Integrating with an External WSO2 API Manager

This tutorial demonstrates how to integrate an external WSO2 API Manager (APIM) with WSO2 G-Reg. 

Introduction

WSO2 G-Reg implements Services (SOAP or REST) as configurable governance artifacts (RXT files), which you create using the G-Reg Publisher. Usually, you publish a service in WSO2 APIM using the APIM Publisher web interface. Instead, you can integrate WSO2 APIM with WSO2 G-Reg, to directly publish APIs to APIM Publisher using the services deployed in the WSO2 G-Reg. This guide explains how to configure the two products to expose services in the G-Reg as APIs in WSO2 APIM.

Prerequisites

Follow the steps below to set up the required prerequisites before starting the integration.

1. Download WSO2 Governance Registry (version 5.0.0 and above), and start the server. For instructions on running WSO2 G-Reg, see Running the Product. 

   Change the default port of WSO2 G-Reg (e.g. set a port offset of 1), to avoid port conflicts that may arise when running more than one WSO2 products on the same server. For instructions, see Changing the Default Ports with Offset.

2. Download WSO2 API Manager (version 1.9.x and above), and start the server.  For instructions on running WSO2 APIM, see Running the Product.

Configuring WSO2 G-Reg to publish services

Follow the steps below to configure WSO2 G-Reg to publish services on it to WSO2 APIM.

1.  Log in to the G-Reg Management Console using the following URL and admin/admin credentials:  https://10.100.5.72:9444/carbon

2. Click Extensions, and then click Lifecycles.
3. Click the corresponding View/Edit Link of the ServiceLifeCycle as shown below.
   

4. Replace the  <execution forEvent="Publish" class="org.wso2.carbon.governance.registry.extensions.executors.apistore.ApiStoreExecutor"> element in the configuration with a code block which defines an execution element in production state as shown in the example below. Add the API Manager credentials in it, so that it provides the API Manager's endpoint, username and password as executor parameters.

   Alternatively, you can do this change in the <GREG_HOME>/repository/resources/lifecycles/ServiceLifeCycle.xml file and then restart the G-Reg server.

   <execution forEvent="Publish" class="org.wso2.carbon.governance.registry.extensions.executors.apistore.ServiceToAPIExecutor">
      <parameter name="apim.endpoint" value="http://localhost:9763/"/>
      <parameter name="apim.username" value="admin"/>
      <parameter name="apim.password" value="admin"/>
      <parameter name="apim.env" value="dev"/>
      <parameter name="default.tier" value="Unlimited"/>
      <parameter name="throttlingTier" value="Unlimited,Unlimited,Unlimited,Unlimited,Unlimited"/>
   </execution>

   If you need to publish a REST service to WSO2 API Manager, replace the  <execution forEvent="Publish" class="org.wso2.carbon.governance.registry.extensions.executors.apistore.ApiStoreExecutor">  element in the  <GREG_HOME>/repository/resources/lifecycles/ServiceLifeCycle.xml  file with a code block which defines an  execution  element in  production  state as shown in the example below. Add the API Manager credentials in it, so that it provides the API Manager's endpoint, username and password as executor parameters.

   <execution forEvent="Publish" class="org.wso2.carbon.governance.registry.extensions.executors.apistore.RestServiceToAPIExecutor">
      <parameter name="apim.endpoint" value="http://localhost:9763/"/>
      <parameter name="apim.username" value="admin"/>
      <parameter name="apim.password" value="admin"/>
      <parameter name="apim.env" value="dev"/>
      <parameter name="default.tier" value="Unlimited"/>
      <parameter name="throttlingTier" value="Unlimited,Unlimited,Unlimited,Unlimited,Unlimited"/>
   </execution>

5. Click Save.

6. Click Yes in the message which pops up.

   

Setting up the service in WSO2 G-Reg

Follow the steps below to create/edit and publish the service, which you need to publish to WSO2 APIM.

1. Create the service, which you need to publish to WSO2 APIM in WSO2 G-Reg or edit it if it is an existing one. 

   When creating the service or editing an existing service, add the same values that you provided for the apim.endpoint parameter (e.g. http://localhost:9763/), and apim.env parameter (e.g. "dev") in the lifecycle executor in Integrating with an External WSO2 API Manager, for Environments and URL in the Endpoints tab as shown in the example below.  

   

2. Publish the  service you created or edited to WSO2 APIM Publisher. For instructions, see Managing Life Cycles of Assets.

Testing the API Published in WSO2 APIM 

Follow the steps below to test the API published in the WSO2 APIM by invoking it.

1. Log in to  the WSO2 APIM Publisher using the following URL and admin/admin credentials: https://10.100.5.72:9443/publisher. You view the service you published is successfully created as an API in the API Publisher as shown below.
   
2. Click on the API.
3. Click Edit as shown below.
   
   
4. Click Next: Implement > in the following screen.
   
5. Click Managed API as shown below.
   
6. Enter the preferred Production Endpoint, and click Next : Manage > as shown below.
   
   
7. Enter preferred details, and click Save & Publish as shown below.
   
8. Click Go to API Store in the message which pops up as shown below.
   
   
9. Select an Application, and click Subscribe as shown below.
   
   
10. Click Go To My Subscriptions in the message which pops up as shown below.
    

11. Click Generate keys button in the Keys - Production section as shown below. 

    You can skip this step if you already did it before.

    
    You view the generated keys as shown below.
    

12. Click on the API which you subscribed in the Subscribed APIs section at the end of the screen as shown below.
    
13. Click on the API Console tab, and click on the POST box, to expand it as shown below.
    
    
14. Click the Try it out! button. You view the result of invoking the API as shown in the below example.