Swagger Core RESTEasy 2.X Project Setup 1.5

Ron edited this page Jun 8, 2015 · 5 revisions

This page contains the required information to add Swagger to your RESTEasy 2.X application.

You can find additional information at our main set up page.

NOTE: swagger-core 1.5.X produces Swagger 2.0 definition files. For more information, check out the swagger-spec repository.

You need to complete the three steps in order to set up your application with Swagger:

  1. Adding the dependencies to your application
  2. Hooking up Swagger-Core in your Application
  3. Configure and Initialize Swagger

Once you complete these steps, your Swagger definition would be available at /swagger.json and /swagger.yaml at the context root of your application.



As part of the 1.5 release, we've repackaged the project under the io.swagger package. If you're migrating, you need to update your imports accordingly. This will mostly affect your annotation usage. A simple find/replace should cover this change easily.

The groupId in maven has also changed to io.swagger.


For your convenience there are two RESTEasy sample projects:

  1. java-resteasy - includes a configuration based on the usage of the Application class.
  2. java-resteasy-spring - uses RESTEasy's own method of integrating with Spring.


1. Adding the dependencies to your application

Check the change log to see information about the latest version and the changes from previous versions.

Use the following maven dependency:

<dependency>
  <groupId>io.swagger</groupId>
  <artifactId>swagger-jaxrs</artifactId>
  <version>1.5.0</version>
</dependency>


2. Hooking up Swagger-Core in your Application

RestEasy offers several mechanisms to register resources and providers. Use one of the following to hook up swagger-core, based on the method you already use:

You can use the options mentioned using any form of available web.xml RestEasy initialization (servlets, filter or listener).

Regardless of the configuration method, the Swagger specification will be available at /swagger.json under the designated context root. If, for example, you mapped RestEasy to serve requests under /myapi/*, then Swagger will be available under /myapi/swagger.json.


Manual registration using configuration switches

Using RestEasy's <context-param> switches, you can set your applications resources manually. The following <context-param> need to be part of your web.xml:

<context-param>
    <param-name>resteasy.providers</param-name>
    <param-value>
      io.swagger.jaxrs.listing.ApiListingResource,
      io.swagger.jaxrs.listing.SwaggerSerializers,
      {your.application.providers}
    </param-value>
  </context-param>

Note: {your.application.providers} is your application's list of comma separated providers acting as resources.

You can now proceed to the next section - Configure and Initialize Swagger.


Automatic scanning and registration

If you've already configured the following <context-param>:

  <context-param>
    <param-name>resteasy.scan</param-name>
    <param-value>true</param-value>
  </context-param>

that will also pick Swagger's resources and providers automatically.

Note that if you only set resteasy.scan.providers or resteasy.scan.resources to true, you will have to either enable the other as well or configure the relevant resource/providers as suggested in the previous configuration option.

When using automatic scanning, swagger-core is unable to detect the resources automatically. To resolve that, you must tell swagger-core which packages to scan. The suggested solution is to use the BeanConfig method (most likely as a Servlet). Make sure to use the setResourcePackage(String) method in order to tell Swagger where it can find the resources.

You can now proceed to the next section - Configure and Initialize Swagger.


Using a custom Application subclass

When using a custom Application subclass, you would need to add swagger-core's providers to the set up process. For example:

public class SampleApplication extends Application {
    @Override
    public Set<Class<?>> getClasses() {
        Set<Class<?>> resources = new HashSet();

        //resources.add(FirstResource.class);
        //resources.add(SecondResource.class);
        //...

        resources.add(io.swagger.jaxrs.listing.ApiListingResource.class);
        resources.add(io.swagger.jaxrs.listing.SwaggerSerializers.class);

        return resources;
    }
}

The commented part is where you'd add your own application's resources and providers.

You can now proceed to the next section - Configure and Initialize Swagger.


Using Spring

The following instruction are based on using RESTEasy's own listener for Spring integration (the org.jboss.resteasy.plugins.spring.SpringContextLoaderListener listener).

Swagger Core's classes are framework-agnostic and as such do contain Spring annotations and will not be picked by Spring's scanning feature.

As such, you need to add Swagger-Core's relevant classes manually to your application context configuration file:

    <bean id="apiListingResourceJSON" class="io.swagger.jaxrs.listing.ApiListingResource"/>
    <bean id="apiDeclarationProvider" class="io.swagger.jaxrs.listing.SwaggerSerializers"/>

When using Spring, you must add a BeanConfig bean to initialize Swagger.

You can now proceed to the next section - Configure and Initialize Swagger.



3. Configure and Initialize Swagger

There are two main ways to configure and initialize the Swagger definition within your application. The first, within the web.xml, offers a simplified method of configuration. If you're looking for more control, then the BeanConfig path is the one you should choose.


Using Swagger's Servlet in the web.xml

Swagger offers a simple Servlet that can be used to initialize it.

Add the following snippet to your web.xml:

    <servlet>
        <servlet-name>Jersey2Config</servlet-name>
        <servlet-class>io.swagger.jaxrs.config.DefaultJaxrsConfig</servlet-class>
        <init-param>
            <param-name>api.version</param-name>
            <param-value>1.0.0</param-value>
        </init-param>
        <init-param>
            <param-name>swagger.api.basepath</param-name>
            <param-value>http://localhost:8080/api</param-value>
        </init-param>
        <load-on-startup>2</load-on-startup>
    </servlet>

A few things to note:

  1. The api.version should reflect the version of your own API.
  2. swagger.api.basepath should point to the context root of your API. This defers from server to server and how you configured your JAX-RS application.
  3. There's no <servlet-mapping> for this servlet as it is only used for initialization and doesn't actually expose any interface.

You are done with this guide! You should now be able to access the Swagger definition at /swagger.json and /swagger.yaml at the context root of your application.


Using Swagger's BeanConfig

Swagger's BeanConfig class allows you to set various properties for Swagger's initialization.

Method Property Name Purpose
setTitle(String) title Sets the title of the application.
setDescription(String) description Sets the description of the application.
setTermsOfServiceUrl(String) termsOfServiceUrl Sets the URL of the application's Terms of Service.
setContact(String) contact Sets the contact information for the application.
setLicense(String) license Sets the license of the application.
setLicenseUrl(String) licenseUrl Sets the licesne url of the application.
setVersion(String) version Sets the version of the API.
setSchemes(String[]) schemes Sets the schemes for the API URLs (http, https).
setHost(String) host Sets the host (including a port) for the API URLs. Does not include the schemes nor context root.
setBasePath(String) basePath Sets the context root for the API calls.
setFilterClass(Sting) filterClass Sets a security filter for Swagger's documentation.
setResourcePackage(String) resourcePackage Sets which package(s) Swagger should scan to pick up resources. If there's more than one package, it can be a list of comma-separated packages.
setScan(boolean) scan When set to true, Swagger will build the documentation.
setPrettyPrint(boolean) prettyPrint Sets whether the swagger.json will be pretty printed.

In order for the Swagger to operate properly, you must set the base path of the application.

In order for Swagger to actually produce the documentation, you must setScan(true).

The BeanConfig should be called when your application starts up. The two common use cases are either using a Servlet or the Application class if you're already using one. Otherwise, any other method you use at your application's initialization could work.

Using a Servlet

A sample servlet would be:

package io.swagger.api.util;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;

public class Bootstrap extends HttpServlet {
    @Override
    public void init(ServletConfig config) throws ServletException {
        super.init(config);

        BeanConfig beanConfig = new BeanConfig();
        beanConfig.setVersion("1.0.2");
        beanConfig.setSchemes(new String[]{"http"});
        beanConfig.setHost("localhost:8002");
        beanConfig.setBasePath("/api");
        beanConfig.setResourcePackage("io.swagger.resources");
        beanConfig.setScan(true);
    }
}

And adding the following snippet to the web.xml will ensure the initialization of Swagger:

    <servlet>
        <servlet-name>SwaggerBootstrap</servlet-name>
        <servlet-class>io.swagger.api.util.Bootstrap</servlet-class>
        <load-on-startup>2</load-on-startup>
    </servlet>

There's no need for a URL mapping for this servlet as it is only used to initialize the application.

You are done with this guide! You should now be able to access the Swagger definition at /swagger.json and /swagger.yaml at the context root of your application.


Using the Application class

If you're already using an Application class to configure your JAX-RS application, you can use its constructor to set up Swagger:

public class SampleApplication extends Application {

    public SampleApplication() {
        BeanConfig beanConfig = new BeanConfig();
        beanConfig.setVersion("1.0.2");
        beanConfig.setSchemes(new String[]{"http"});
        beanConfig.setHost("localhost:8002");
        beanConfig.setBasePath("/api");
        beanConfig.setResourcePackage("io.swagger.resources");
        beanConfig.setScan(true);
    }

    @Override
    public Set<Class<?>> getClasses() {
        // set your resources here
    }
}

You are done with this guide! You should now be able to access the Swagger definition at /swagger.json and /swagger.yaml at the context root of your application.


Using Spring's Bean Declaration

When using Spring, you must include a BeanConfig bean declaration in your application context configuration file. When using Spring, Swagger-Core cannot pick up the resources automatically, so must set the value of the resourcePackage property to which packages need to be scanned by Swagger. You must also set the scan property to be true for the scanning to take place.

A sample declaration would be:

    <bean id="beanConfig" class="io.swagger.jaxrs.config.BeanConfig">
        <property name="title" value="Swagger Sample App"/>
        <property name="version" value="1.0.0" />
        <property name="schemes" value="http" />
        <property name="host" value="localhost:8002" />
        <property name="basePath" value="/api"/>
        <property name="resourcePackage" value="io.swagger.resources"/>
        <property name="scan" value="true"/>
    </bean>

You can use any of the properties available with to the BeanConfig to customize your Swagger configuration.

You are done with this guide! You should now be able to access the Swagger definition at /swagger.json and /swagger.yaml at the context root of your application.