Skip to main content
Version: v3.x (DDN)

JSON:API Schema

Introduction​

Hasura DDN provides an OpenAPI 3.1 schema endpoint for the JSON:API interface, making it easier to explore, test, and integrate with your API. This schema gives you a complete overview of your API's structure, including available endpoints, models, and operations.

With the OpenAPI specification, you can generate interactive documentation using tools like Swagger UI or Redoc, making it simple to explore and understand your API. If you're building a client application, OpenAPI code generators can help you quickly scaffold client code. For testing, you can import the schema into Postman to validate requests and responses. Additionally, the schema enables automatic type generation for various programming languages, ensuring type safety in your applications.

By leveraging this schema, you can streamline API development, debugging, and integration, all while maintaining a standardized approach to working with JSON:API in Hasura DDN.

Schema endpoint​

To retrieve the OpenAPI specification for your JSON:API endpoints, send a GET request to:
GET /v1/rest/__schema

The response will be a standard OpenAPI 3.1 specification in JSON format, describing all available endpoints, models, and operations.

Authentication​

The schema endpoint follows the same authentication rules as your other API endpoints. Make sure to include appropriate authentication headers as configured in your authentication settings.

Response format​

The response is a JSON document conforming to the OpenAPI 3.1 specification. It includes:

  • API information and version
  • Available endpoints and operations
  • Model schemas and relationships
  • Request/response formats
Example response:
{
  "openapi": "3.1.0",
  "info": {
    "title": "Hasura JSONAPI (alpha)",
    "description": "REST API generated to match the JSON:API spec: https://jsonapi.org",
    "version": "0.1"
  },
  "paths": {
    // Available endpoints and operations
  },
  "components": {
    // Reusable components and schemas
  }
}

Integration examples​

Swagger UI​

To view your API documentation in Swagger UI:

  1. Visit Swagger Editor
  2. Copy your schema JSON from the /__schema endpoint
  3. Paste it into the editor

Postman​

To import your API into Postman:

  1. Copy the URL of your schema endpoint
  2. In Postman, click "Import" > "OpenAPI"
  3. Paste the URL or import the JSON directly

Learn more​

© 2025 Hasura Inc. All rights reserved