v2.1 Swagger / Open API Support

Swagger / Open API Support

API Platform natively support the Open API (formerly Swagger) API documentation format. It also integrates a customized version of Swagger UI, a nice tool to display the API documentation in a user friendly way.

Screenshot

Overriding the Swagger Documentation

Symfony allows to decorate services, here we need to decorate api_platform.swagger.normalizer.documentation.

In the following example, we will see how to override the title of the Swagger documentation and add a custom filter for the GET operation of /foos path

# app/config/services.yml
services:
    'AppBundle\Swagger\SwaggerDecorator':
        decorates: 'api_platform.swagger.normalizer.documentation'
        arguments: [ '@AppBundle\Swagger\SwaggerDecorator.inner' ]
        autoconfigure: false
<?php
// src/AppBundle/Swagger/SwaggerDecorator.php

namespace AppBundle\Swagger;

use Symfony\Component\Serializer\Normalizer\NormalizerInterface;

final class SwaggerDecorator implements NormalizerInterface
{
    private $decorated;

    public function __construct(NormalizerInterface $decorated)
    {
        $this->decorated = $decorated;
    }

    public function normalize($object, $format = null, array $context = [])
    {
        $docs = $this->decorated->normalize($object, $format, $context);

        $customDefinition = [
            'name' => 'fields',
            'definition' => 'Fields to remove of the outpout',
            'default' => 'id',
            'in' => 'query',
        ];


	// e.g. add a custom parameter
	$docs['paths']['/foos']['get']['parameters'][] = $customDefinition;

	// Override title
	$docs['info']['title'] = 'My Api Foo';

        return $docs;
    }

    public function supportsNormalization($data, $format = null)
    {
        return $this->decorated->supportsNormalization($data, $format);
    }
}

Using the Swagger Context

Sometimes you may want to have additional information included in your Swagger documentation. The following configuration will provide additional context to your Swagger definitions:

<?php
// src/AppBundle/Entity/Product.php

namespace AppBundle\Entity;

use ApiPlatform\Core\Annotation\ApiResource;
use ApiPlatform\Core\Annotation\ApiProperty;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

/**
 * @ApiResource
 * @ORM\Entity
 */
class Product // The class name will be used to name exposed resources
{
    /**
     * @ORM\Column(type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    public $id;

    /**
     * @param string $name A name property - this description will be avaliable in the API documentation too.
     *
     * @ORM\Column
     * @Assert\NotBlank
     *
     * @ApiProperty(
     *     attributes={
     *         "swagger_context"={
     *             "type"="string",
     *             "enum"={"one", "two"},
     *             "example"="one"          
     *         }
     *     }
     * )
     */
    public $name;

    /**
     * @ORM\Column
     * @Assert\DateTime
     *
     * @ApiProperty(
     *     attributes={
     *         "swagger_context"={"type"="string", "format"="date-time"}
     *     }
     * )
     */
    public $timestamp;
}

Or in YAML:

# src/AppBundle/Resources/config/api_resources/resources.yml
resources:
    AppBundle\Entity\Product:
      properties:
        name:
          attributes:
            swagger_context:
              type: string
              enum: ['one', 'two']
              example: one
        timestamp:
          attributes:
            swagger_context:
              type: string
              format: date-time

Will produce the following Swagger documentation:

{
  "swagger": "2.0",
  "basePath": "/",

  "definitions": {
    "Product": {
      "type": "object",
      "description": "This is a product.",
      "properties": {
        "id": {
          "type": "integer",
          "readOnly": true
        },
        "name": {
          "type": "string",
          "description": "This is a name.",
          "enum": ["one", "two"],
          "example": "one"
        },
        "timestamp": {
          "type": "string",
          "format": "date-time"
        }
      }
    }
  }
}

Changing the Swagger UI Location

Sometimes you may want to have the API at one location, and the Swagger UI at a different location. This can be done by disabling the Swagger UI from the API Platform configuration file and manually adding the Swagger UI controller.

Disabling Swagger UI

# app/config/config.yml

api_platform:
    # ...
    enable_swagger_ui: false

Manually Registering the Swagger UI Controller

# app/config/routing.yml
swagger_ui:
    path: /docs
    controller: api_platform.swagger.action.ui

Change /docs to your desired URI you wish Swagger to be accessible on.

Enable Swagger doc for API Gateway

AWS API Gateway supports Swagger 2.0 partially, but it requires some changes. Fortunately, API Platform provides a way to be compatible with both Swagger 2.0 & API Gateway.

To enable API Gateway compatibility on your Swagger doc, add api_gateway=true query parameter:

http://www.example.com/docs.json?api_gateway=true

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