Laravel GraphQL

Use Facebook GraphQL with Laravel 5. It is based on the PHP implementation here. You can find more information about GraphQL in the GraphQL Introduction on the React blog or you can read the GraphQL specifications. This is a work in progress.

This package is compatible with Eloquent model (or any other data source). See the example below.

Installation

Dependencies:

• Laravel 5.x
• GraphQL PHP

Installation:

1- Require the package via Composer in your composer.json.

{
	"require": {
		"folklore/graphql": "0.4.*"
	}
}

2- Run Composer to install or update the new requirement.

$ composer install

or

$ composer update

3- Add the service provider to your app/config/app.php file

'Folklore\GraphQL\GraphQLServiceProvider',

4- Add the facade to your app/config/app.php file

'GraphQL' => 'Folklore\GraphQL\Support\Facades\GraphQL',

5- Publish the configuration file

$ php artisan vendor:publish --provider="Folklore\GraphQL\GraphQLServiceProvider"

6- Review the configuration file

config/graphql.php

Usage

• Creating a query
• Creating a mutation
• Adding validation to mutation

Advanced Usage

• Query variables
• Custom field
• Eager loading relationships

Creating a query

First you need to create a type.

	namespace App\GraphQL\Type;
	
	use GraphQL\Type\Definition\Type;
	use Folklore\GraphQL\Support\Type as GraphQLType;
    
    class UserType extends GraphQLType {
        
        protected $attributes = [
			'name' => 'User',
			'description' => 'A user'
		];
		
		public function fields()
		{
			return [
				'id' => [
					'type' => Type::nonNull(Type::string()),
					'description' => 'The id of the user'
				],
				'email' => [
					'type' => Type::string(),
					'description' => 'The email of user'
				]
			];
		}
			
			
		// If you want to resolve the field yourself, you can declare a method
		// with the following format resolve[FIELD_NAME]Field()
		protected function resolveEmailField($root, $args)
		{
			return strtolower($root->email);
		}
        
    }

Add the type to the config/graphql.php configuration file

    
	'types' => [
		'user' => 'App\GraphQL\Type\UserType'
	]

You could also add the type with the GraphQL Facade, in a service provider for example.

    
	GraphQL::addType('App\GraphQL\Type\UserType', 'user');

Then you need to define a query that returns this type (or a list). You can also specify arguments that you can use in the resolve method.

	namespace App\GraphQL\Query;
	
	use GraphQL;
	use GraphQL\Type\Definition\Type;
	use Folklore\GraphQL\Support\Query;    
	use App\User;
	
	class UsersQuery extends Query {
	
		protected $attributes = [
			'name' => 'Users query'
		];
		
		public function type()
		{
			return Type::listOf(GraphQL::type('user'));
		}
		
		public function args()
		{
			return [
				'id' => ['name' => 'id', 'type' => Type::string()],
				'email' => ['name' => 'email', 'type' => Type::string()]
			];
		}
		
		public function resolve($root, $args)
		{
			if(isset($args['id']))
			{
				return User::where('id' , $args['id'])->get();
			}
			else if(isset($args['email']))
			{
				return User::where('email', $args['email'])->get();
			}
			else
			{
				return User::all();
			}
		}
	
	}

Add the query to the config/graphql.php configuration file

    
    'schema' => [
		'query' => [
			'users' => 'App\GraphQL\Query\UsersQuery'
		],
		// ...
	]

Or using the GraphQL facade

    
    GraphQL::addQuery('App\GraphQL\Query\UsersQuery', 'users');

And that's it. You should be able to query GraphQL with a request to the url /graphql (or anything you choose in your config). Try a GET request with the following query input

    query FetchUsers {
        users {
            id
            email
        }
    }

For example, if you use homestead:

http://homestead.app/graphql?query=query+FetchUsers{users{id,email}}

Creating a mutation

A mutation is like any other query, it accepts arguments (which will be used to do the mutation) and return an object of a certain type.

For example a mutation to update the password of a user. First you need to define the Mutation.

	namespace App\GraphQL\Mutation;
	
	use GraphQL;
	use GraphQL\Type\Definition\Type;
	use Folklore\GraphQL\Support\Mutation;    
	use App\User;
	
	class UpdateUserPasswordMutation extends Mutation {
	
		protected $attributes = [
			'name' => 'UpdateUserPassword'
		];
		
		public function type()
		{
			return GraphQL::type('user');
		}
		
		public function args()
		{
			return [
				'id' => ['name' => 'id', 'type' => Type::nonNull(Type::string())],
				'password' => ['name' => 'password', 'type' => Type::nonNull(Type::string())]
			];
		}
		
		public function resolve($root, $args)
		{
			$user = User::find($args['id']);
			if(!$user)
			{
				return null;
			}
			
			$user->password = bcrypt($args['password']);
			$user->save();
			
			return $user;
		}
	
	}

As you can see in the resolve method, you use the arguments to update your model and return it.

You then add the muation to the config/graphql.php configuration file

    
    'schema' => [
		'mutation' => [
			'updateUserPassword' => 'App\GraphQL\Mutation\UpdateUserPasswordMutation'
		],
		// ...
	]

Or using the GraphQL facade

    
    GraphQL::addMutation('App\GraphQL\Mutation\UpdateUserPasswordMutation', 'updateUserPassword');

You should then be able to use the following query on your endpoint to do the mutation.

    mutation {
        updateUserPassword(id: "1", password: "newpassword") {
            id
            email
        }
    }

Adding validation to mutation

It is possible to add validation rules to mutation. It uses the laravel Validator to performs validation against the args.

When creating a mutation, you can add a method to define the validation rules that apply by doing the following:

	namespace App\GraphQL\Mutation;
	
	use GraphQL;
	use GraphQL\Type\Definition\Type;
	use Folklore\GraphQL\Support\Mutation;    
	use App\User;
	
	class UpdateUserEmailMutation extends Mutation {
	
		protected $attributes = [
			'name' => 'UpdateUserEmail'
		];
		
		public function type()
		{
			return GraphQL::type('user');
		}
		
		public function args()
		{
			return [
				'id' => ['name' => 'id', 'type' => Type::string()],
				'email' => ['name' => 'password', 'type' => Type::string()]
			];
		}
		
		public function rules()
		{
			return [
				'id' => ['required'],
				'email' => ['required', 'email']
			];
		}
		
		public function resolve($root, $args)
		{
			$user = User::find($args['id']);
			if(!$user)
			{
				return null;
			}
			
			$user->email = $args['email'];
			$user->save();
			
			return $user;
		}
	
	}

Alternatively you can define rules with each args

	
	class UpdateUserEmailMutation extends Mutation {
	
		//...
		
		public function args()
		{
			return [
				'id' => [
					'name' => 'id',
					'type' => Type::string(),
					'rules' => ['required']
				],
				'email' => [
					'name' => 'password',
					'type' => Type::string(),
					'rules' => ['required', 'email']
				]
			];
		}
		
		//...
	
	}

When you execute a mutation, it will returns the validation errors. Since GraphQL specifications define a certain format for errors, the validation errors messages are added to the error object as a extra validation attribute. To find the validation error, you should check for the error with a message equals to 'validation', then the validation attribute will contain the normal errors messages returned by the Laravel Validator.

	{
		"data": {
			"updateUserEmail": null
		},
		"errors": [
			{
				"message": "validation",
				"locations": [
					{
						"line": 1,
						"column": 20
					}
				],
				"validation": {
					"email": [
						"The email is invalid."
					]
				}
			}
		]
	}

Advanced usage

Query Variables

GraphQL offer you the possibility to use variables in your query so you don't need to "hardcode" value. This is done like that:

    query FetchUserByID($id: String) {
        user(id: $id) {
            id
            email
        }
    }

When you query the GraphQL endpoint, you can pass a params parameter.

http://homestead.app/graphql?query=query+FetchUserByID($id:String){user(id:$id){id,email}}&params={"id":"1"}

Custom field

You can also define a field as a class if you want to reuse it in multiple types.

namespace App\GraphQL\Fields;
	
use GraphQL\Type\Definition\Type;
use Folklore\GraphQL\Support\Field;

class PictureField extends Field {
        
        protected $attributes = [
		'description' => 'A picture'
	];
		
	public function args()
	{
		return [
			'width' => [
				'type' => Type::int(),
				'description' => 'The width of the picture'
			],
			'height' => [
				'type' => Type::int(),
				'description' => 'The height of the picture'
			]
		];
	}
	
	protected function resolve($root, $args)
	{
		$width = isset($args['width']) ? $args['width']:100;
		$height = isset($args['height']) ? $args['height']:100;
		return 'http://placehold.it/'.$width.'x'.$height;
	}
        
}

You can then use it in your type declaration

namespace App\GraphQL\Type;

use GraphQL\Type\Definition\Type;
use Folklore\GraphQL\Support\Type as GraphQLType;

class UserType extends GraphQLType {
        
        protected $attributes = [
		'name' => 'User',
		'description' => 'A user'
	];
	
	public function fields()
	{
		return [
			'id' => [
				'type' => Type::nonNull(Type::string()),
				'description' => 'The id of the user'
			],
			'email' => [
				'type' => Type::string(),
				'description' => 'The email of user'
			],
			//Instead of passing an array, you pass a class path to your custom field
			'picture' => App\GraphQL\Fields\PictureField::class
		];
	}

}

Eager loading relationships

The third argument passed to a query's resolve method is an instance of GraphQL\Type\Definition\ResolveInfo which you can use to retrieve keys from the request. The following is an example of using this information to eager load related Eloquent models.

Your Query would look like

	namespace App\GraphQL\Query;
	
	use GraphQL;
	use GraphQL\Type\Definition\Type;
	use GraphQL\Type\Definition\ResolveInfo;
	use Folklore\GraphQL\Support\Query;
	
	use App\User;

	class UsersQuery extends Query
	{
		protected $attributes = [
			'name' => 'Users query'
		];

		public function type()
		{
			return Type::listOf(GraphQL::type('user'));
		}

		public function args()
		{
			return [
				'id' => ['name' => 'id', 'type' => Type::string()],
				'email' => ['name' => 'email', 'type' => Type::string()]
			];
		}
        
		public function resolve($root, $args, ResolveInfo $info)
		{
			$fields = $info->getFieldSelection($depth = 3);
			
			$users = User::query();
			
			foreach ($fields as $field => $keys) {
				if ($field === 'profile') {
					$users->with('profile');
				}
				
				if ($field === 'posts') {
					$users->with('posts');
				}
			}
			
			return $users->get();
		}
	}

Your Type for User would look like

<?php

namespace App\GraphQL\Type;

use Folklore\GraphQL\Support\Facades\GraphQL;
use GraphQL\Type\Definition\Type;
use Folklore\GraphQL\Support\Type as GraphQLType;

class UserType extends GraphQLType
{
    /**
     * @var array
     */
    protected $attributes = [
        'name' => 'User',
        'description' => 'A user',
    ];

    /**
     * @return array
     */
    public function fields()
    {
        return [
            'uuid' => [
                'type' => Type::nonNull(Type::string()),
                'description' => 'The uuid of the user'
            ],
            'email' => [
                'type' => Type::nonNull(Type::string()),
                'description' => 'The email of user'
            ],
            'profile' => [
                'type' => GraphQL::type('Profile'),
                'description' => 'The user profile',
            ],
            'posts' => [
                'type' => Type::listOf(GraphQL::type('Post')),
                'description' => 'The user posts',
            ]
        ];
    }
}

At this point we have a profile and a post type as expected for any model

class ProfileType extends GraphQLType
{
    protected $attributes = [
        'name' => 'Profile',
        'description' => 'A user profile',
    ];

    public function fields()
    {
        return [
            'name' => [
                'type' => Type::string(),
                'description' => 'The name of user'
            ]
        ];
    }
}

class PostType extends GraphQLType
{
    protected $attributes = [
        'name' => 'Post',
        'description' => 'A post',
    ];

    public function fields()
    {
        return [
            'title' => [
                'type' => Type::nonNull(Type::string()),
                'description' => 'The title of the post'
            ],
            'body' => [
                'type' => Type::string(),
                'description' => 'The body the post'
            ]
        ];
    }
}

Lastly your query would look like, if using Homestead

For example, if you use homestead:

http://homestead.app/graphql?query=query+FetchUsers{users{uuid, email, team{name}}}