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Web Service is one of many well-defined extension points supported by the WSO2 Governance Registry. Read more on Supported Extension Points for a complete list of extension points supported by WSO2 Governance Registry.

Project Object Model (POM) is an XML representation of a Maven project held in a file named pom.xml. You should find POM file by the name pom.xml inside GREG_HOME/ samples/handler/src.

<dependency>
    <groupId>org.wso2.carbon</groupId>
    <artifactId>org.wso2.carbon.governance.api</artifactId>
    <version>4.0.1</version>
</dependency>

<plugin>
    <groupId>org.apache.felix</groupId>
    <artifactId>maven-scr-plugin</artifactId>
</plugin>

<!--Fragment-Host>org.wso2.carbon.registry.core</Fragment-Host-->

The Fragment-Host Bundle Manifest Header declares this sample bundle to be a Fragment of the Registry Kernel. This would mean that the sample handler bundle will become an extension to the Registry Kernel. However, bundles containing services.xml files would not be deployed until the Apache Axis2 runtime has been initialized. Due to OSGi bundle start-up order, it is required that the Registry Kernel starts up before the Apache Axis2 runtime.

Since the Fragment now also being an extension to the Registry Kernel, the combination of this bundle and the Registry Kernel (plus any other fragments) should start up before the Apache Axis2 runtime. But, due to the bundle not getting deployed until the Apache Axis2 runtime has been initialized, it will create a deadlock situation. Due to this reason, we have to get rid of the Fragment-Host header.

<serviceGroup>
    <service name="EndpointLookupService" scope="transportsession">
        <transports>
            <transport>http</transport>
        </transports>
        <parameter name="ServiceClass" locked="false">
            org.wso2.carbon.registry.samples.services.EndpointLookupService
        </parameter>
    </service>
</serviceGroup>

package org.wso2.carbon.registry.samples.services;
 
import org.wso2.carbon.registry.core.service.RegistryService;
 
/**
 * @scr.component name="org.wso2.carbon.registry.samples.endpoint.lookup" immediate="true"
 * @scr.reference name="registry.service" interface="org.wso2.carbon.registry.core.service.RegistryService"
 * cardinality="1..1" policy="dynamic" bind="setRegistryService" unbind="unsetRegistryService"
 */
public class EndpointLookupServiceComponent {
 
    private static RegistryService registryService;
 
    protected void setRegistryService(RegistryService registryService) {
        EndpointLookupServiceComponent.registryService = registryService;
    }
 
    protected void unsetRegistryService(RegistryService registryService) {
        EndpointLookupServiceComponent.registryService = null;
    }
 
    public static RegistryService getRegistryService() {
        return registryService;
    }
}

package org.wso2.carbon.registry.samples.services;
 
import org.wso2.carbon.governance.api.exception.GovernanceException;
import org.wso2.carbon.governance.api.services.ServiceFilter;
import org.wso2.carbon.governance.api.services.ServiceManager;
import org.wso2.carbon.governance.api.services.dataobjects.Service;
import org.wso2.carbon.registry.core.Registry;
import org.wso2.carbon.registry.core.exceptions.RegistryException;
 
import java.util.LinkedList;
import java.util.List;
 
public class EndpointLookupService {
 
    private Registry governanceRegistry;
 
    public EndpointLookupService() {
        try {
            governanceRegistry = EndpointLookupServiceComponent.getRegistryService()
                    .getGovernanceSystemRegistry();
        } catch (RegistryException e) {
            e.printStackTrace();
        }
    }
 
    public String[] getEndpoints(final String serviceName, final String serviceNamespace,
                                 final String version, final String environment)
            throws GovernanceException {
        ServiceManager manager = new ServiceManager(governanceRegistry);
        Service[] services = manager.findServices(new ServiceFilter() {
            public boolean matches(Service service) throws GovernanceException {
                return serviceName.equals(service.getQName().getLocalPart()) &&
                        (serviceNamespace == null || serviceNamespace.length() == 0 ||
                                serviceNamespace.equals(service.getQName().getNamespaceURI())) &&
                        (version == null || version.length() == 0 ||
                                version.equals(service.getAttribute("overview_version")));
            }
        });
        if (services != null && services.length > 0) {
            List<String> endpoints = new LinkedList<String>();
            for (Service service : services) {
                String[] entries = service.getAttributes("endpoints_entry");
                if (entries != null && entries.length > 0) {
                    for (String entry : entries) {
                        int idx = entry.indexOf(":");
                        if (entry.substring(0, idx).equals(environment)) {
                            endpoints.add(entry.substring(idx + 1));
                        }
                    }
                }
            }
            return endpoints.toArray(new String[endpoints.size()]);
        }
        return new String[0];
    }
}

mvn clean install

The command mvn clean install will trigger an Apache Maven Build in your command line. This requires you having installed Apache Maven. See Installation Prerequisites for links on how to install it.

http://localhost:9763/services/EndpointLookupService/getEndpoints?serviceName=SimpleStockQuoteService&environment=Dev

In this step, we only have passed in the parameters serviceName and environment. This sample service also supports serviceNamespace and version as optional parameters.

<ns:getEndpointsResponse xmlns:ns="http://services.samples.registry.carbon.wso2.org"
                         xmlns:ax2549="http://exception.api.governance.carbon.wso2.org/xsd"
                         xmlns:ax2551="http://api.registry.carbon.wso2.org/xsd"
                         xmlns:ax2550="http://exceptions.core.registry.carbon.wso2.org/xsd">
    <ns:return>http://localhost:8280/SimpleStockQuoteService</ns:return>
    <ns:return>https://localhost:8243/SimpleStockQuoteService</ns:return>
</ns:getEndpointsResponse>

http://localhost:9763/services/EndpointLookupService?wsdl

http://localhost:9763/services/EndpointLookupService?wsdl

<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:ser="http://services.samples.registry.carbon.wso2.org">
   <soap:Header/>
   <soap:Body>
      <ser:getEndpoints>
         <ser:serviceName>SimpleStockQuoteService</ser:serviceName>
         <ser:environment>Dev</ser:environment>
      </ser:getEndpoints>
   </soap:Body>
</soap:Envelope>

Instructions on how to use the Governance API in Governance Registry to build in-VM services.