shell/src/main/java/org/apache/karaf/cellar/shell/handler/HandlersSupport.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.shell.handler;

import org.apache.karaf.cellar.core.Node;
import org.apache.karaf.cellar.core.control.ManageHandlersCommand;
import org.apache.karaf.cellar.core.control.ManageHandlersResult;
import org.apache.karaf.cellar.shell.ClusterCommandSupport;
import org.apache.karaf.shell.support.table.ShellTable;

import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * Generic cluster event handler shell command support.
 */
public abstract class HandlersSupport extends ClusterCommandSupport {

    protected Object doExecute(String handlerName, List<String> nodeIdsOrAliases, Boolean status) throws Exception {

        ManageHandlersCommand command = new ManageHandlersCommand(clusterManager.generateId());
        command.setTimeout(timeout * 1000);

        // looking for nodes and check if exist
        Set<Node> recipientList = new HashSet<Node>();
        if (nodeIdsOrAliases != null && !nodeIdsOrAliases.isEmpty()) {
            for (String nodeIdOrAlias : nodeIdsOrAliases) {
                Node node = clusterManager.findNodeByIdOrAlias(nodeIdOrAlias);
                if (node == null) {
                    System.err.println("Cluster node " + nodeIdOrAlias + " doesn't exist");
                } else {
                    recipientList.add(node);
                }
            }
        } else {
            if (status == null) {
                // in case of status display, select all nodes
                recipientList = clusterManager.listNodes();
            } else {
                // in case of status change, select only the local node
                recipientList.add(clusterManager.getNode());
            }
        }

        if (recipientList.size() < 1) {
            return null;
        }

        command.setDestination(recipientList);
        command.setHandlerName(handlerName);
        command.setStatus(status);

        Map<Node, ManageHandlersResult> results = executionContext.execute(command);
        if (results == null || results.isEmpty()) {
            System.out.println("No result received within given timeout");
        } else {
            ShellTable table = new ShellTable();
            table.column(" ");
            table.column("Node");
            table.column("Status");
            table.column("Event Handler");
            for (Map.Entry<Node,ManageHandlersResult> handlersResultEntry : results.entrySet()) {
                Node node = handlersResultEntry.getKey();
                String local = "";
                if (node.equals(clusterManager.getNode())) {
                    local = "x";
                }
                ManageHandlersResult result = handlersResultEntry.getValue();
                if (result != null && result.getHandlers() != null) {

                    for (Map.Entry<String,String>  handlerEntry: result.getHandlers().entrySet()) {
                        String handler =  handlerEntry.getKey();
                        String s = handlerEntry.getValue();
                        table.addRow().addContent(local, node.getId(), s, handler);
                    }
                }
            }
            table.print(System.out);
        }
        return null;
    }

}