php-json-schema

A PHP implementation of JSON Schema. This library allows you to create JSON Schema objects and validate JSON data against them.

Installation

Install the latest version with

composer require knplabs/php-json-schema

Basic Usage

A JsonSchema must implements KnpLabs\JsonSchema\JsonSchemaInterface (which also extends JsonSerializable).

Default JsonSchema

There is already a default implementation of JsonSchemaInterface called KnpLabs\JsonSchema\JsonSchema which is an abstract class. This class provides some static methods to create some common JSON Schema scalars or objects.

Scalars

JsonSchema::string()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'firstName',                       // The name of the property
    'Hold the first name of the user', // The description of the property
    ['John', 'Georges'],               // Some examples of possible values
    JsonSchema::string()               // The type of the property
);

JsonSchema::text()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'content',                    // The name of the property
    'The content of the article', // The description of the property
    ['Lorem ipsum...'],           // Some examples of possible values
    JsonSchema::text()            // The type of the property
);

JsonSchema::integer()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'age',                            // The name of the property
    'Hold the age of the user',       // The description of the property
    [25, 30],                         // Some examples of possible values
    JsonSchema::integer()             // The type of the property
);

JsonSchema::positiveInteger()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'age',                            // The name of the property
    'Hold the age of the user',       // The description of the property
    [25, 30],                         // Some examples of possible values
    JsonSchema::positiveInteger()     // The type of the property
);

JsonSchema::number()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'price',                // The name of the property
    'The price in dollars', // The description of the property
    [10.8, 30.0],           // Some examples of possible values
    JsonSchema::number()    // The type of the property
);

JsonSchema::boolean()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'isAdult',                      // The name of the property
    'Hold if the user is an adult', // The description of the property
    [true, false],                  // Some examples of possible values
    JsonSchema::boolean()           // The type of the property
);

JsonSchema::date()

use KnpLabs\JsonSchema\JsonSchema;

$schema = JsonSchema::create(
    'createdAt',                    // The name of the property
    'The date of creation',         // The description of the property
    ['2015-01-01', '2015-01-02'],   // Some examples of possible values
    JsonSchema::date()              // The type of the property
);

Enum

Enum is a special type of scalar which is a list of possible values. They can be created by extending the KnpLabs\JsonSchema\EnumSchema:

<?php

namespace Acme;

use KnpLabs\JsonSchema\EnumSchema;

class RoleEnum extends EnumSchema
{
    const ROLE_ADMIN = 'ROLE_ADMIN';
    const ROLE_USER = 'ROLE_USER';

    public function getTitle(): string
    {
        return 'Role enum';
    }

    public function getDescription(): string
    {
        return 'Enum of the possible roles';
    }

    public static function getEnum()
    {
        yield self::ROLE_ADMIN;
        yield self::ROLE_USER;
    }
}

Objects

You can create objects schema by extending the KnpLabs\JsonSchema\ObjectSchema class:

<?php

namespace Acme;

use KnpLabs\JsonSchema\ObjectSchema;

/**
 * @extends ObjectSchema<array{
 *   firstName: string,
 *   lastName: string,
 *   role: string,
 * }>
 */
class PersonSchema extends ObjectSchema
{
    public function __construct()
    {
        $this->addProperty(
            'firstName',
            JsonSchema::create(
                'firstName',
                'Hold the first name of the user',
                ['John', 'Georges'],
                JsonSchema::string()
            )
        );

        $this->addProperty(
            'lastName',
            JsonSchema::create(
                'lastName',
                'Hold the last name of the user',
                ['Doe', 'Smith'],
                JsonSchema::string()
            )
        );

        $this->addProperty('role', new RoleEnum());
    }
}

Collections

You can create collections schema by extending the KnpLabs\JsonSchema\CollectionSchema class:

<?php

namespace Acme;

use KnpLabs\JsonSchema\CollectionSchema;

class PersonCollectionSchema extends CollectionSchema
{
    public function __construct()
    {
        parent::__construct(new PersonSchema());
    }

    public function getDescription(): string
    {
        return 'The list of all the persons';
    }
}