Generating APIs with REST Builder

Follow these steps to use REST Builder to create a headless REST API for your app:

  1. Create a project.

  2. Install REST Builder. For instructions on this, see REST Builder Gradle Plugin.

  3. Run gradlew clean deploy. Note that your Gradle wrapper may not be in your app’s project directory, so you may need to use .. to locate it (e.g., ../../../gradlew clean deploy).

  4. Create the *-api and *-impl projects with the usual files (build.gradle, bnd.bnd). Also create a rest-config.yaml with the author, paths, and packages. For example, here’s the rest-config.yaml for Liferay’s headless-delivery API:

    apiDir: "../headless-delivery-api/src/main/java"
    apiPackagePath: ""
        baseURI: "/headless-delivery"
        className: "HeadlessDeliveryApplication"
        name: "Liferay.Headless.Delivery"
    author: "Javier Gamarra"
    clientDir: "../headless-delivery-client/src/main/java"
    testDir: "../headless-delivery-test/src/testIntegration/java"
  5. In your *-impl module’s root folder, write your OpenAPI profile in YAML. You can use the Swagger Editor to validate syntax and ensure compliance with the OpenAPI specification.

  6. In your *-impl module folder, run gradlew buildREST (make sure you locate your Gradle wrapper as instructed in step two above).

  7. REST Builder generates the interfaces with the JAX-RS endpoints. It also generates a *ResourceImpl class where you must implement the business logic for each service.

  8. After implementing the business logic for each service, deploy your modules. Your APIs are then available at this URL:


    You can also execute jaxrs:check in the OSGi console to see all the JAX-RS endpoints.

REST Builder

Headless REST APIs

REST Builder Gradle Plugin

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