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Laravel Interview Questions

#technology#laravel#php#interview

Updated: 2026-09-24

This cheatsheet collects short answers to Laravel questions that come up in interviews. It starts with four reading links on the service container, dependency injection, and service providers. The question section then moves through CSRF protection, facades, helpers, Artisan, the service container, mail configuration, auth, validation, soft deletes, fillable and guarded fields, caching, Blade syntax, cookie against session, empty against isset, and finally Eloquent against the query builder. Each entry is a definition plus the code or setting you need, so it works as a recall sheet the night before an interview. Skim the headings first, then read only the topics you cannot explain out loud.

Resources

  • Laravel Beauty: Service container
  • Dependency Injection in Laravel
  • Service Container in Laravel
  • Service Provider in Laravel

Questions

CSRF Protection

  • Disable CSRF for a route: Add the URL/route to $except in app\Http\Middleware\VerifyCsrfToken.php

Facade

  • Definition: A class that provides a static interface to services, accessing the service directly from the container
  • Usage: Defined in Illuminate\Support\Facades

Helper

  • Creating a helper: Create app/helpers.php, add it to the composer.json autoload, and run composer dump-autoload

Artisan

  • Definition: Laravel's command line interface, providing many useful commands

Service Container

  • Definition: A tool for managing class dependencies and dependency injection (IoC container)

Mail Configuration

  • Configuration: An API on top of SwiftMailer with drivers (SMTP, Mailgun, SparkPost, Amazon SES)

Auth

  • Definition: Verifies login credentials against the database and manages them through sessions
  • Usage: php artisan make:auth

Validation

  • Definition: Validates incoming data using ValidatesRequests
  • Rules: Alpha, Image, Date, Format, IP Address, URL, Numeric, Email, Size, Min/Max, Unique with database
  • Fluent rule builders (Laravel 13.36+): Rule::requiredWithout('phone'), Rule::url()->protocols(['https']) and others instead of strings. See Laravel Validation Rule Builders

Soft Delete

  • Definition: Soft-deletes records without removing them from the database by setting deleted_at
  • Usage: use Illuminate\Database\Eloquent\SoftDeletes; and use SoftDeletes; in the model

Fillable

  • Definition: An array of fields that can be used to directly create new records (Mass Assignment)

Guarded

  • Definition: The opposite of fillable; fields designated as guarded are not mass assignable

Caching

  • Supported: Memcached and Redis
  • Default: File cache (serialized objects)

Blade Syntax

  • {{ $username }}: Displays text content (HTML escaped)
  • {!! $username !!}: Displays content with HTML tags
  • Cookie: A small file the server embeds on the user's machine, sent with every request
  • Session: Stored on the server, more secure, has a PHP SESSID

empty() vs isset()

  • empty(): Checks for an empty variable, empty array, null, 0
  • isset(): Checks whether a variable exists and whether it is null
  • Comparison: empty covers more cases than isset

Queries in Laravel

  • 2 ways: Eloquent and Query Builder
  • Eloquent: Works through models, supports relationships, code is easier to read
  • Query Builder: Works through the DB layer, can perform most database operations
  • Comparison:
    • Both use PDO parameter binding (preventing SQL injection)
    • All query builder functions can be used in Eloquent, but not the other way around
    • Eloquent cannot perform overly complex queries
  • Usage: Depends on the query; you can combine Eloquent with Query Builder and use DB::raw() for raw SQL

See also: Senior PHP JavaScript Interview · Vuejs Interview Questions