bensampo/laravel-enum

Simple, extensible and powerful enumeration implementation for Laravel.

1.19 2019-05-10 20:42 UTC

README

Laravel Enum

Build Status Packagist Stable Version Packagist downloads MIT Software License

About Laravel Enum

Simple, extensible and powerful enumeration implementation for Laravel.

  • Enum key value pairs as class constants
  • Full featured suite of methods
  • Enum instantiation
  • Type hinting
  • Attribute casting
  • Enum artisan generator
  • Validation rules for passing enum key or values as input parameters
  • Localization support
  • Extendable via Macros

Created by Ben Sampson

Jump To

Guide

I wrote a blog post about using laravel-enum: https://sampo.co.uk/blog/using-enums-in-laravel

Requirements

  • Laravel 5.4 or newer
  • PHP 7.1 or newer

Installation

Via Composer

$ composer require bensampo/laravel-enum

If you're using Laravel < 5.5 you'll need to add the service provider to config/app.php

'BenSampo\Enum\EnumServiceProvider'

Enum Library

Browse and download from a list of commonly used, community contributed enums.

Enum library →

Basic Usage

Enum Definition

You can use the following Artisan command to generate a new enum class:

php artisan make:enum UserType

Now, you just need to add the possible values your enum can have as constants.

<?php

namespace App\Enums;

use BenSampo\Enum\Enum;

final class UserType extends Enum
{
    const Administrator = 0;
    const Moderator = 1;
    const Subscriber = 2;
    const SuperAdministrator = 3;
}

That's it! Note that because the enum values are defined as plain constants, you can simple access them like any other class constant.

UserType::Administrator // Has a value of 0

Instantiation

It can be useful to instantiate enums in order to pass them between functions with the benefit of type hinting.

Additionally, it's impossible to instantiate an enum with an invalid value, therefore you can be certain that the passed value is always valid.

For convenience, enums can be instantiated in multiple ways:

// Standard new PHP class, passing the desired enum value as a parameter
$enumInstance = new UserType(UserType::Administrator);

// Static getInstance method, again passing the desired enum value as a parameter
$enumInstance = UserType::getInstance(UserType::Administrator);

// Statically calling the key name as a method, utilizing __callStatic magic
$enumInstance = UserType::Administrator();

If you want your IDE to autocomplete the static instantiation helpers, you can generate PHPDoc annotations through an artisan command.

php artisan enum:annotate "App\Enums\UserType"

Instance Properties

Once you have an enum instance, you can access the key, value and description as properties.

$userType = UserType::getInstance(UserType::SuperAdministrator);

$userType->key; // SuperAdministrator
$userType->value; // 0
$userType->description; // Super Administrator

This is particularly useful if you're passing an enum instance to a blade view.

Instance Equality

You can check the equality of an instance against a valid enum value by passing it to the is method.

$userType = UserType::getInstance(UserType::SuperAdministrator);

$userType->is(UserType::SuperAdministrator); // Returns true
$userType->is(UserType::Moderator); // Returns false
$userType->is(UserType::InvalidKey); // Throws InvalidEnumMemberException exception

Type Hinting

One of the benefits of enum instances is that it enables you to use type hinting, as shown below.

function canPerformAction(UserType $userType)
{
    if ($userType->is(UserType::SuperAdministrator)) {
        return true;
    }

    return false;
}

$userType1 = UserType::getInstance(UserType::SuperAdministrator);
$userType2 = UserType::getInstance(UserType::Moderator);

canPerformAction($userType1); // Returns true
canPerformAction($userType2); // Returns false

Attribute Casting

You may cast model attributes to enums using the CastsEnums trait. This will cast the attribute to an enum instance when getting and back to the enum value when setting.

Similar to how standard attribute casting works, you simply define which attributes you want to cast to which enum as an array on the model.

use BenSampo\Enum\Traits\CastsEnums;
use BenSampo\Enum\Tests\Enums\UserType;
use Illuminate\Database\Eloquent\Model;

class Example extends Model
{
    use CastsEnums;
    
    protected $enumCasts = [
        // 'attribute_name' => Enum::class
        'user_type' => UserType::class,
    ];
}

Now, when you access the user_type attribute of your Example model, the underlying value will be returned as a UserType enum.

$example = Example::first();
$example->user_type // Instance of UserType

Review the methods and properties available on enum instances to get the most out of attribute casting.

You can set the value by either passing the enum value or another enum instance.

$example = Example::first();

// Set using enum value
$example->user_type = UserType::Moderator;

// Set using enum instance
$example->user_type = UserType::Moderator();

Validation

Array Validation

You may validate that an enum value passed to a controller is a valid value for a given enum by using the EnumValue rule.

public function store(Request $request)
{
    $this->validate($request, [
        'user_type' => ['required', new EnumValue(UserType::class)],
    ]);
}

By default, type checking is set to strict, but you can bypass this by passing false to the optional second parameter of the EnumValue class.

new EnumValue(UserType::class, false) // Turn off strict type checking.

You can also validate on keys using the EnumKey rule. This is useful if you're taking the enum key as a URL parameter for sorting or filtering for example.

public function store(Request $request)
{
    $this->validate($request, [
        'user_type' => ['required', new EnumKey(UserType::class)],
    ]);
}

Of course, both of these work on form request classes too.

Make sure to include BenSampo\Enum\Rules\EnumValue and/or BenSampo\Enum\Rules\EnumKey and your enum class in the usings.

Pipe Validation

You can also use the 'pipe' syntax for both the EnumKey and EnumValue rules by using enum_value and/or enum_key respectively.

enum_value:enum_class,[strict]
enum_key:enum_class

'user_type' => 'required|enum_value:' . UserType::class,
'user_type' => 'required|enum_key:' . UserType::class,

Localization

You can translate the strings returned by the getDescription method using Laravel's built in localization features.

Add a new enums.php keys file for each of your supported languages. In this example there is one for English and one for Spanish.

// resources/lang/en/enums.php
<?php

use App\Enums\UserType;

return [

    UserType::class => [
        UserType::Administrator => 'Administrator',
        UserType::SuperAdministrator => 'Super administrator',
    ],

];
// resources/lang/es/enums.php
<?php

use App\Enums\UserType;

return [

    UserType::class => [
        UserType::Administrator => 'Administrador',
        UserType::SuperAdministrator => 'Súper administrador',
    ],

];

Now, you just need to make sure that your enum implements the LocalizedEnum interface as demonstrated below:

use BenSampo\Enum\Enum;
use BenSampo\Enum\Contracts\LocalizedEnum;

final class UserType extends Enum implements LocalizedEnum
{
    // ...
}

The getDescription method will now look for the value in your localization files. If a value doesn't exist for a given key, the default description is returned instead.

Overriding the getDescription method

If you'd like to return a custom value from the getDescription method, you may do so by overriding the method on your enum:

public static function getDescription($value): string
{
    if ($value === self::SuperAdministrator) {
        return 'Super admin';
    }

    return parent::getDescription($value);
}

Calling UserType::getDescription(3); now returns Super admin instead of Super administator.

Extending the Enum Base Class

The Enum base class implements the Laravel Macroable trait, meaning it's easy to extend it with your own functions. If you have a function that you often add to each of your enums, you can use a macro.

Let's say we want to be able to get a flipped version of the enum toArray method, we can do this using:

Enum::macro('toFlippedArray', function() {
    return array_flip(self::toArray());
});

Now, on each of my enums, I can call it using UserType::toFlippedArray().

It's best to register the macro inside of a service providers' boot method.

PHPStan integration

If you are using PHPStan for static analysis, you can enable the extension for proper recognition of the magic instantiation methods.

Add the following to your projects phpstan.neon includes:

includes:
- vendor/bensampo/laravel-enum/extension.neon

Enum Class Reference

static getKeys(): array

Returns an array of the keys for an enum.

UserType::getKeys(); // Returns ['Administrator', 'Moderator', 'Subscriber', 'SuperAdministrator']

static getValues(): array

Returns an array of the values for an enum.

UserType::getValues(); // Returns [0, 1, 2, 3]

static getKey(mixed $value): string

Returns the key for the given enum value.

UserType::getKey(1); // Returns 'Moderator'
UserType::getKey(UserType::Moderator); // Returns 'Moderator'

static getValue(string $key): mixed

Returns the value for the given enum key.

UserType::getValue('Moderator'); // Returns 1

static hasKey(string $key): bool

Check if the enum contains a given key.

UserType::hasKey('Moderator'); // Returns 'True'

static hasValue(mixed $value, bool $strict = true): bool

Check if the enum contains a given value.

UserType::hasValue(1); // Returns 'True'

// It's possible to disable the strict type checking:
UserType::hasValue('1'); // Returns 'False'
UserType::hasValue('1', false); // Returns 'True'

static getDescription(mixed $value): string

Returns the key in sentence case for the enum value. It's possible to override the getDescription method to return custom descriptions.

UserType::getDescription(3); // Returns 'Super administrator'
UserType::getDescription(UserType::SuperAdministrator); // Returns 'Super administrator'

static getRandomKey(): string

Returns a random key from the enum. Useful for factories.

UserType::getRandomKey(); // Returns 'Administrator', 'Moderator', 'Subscriber' or 'SuperAdministrator'

static getRandomValue(): mixed

Returns a random value from the enum. Useful for factories.

UserType::getRandomValue(); // Returns 0, 1, 2 or 3

static toArray(): array

Returns the enum key value pairs as an associative array.

UserType::toArray(); // Returns ['Administrator' => 0, 'Moderator' => 1, 'Subscriber' => 2, 'SuperAdministrator' => 3]

static toSelectArray(): array

Returns the enum for use in a select as value => description.

UserType::toSelectArray(); // Returns [0 => 'Administrator', 1 => 'Moderator', 2 => 'Subscriber', 3 => 'Super administrator']

static getInstance(mixed $enumValue): Enum

Returns an instance of the called enum. Read more about enum instantiation.

UserType::getInstance(UserType::Administrator);

static getInstances(): array

Returns an array of all possible instances of the called enum, keyed by the constant names.

var_dump(UserType::getInstances());

array(4) {
  'Administrator' =>
  class BenSampo\Enum\Tests\Enums\UserType#415 (3) {
    public $key =>
    string(13) "Administrator"
    public $value =>
    int(0)
    public $description =>
    string(13) "Administrator"
  }
  'Moderator' =>
  class BenSampo\Enum\Tests\Enums\UserType#396 (3) {
    public $key =>
    string(9) "Moderator"
    public $value =>
    int(1)
    public $description =>
    string(9) "Moderator"
  }
  'Subscriber' =>
  class BenSampo\Enum\Tests\Enums\UserType#393 (3) {
    public $key =>
    string(10) "Subscriber"
    public $value =>
    int(2)
    public $description =>
    string(10) "Subscriber"
  }
  'SuperAdministrator' =>
  class BenSampo\Enum\Tests\Enums\UserType#102 (3) {
    public $key =>
    string(18) "SuperAdministrator"
    public $value =>
    int(3)
    public $description =>
    string(19) "Super administrator"
  }
}