Laravel Eloquent: Serializing Models and Collections to Arrays and JSON, Hiding Attributes, Appending Values, and Custom Date Formats

Serializing Models & Collections

To convert a model and its loaded relationships to an array, use the toArray method, which recursively includes all attributes and nested relations.

$user = App\User::with('roles')->first();
return $user->toArray();

You can also convert an entire collection to an array:

$users = App\User::all();
return $users->toArray();

Serializing to JSON

The toJson method converts a model to JSON and works like toArray but returns a JSON string. The method is recursive, so all attributes and relations are included.

$user = App\User::find(1);
return $user->toJson();

When a model or collection is cast to a string, Laravel automatically calls toJson:

$user = App\User::find(1);
return (string) $user;

Because of this behavior, you can return an Eloquent object directly from a route or controller:

Route::get('users', function () {
    return App\User::all();
});

Hiding JSON Attributes

To hide certain attributes (e.g., passwords) from the serialized output, define a $hidden property on the model:

<?php
namespace App;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    /**
     * Attributes that should be hidden
     *
     * @var array
     */
    protected $hidden = ['password'];
}

{note} To hide relationships, use the relationship method name.

Alternatively, you can define a whitelist of visible attributes with $visible:

<?php
namespace App;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    /**
     * Attributes that should be visible
     *
     * @var array
     */
    protected $visible = ['first_name', 'last_name'];
}

Temporarily Modifying Visibility

Use makeVisible to temporarily expose hidden attributes, returning a model instance:

return $user->makeVisible('attribute')->toArray();

Use makeHidden to temporarily hide visible attributes:

return $user->makeHidden('attribute')->toArray();

Appending JSON Values

To add computed attributes that do not exist in the database, define an accessor and list the attribute name in the $appends array:

<?php
namespace App;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    /**
     * Get admin flag for the user
     *
     * @return bool
     */
    public function getIsAdminAttribute()
    {
        return $this->attributes['admin'] == 'yes';
    }
}

Then add the accessor name (snake_case) to $appends:

<?php
namespace App;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    /**
     * Attributes to append to the model's array form
     *
     * @var array
     */
    protected $appends = ['is_admin'];
}

At runtime you can also append attributes on a single model instance using append or replace the entire list with setAppends:

return $user->append('is_admin')->toArray();
return $user->setAppends(['is_admin'])->toArray();

Serializing Dates

Custom Date Formats for Specific Attributes

Define custom formats for date attributes in the model's $casts array:

protected $casts = [
    'birthday' => 'date:Y-m-d',
    'joined_at' => 'datetime:Y-m-d H:00',
];

Global Carbon Serialization

Laravel extends the Carbon library; you can globally customize how Carbon dates are serialized by using Carbon::serializeUsing in a service provider:

<?php
namespace App\Providers;

use Illuminate\Support\Carbon;
use Illuminate\Support\ServiceProvider;

class AppServiceProvider extends ServiceProvider
{
    public function boot()
    {
        Carbon::serializeUsing(function ($carbon) {
            return $carbon->format('U');
        });
    }

    public function register()
    {
        //
    }
}