/*
* JBoss, Home of Professional Open Source.
* Copyright 2010, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.domain.controller.plan;
import static org.jboss.as.controller.descriptions.ModelDescriptionConstants.FAILURE_DESCRIPTION;
import java.util.Set;
import org.jboss.as.domain.controller.logging.DomainControllerLogger;
import org.jboss.as.domain.controller.ServerIdentity;
import org.jboss.dmr.ModelNode;
/**
* Policy used to determine whether a server can be updated, based on the result
* of updates made to other servers.
*
* @author Brian Stansberry
*/
class ServerUpdatePolicy {
private final ConcurrentGroupServerUpdatePolicy parent;
private final String serverGroupName;
private final Set<ServerIdentity> servers;
private int successCount;
private int failureCount;
private final int maxFailed;
/**
* Constructor for normal case where the max number of failures before
* plan is considered failed comes from the plan.
*
* @param parent parent policy
* @param serverGroupName the name of the server group being updated
* @param servers servers that are being updated
* @param maxFailures maximum number of failed servers before the server group should be rolled back
*/
ServerUpdatePolicy(final ConcurrentGroupServerUpdatePolicy parent,
final String serverGroupName,
final Set<ServerIdentity> servers,
final int maxFailures) {
assert parent != null : "parent is null";
assert serverGroupName != null : "serverGroupName is null";
assert servers != null : "servers is null";
this.parent = parent;
this.serverGroupName = serverGroupName;
this.servers = servers;
this.maxFailed = maxFailures;
}
/**
* Constructor for the rollback case where failure on one server should
* not prevent execution on the others.
*
* @param parent parent policy
* @param serverGroupName the name of the server group being updated
* @param servers servers that are being updated
*/
ServerUpdatePolicy(final ConcurrentGroupServerUpdatePolicy parent,
final String serverGroupName,
final Set<ServerIdentity> servers) {
assert parent != null : "parent is null";
assert serverGroupName != null : "serverGroupName is null";
assert servers != null : "servers is null";
this.parent = parent;
this.serverGroupName = serverGroupName;
this.servers = servers;
this.maxFailed = servers.size();
}
/**
* Gets the name of the server group to which this policy is scoped.
*
* @return the name of the server group. Will not be <code>null</code>
*/
public String getServerGroupName() {
return serverGroupName;
}
/**
* Gets whether the given server can be updated.
*
* @param server the id of the server. Cannot be <code>null</code>
*
* @return <code>true</code> if the server can be updated; <code>false</code>
* if the update should be cancelled
*
* @throws IllegalStateException if this policy is not expecting a request
* to update the given server
*/
public boolean canUpdateServer(ServerIdentity server) {
if (!serverGroupName.equals(server.getServerGroupName()) || !servers.contains(server)) {
throw DomainControllerLogger.HOST_CONTROLLER_LOGGER.unknownServer(server);
}
if (!parent.canChildProceed())
return false;
synchronized (this) {
return failureCount <= maxFailed;
}
}
/**
* Records the result of updating a server.
*
* @param server the id of the server. Cannot be <code>null</code>
* @param response the result of the updates
*/
public void recordServerResult(ServerIdentity server, ModelNode response) {
if (!serverGroupName.equals(server.getServerGroupName()) || !servers.contains(server)) {
throw DomainControllerLogger.HOST_CONTROLLER_LOGGER.unknownServer(server);
}
boolean serverFailed = response.has(FAILURE_DESCRIPTION);
DomainControllerLogger.HOST_CONTROLLER_LOGGER.tracef("Recording server result for '%s': failed = %s",
server, server);
synchronized (this) {
int previousFailed = failureCount;
if (serverFailed) {
failureCount++;
}
else {
successCount++;
}
if (previousFailed <= maxFailed) {
if (!serverFailed && (successCount + failureCount) == servers.size()) {
// All results are in; notify parent of success
parent.recordServerGroupResult(serverGroupName, false);
}
else if (serverFailed && failureCount > maxFailed) {
parent.recordServerGroupResult(serverGroupName, true);
}
}
}
}
/**
* Gets whether the
* {@link #recordServerResult(org.jboss.as.domain.controller.ServerIdentity, org.jboss.dmr.ModelNode)} recorded results}
* constitute a failed server group update per this policy.
*
* @return <code>true</code> if the server group update is considered to be a failure;
* <code>false</code> otherwise
*/
public synchronized boolean isFailed() {
// Here we use successCount instead of failed count, so
// non-recorded servers are treated as failures
return (servers.size() - successCount) > maxFailed;
}
}