/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
/*
* NodeAgentProxy.java
*
* Created on September 15, 2003, 1:37 PM
*/
package com.sun.enterprise.ee.admin.proxy;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.lang.reflect.InvocationHandler;
import java.io.IOException;
import java.util.HashMap;
import java.util.logging.Logger;
import java.util.logging.Level;
import java.net.ConnectException;
import com.sun.enterprise.admin.servermgmt.InstanceException;
import com.sun.enterprise.ee.admin.servermgmt.AgentException;
import com.sun.logging.ee.EELogDomains;
import javax.management.MBeanServerConnection;
import javax.management.ObjectName;
import javax.management.MalformedObjectNameException;
import javax.management.MBeanException;
import com.sun.enterprise.ee.admin.clientreg.NodeAgentRegistry;
import com.sun.enterprise.ee.admin.proxy.BaseProxy;
import com.sun.enterprise.config.ConfigContext;
import com.sun.enterprise.config.serverbeans.ServerBeansFactory;
import com.sun.enterprise.config.serverbeans.Domain;
import com.sun.enterprise.config.serverbeans.NodeAgents;
import com.sun.enterprise.config.serverbeans.NodeAgent;
import com.sun.enterprise.config.serverbeans.ElementProperty;
import com.sun.enterprise.config.ConfigException;
import com.sun.enterprise.config.ConfigContext;
import com.sun.enterprise.config.ConfigException;
import com.sun.enterprise.server.ApplicationServer;
import com.sun.enterprise.server.ServerContextImpl;
import com.sun.enterprise.admin.server.core.AdminService;
import com.sun.enterprise.admin.util.IAdminConstants;
import com.sun.enterprise.admin.configbeans.BaseConfigBean;
import com.sun.enterprise.util.i18n.StringManager;
import com.sun.enterprise.ee.admin.mbeanapi.NodeAgentMBean;
/**
* @author kebbs
*
* The NodeAgentProxy class is a dynamic proxy used to invoke methods on a Node Agent. In
* addition to invoking the remote MBean server in the Node Agent, the proxy
* performs two tasks:
*
* 1) Attempts to rendezvous with the Node Agent if this has not already happened. This
* "rendezvous on demand" functionality is necessary since it is not clear when the node
* agent will be running. The common case here is that the node agent is not installed or
* is not bound to a DAS. Then the node agent is bound (bind-nodeagent) and instances
* are created (create-instance). Then the node agent is installed still in an unbound
* state not knowing the DAS properties. The operation targeted at the node agent (e.g.
* create-instance) will trigger an rendezvous automatically.
*
* 2) Because the Node Agent is down, some of its operations are not required to
* succeed. For example start/stop-instance must be able to reach the Node Agent
* since there is no persistent state in domain.xml associated with these operations;
* however, addition of new server instances persists state in domain.xml. If the
* node agent is unreachable during these operations, then this is not considered
* a failure since the node agent will pick up the changes the next time it is restarted
* and resynchronizes.
*/
public class NodeAgentProxy extends BaseProxy implements InvocationHandler {
/**
* Class InvocationAttributes stores information about each method invoked in the
* dynamic proxy.
*/
private class InvocationAttributes {
boolean _mustSucceed;
InvocationAttributes(boolean mustSucceed) {
_mustSucceed = mustSucceed;
}
boolean mustSucceed() {
return _mustSucceed;
}
}
private static final StringManager _strMgr =
StringManager.getManager(NodeAgentProxy.class);
private static Logger _logger = null;
//The _invocationAttributes maps a methodName to an InvocationAttributes object.
private static HashMap _invocationAttributes = null;
//Default invocationAttributes
private static InvocationAttributes _defaultAttributes = null;
//The default domain name for the Node Agent's mbean server.
private static String _defaultDomain = null;
//FIXME: Should'nt the object name for the node agent have its name embedded in it
//rather than making its host and port be the only differentiating factory. If so
//this should not be static.
private ObjectName _objectName = null;
private MBeanServerConnection _connection = null;
private String _nodeAgentName = null;
/**
* Returns a dynamic proxy capable of implementing the NodeAgentMBean interface.
*/
public static NodeAgentMBean getNodeAgentProxy(String nodeAgentName)
{
return (NodeAgentMBean)Proxy.newProxyInstance(
NodeAgentMBean.class.getClassLoader(),
new Class[] {NodeAgentMBean.class}, new NodeAgentProxy(nodeAgentName));
}
private String getNodeAgentName() {
return _nodeAgentName;
}
private static Logger getLogger()
{
if (_logger == null) {
_logger = Logger.getLogger(EELogDomains.EE_ADMIN_LOGGER);
}
return _logger;
}
/**
* Creates a new instance of NodeAgentProxy. We initialize our static content
* only once.
*/
private NodeAgentProxy(String nodeAgentName) {
_nodeAgentName = nodeAgentName;
synchronized (NodeAgentProxy.class) {
if (_invocationAttributes == null) {
_invocationAttributes = new HashMap();
_invocationAttributes.put("synchronizeWithDAS",
new InvocationAttributes(false));
//_invocationAttributes.put("rendezvousWithNodeAgent",
// new InvocationAttributes(false));
}
}
}
private InvocationAttributes getInvocationAttributes(String methodName)
{
InvocationAttributes attrs = (InvocationAttributes)_invocationAttributes.get(methodName);
//If the attributes are not found, revert to the default.
if (attrs == null) {
if (_defaultAttributes == null) {
_defaultAttributes = new InvocationAttributes(true);
}
attrs = _defaultAttributes;
}
return attrs;
}
/**
* Returns the object name for the specified node agent. Really the object name
* seems to be the same across all node agents.
*/
private ObjectName getObjectName() throws IOException,
MalformedObjectNameException, AgentException
{
if (_objectName == null) {
if (_defaultDomain == null) {
_defaultDomain = getConnection().getDefaultDomain();
}
_objectName = new ObjectName(_defaultDomain + ":type=NodeAgent,name=" +
getNodeAgentName() + ",category=config");
}
return _objectName;
}
/**
* Get a connection to the node agent's mbean server using the NodeAgentRegistry
*/
private MBeanServerConnection getConnection() throws AgentException {
if (_connection == null) {
_connection = NodeAgentRegistry.getNodeAgentConnection(getNodeAgentName());
}
return _connection;
}
/**
* hasRendezvousOccurred - this method report whether the nodeagent has rendezvoused with the DAS
* @return - true means the nodeagent has rendezvoused and the mbean invoke can proceed
* false means that the nodeagent has not redezvoused and the mbean invoke can not proceed
*/
private boolean hasRendezvousOccurred() throws ConfigException, MBeanException
{
final ConfigContext configContext =
ApplicationServer.getServerContext().getConfigContext();
final Domain domain = ServerBeansFactory.getDomainBean(configContext);
final NodeAgents controllers = domain.getNodeAgents();
final NodeAgent controller = controllers.getNodeAgentByName(getNodeAgentName());
boolean rendezvousOccurred = true;
ElementProperty rendezvousProperty = null;
//It is an expected case for the controller to be null. In the case where we
//are unbinding from a node agent, the node controller element will already be
//removed before invoking synchronizeWithDAS via this proxy.
//Tested case where nodeagent has never rendezvoused and then it is deleted, works correctly
//with connection failure exception being thrown
if (controller != null) {
//See if a rendezvous has occurred
rendezvousProperty = controller.getElementPropertyByName(
IAdminConstants.RENDEZVOUS_PROPERTY_NAME);
rendezvousOccurred = new Boolean(rendezvousProperty.getValue()).booleanValue();
}
if (rendezvousOccurred) {
if (controller == null) {
getLogger().log(Level.FINEST, "NodeAgentProxy: Defaulted to NodeAgent has rendezvoused since the agent has been removed ???");
} else {
getLogger().log(Level.FINEST, "NodeAgentProxy: The Nodeagent has rendezvoused with the DAS");
}
} else {
getLogger().log(Level.FINEST, "NodeAgentProxy: The NodeAgent has not rendezvoused with the DAS");
}
return rendezvousOccurred;
}
private Exception mangleInvokeException(Exception ex) {
Exception result = null;
//MBeanException and AgentException can pass through directly. All other exceptions must
//be wrapped as an agent exception. This is to avoid a UndeclaredException from being thrown
//from the dynamic proxies invoke method. In other words MBeanException and AgentException
//are the only exceptions being thrown from the NodeAgentMBean interface.
//The MBeanException is a little tricky, we need to propagate its cause rather than
//the exception itself. This is necessary to preserve the original message of the exception
//so that the CLI can display it.
if (ex instanceof MBeanException) {
Throwable t = ex.getCause();
if (t != null) {
if (t instanceof Exception) {
ex = (Exception)t;
}
}
result = ex;
}
if (ex instanceof AgentException) {
result = ex;
} else {
result = new AgentException(ex);
}
//If the server is unreachable then we want to mark the connection as disabled
if (isUnreachable(ex)) {
try {
NodeAgentRegistry.disconnectNodeAgentConnection(getNodeAgentName());
} catch (Exception ex2) {
getLogger().log(Level.WARNING, "nodeAgent.proxy.exception", ex2);
}
}
return result;
}
/**
* Invoke a method on the dynamic proxy. This methos will throw a ConnectException
* if the NodeAgent has yet to rendezvous with DAS. This exception will thrown only if
* the command is flagged a "mustSuceed", if not, it will be logged at the "FINE" log level.
*/
public Object invoke(Object proxy, Method method, Object[] args)
throws Throwable
{
final String methodName = method.getName();
getLogger().log(Level.FINEST, "NodeAgentProxy:invoke " + methodName);
InvocationAttributes attrs = getInvocationAttributes(methodName);
Exception exception = null;
Object result = null;
try {
// check to see if nodeagent has rendezvoused with DAS
// if not, can't continue with any of the nodeagent commands
if(!hasRendezvousOccurred()) {
// throw a ConnectException so the isReachable method
// works correctly
throw new ConnectException(_strMgr.getString("nodeAgent.not.rendezvoused"));
}
getLogger().log(Level.FINEST, "Sending command ....");
result = getConnection().invoke(getObjectName(), methodName,
args, getParameterTypes(method.getParameterTypes()));
return result;
} catch (Exception ex) {
getLogger().log(Level.FINEST, "NodeAgentProxy:invoke: Connection processing exception: " + ex.toString());
exception = mangleInvokeException(ex);
if (attrs.mustSucceed()) {
throw exception;
} else {
//Do not log exceptions indicating that the node agent was unreachable (i.e. down)
if (!isUnreachable(exception)) {
getLogger().log(Level.FINE, "nodeAgent.proxy.exception", exception);
} else {
getLogger().log(Level.FINE, "nodeAgent.proxy.cannotConnect", getNodeAgentName());
}
return result;
}
}
}
}