dosgi/src/main/java/org/apache/karaf/cellar/dosgi/shell/ListDistributedServicesCommand.java

/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.karaf.cellar.dosgi.shell;

import org.apache.karaf.cellar.core.Node;
import org.apache.karaf.cellar.core.shell.CellarCommandSupport;
import org.apache.karaf.cellar.dosgi.Constants;
import org.apache.karaf.cellar.dosgi.EndpointDescription;
import org.apache.karaf.shell.commands.Command;
import org.apache.karaf.shell.table.ShellTable;

import java.util.Map;
import java.util.Set;

@Command(scope = "cluster", name = "service-list", description = "List the services available on the cluster")
public class ListDistributedServicesCommand extends CellarCommandSupport {

    @Override
    protected Object doExecute() throws Exception {
        ClassLoader originalClassLoader = Thread.currentThread().getContextClassLoader();
        try {
            Thread.currentThread().setContextClassLoader(getClass().getClassLoader());
            Map<String, EndpointDescription> remoteEndpoints = clusterManager.getMap(Constants.REMOTE_ENDPOINTS);
            if (remoteEndpoints != null && !remoteEndpoints.isEmpty()) {
                ShellTable table = new ShellTable();
                table.column("Service Class");
                table.column("Provider Node");
                for (Map.Entry<String, EndpointDescription> entry : remoteEndpoints.entrySet()) {
                    EndpointDescription endpointDescription = entry.getValue();
                    String serviceClass = endpointDescription.getServiceClass();
                    Set<Node> nodes = endpointDescription.getNodes();
                    for (Node node : nodes) {
                        table.addRow().addContent(serviceClass, node.getId());
                        serviceClass = "";
                    }
                }
                table.print(System.out);
            } else {
                System.out.println("No service available on the cluster");
            }
        } finally {
            Thread.currentThread().setContextClassLoader(originalClassLoader);
        }
        return null;
    }

}