v2.6 Using External Vocabularies

Using External Vocabularies

JSON-LD allows to define classes and properties of your API with open vocabularies such as Schema.org and Good Relations.

API Platform Core provides annotations usable on PHP classes and properties for specifying a related external IRI.

<?php
// api/src/Entity/Book.php

namespace App\Entity;

use ApiPlatform\Core\Annotation\ApiProperty;
use ApiPlatform\Core\Annotation\ApiResource;

#[ApiResource(iri: "https://schema.org/Book")]
class Book
{
    // ...

    #[ApiProperty(iri: "https://schema.org/name")]
    public $name;
    
    // ...
}

The generated JSON for products and the related context document will now use external IRIs according to the specified annotations:

GET /books/22

{
  "@context": "/contexts/Book",
  "@id": "/books/22",
  "@type": "https://schema.org/Book",
  "name": "My awesome book"
}

GET /contexts/Book

{
  "@context": {
    "@vocab": "http://example.com/apidoc#",
    "hydra": "http://www.w3.org/ns/hydra/core#",
    "name": "https://schema.org/name"
  }
}

An extended list of existing open vocabularies is available on the Linked Open Vocabularies (LOV) database.

By default, when using validations API Platform Core will try to define known Schema.org types as IRIs for your properties if you did not provide any in your @ApiProperty annotations. Built-in mapping is:

ConstraintsSchema.org type
Symfony\Component\Validator\Constraints\Urlhttps://schema.org/url
Symfony\Component\Validator\Constraints\Emailhttps://schema.org/email
Symfony\Component\Validator\Constraints\Uuidhttps://schema.org/identifier
Symfony\Component\Validator\Constraints\CardSchemehttps://schema.org/identifier
Symfony\Component\Validator\Constraints\Bichttps://schema.org/identifier
Symfony\Component\Validator\Constraints\Ibanhttps://schema.org/identifier
Symfony\Component\Validator\Constraints\Datehttps://schema.org/Date
Symfony\Component\Validator\Constraints\DateTimehttps://schema.org/DateTime
Symfony\Component\Validator\Constraints\Timehttps://schema.org/Time
Symfony\Component\Validator\Constraints\Imagehttps://schema.org/image
Symfony\Component\Validator\Constraints\Filehttps://schema.org/MediaObject
Symfony\Component\Validator\Constraints\Currencyhttps://schema.org/priceCurrency
Symfony\Component\Validator\Constraints\Isbnhttps://schema.org/isbn
Symfony\Component\Validator\Constraints\Issnhttps://schema.org/issn

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