Address in Laravel

value-objects serialization data-mapping
Intermediate 7 steps
php 
use Illuminate\Support\Facades\Route;
use App\Http\Controllers\Admin\DashboardController;
use App\Http\Controllers\Admin\UserController;
use App\Http\Controllers\Admin\ReportController;

How nested route groups compose in Laravel

routing middleware authorization
Intermediate 8 steps
php 
final class TokenBucketLimiter
{
    private float $tokens;
    private float $lastRefill;

How a token bucket rate limiter works

rate-limiting token-bucket throttling
Intermediate 7 steps
php 
<?php
 
namespace App\Events;
 

How a broadcast event works in Laravel

broadcasting websockets events
Intermediate 5 steps
php 
<?php
 
final class UserRepository
{

A safe PDO user repository in PHP

prepared-statements repository-pattern sql-injection
Intermediate 7 steps
php 
<?php
 
namespace App\Services;
 

Caching tenant dashboard metrics in Laravel

caching multi-tenancy aggregation
Intermediate 7 steps
php 
<?php
 
namespace App\Http\Controllers\Auth;
 

Rate-limited login in Laravel

authentication rate-limiting validation
Intermediate 9 steps