/*
* RHQ Management Platform
* Copyright (C) 2005-2008 Red Hat, Inc.
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation version 2 of the License.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
package org.rhq.plugins.agent;
import java.io.File;
import java.util.HashSet;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.mc4j.ems.connection.bean.attribute.EmsAttribute;
import org.rhq.core.domain.configuration.Configuration;
import org.rhq.core.domain.configuration.PropertySimple;
import org.rhq.core.pluginapi.inventory.DiscoveredResourceDetails;
import org.rhq.core.pluginapi.inventory.ResourceDiscoveryComponent;
import org.rhq.core.pluginapi.inventory.ResourceDiscoveryContext;
import org.rhq.core.system.OperatingSystemType;
import org.rhq.core.system.SystemInfo;
import org.rhq.enterprise.agent.Version;
/**
* This is the discovery component for the agent launcher script.
* This launcher script is for UNIX and is not to be found on a
* Windows platform. See {@link AgentJavaServiceWrapperDiscoveryComponent}
* for the analogous Windows component.
*
* @author John Mazzitelli
*/
public class AgentLauncherScriptDiscoveryComponent implements ResourceDiscoveryComponent<AgentServerComponent<?>> {
private final Log log = LogFactory.getLog(AgentLauncherScriptDiscoveryComponent.class);
/**
* The name of the plugin configuration simple property whose value is the launcher script file path.
* Package scoped so the component can use this.
*/
static final String PLUGINCONFIG_PATHNAME = "Pathname";
/**
* Simply returns the service resource.
*
* @see ResourceDiscoveryComponent#discoverResources(ResourceDiscoveryContext)
*/
public Set<DiscoveredResourceDetails> discoverResources(ResourceDiscoveryContext<AgentServerComponent<?>> context) {
log.info("Discovering RHQ Agent's launcher script service...");
HashSet<DiscoveredResourceDetails> set = new HashSet<DiscoveredResourceDetails>();
try {
String baseName = getBaseName(context.getSystemInformation());
if (baseName != null) {
EmsAttribute attrib = context.getParentResourceComponent().getAgentBean().getAttribute("Version");
attrib.refresh();
String version;
if (attrib.getValue() != null) {
version = attrib.getValue().toString();
} else {
version = Version.getProductVersion(); // just use the one we can get statically, its probably the correct version
}
// we know our agent plugin is running in the same process as our agent
// so the script must be on the same box that we are running on.
// try to find the file in one of several ways - but once we find it, stop (there is only ever one of them)
if (!findInAgentHome(context, version, baseName, set)) {
log.warn("Could not find the agent's launcher script anywhere");
}
}
} catch (Exception e) {
log.error("An error occurred while attempting to auto-discover the agent's launcher script", e);
}
return set;
}
/**
* Looks for the launcher script relative to the agent home directory.
*
* @param context
* @param version
* @param baseName
* @param discoveries where the new details are stored if the script is discovered
*
* @return <code>true</code> if this method discovers the launcher script; <code>false</code> if not
*/
private boolean findInAgentHome(ResourceDiscoveryContext<AgentServerComponent<?>> context, String version,
String baseName, HashSet<DiscoveredResourceDetails> discoveries) {
try {
EmsAttribute home = context.getParentResourceComponent().getAgentBean().getAttribute("AgentHomeDirectory");
home.refresh();
Object agentHome = home.getValue();
if (agentHome != null) {
File file = new File(agentHome.toString(), baseName);
if (file.exists()) {
discoveries.add(createDetails(context, version, file));
}
}
return discoveries.size() > 0;
} catch (Exception e) {
log.debug("Cannot use agent home to find launcher script. Cause: " + e);
return false;
}
}
private DiscoveredResourceDetails createDetails(ResourceDiscoveryContext<AgentServerComponent<?>> context,
String version, File discoveredLocation) {
String key = "launcherscript"; // this is a singleton resource; only ever one of these
String name = "RHQ Agent Launcher Script";
String description = "A script that can start the agent and manage its lifecycle as a service";
String location;
try {
location = discoveredLocation.getCanonicalPath(); // try to get the canonical path but...
} catch (Exception e) {
location = discoveredLocation.getAbsolutePath(); // ...if we can't, use absolute path
}
File launcher = new File(new File(location), "rhq-agent-wrapper.sh");
DiscoveredResourceDetails details = new DiscoveredResourceDetails(context.getResourceType(), key, name,
version, description, null, null);
Configuration pc = details.getPluginConfiguration();
pc.put(new PropertySimple(PLUGINCONFIG_PATHNAME, launcher.getAbsoluteFile()));
return details;
}
/**
* Returns the base filename where the launcher script is to be found.
* This is dependent on the platform we are running on.
* UNIX machines will return a non-<code>null</code> string but because the
* launcher script is not used by the agent on Windows machines, <code>null</code> will be returned
* when running on Windows machines.
*
* @param sysInfo used to determine what platform we are on
*
* @return the location of the launcher script that we are trying to discover, or <code>null</code> if we
* should not try to discovery the launcher script. The returned location is relative to agent home.
*/
private String getBaseName(SystemInfo sysInfo) {
String location = null;
try {
OperatingSystemType osType = sysInfo.getOperatingSystemType();
if (osType == OperatingSystemType.JAVA) {
String osName = System.getProperty("os.name", "").toLowerCase();
osType = osName.contains("windows") ? OperatingSystemType.WINDOWS : OperatingSystemType.LINUX;
}
if (osType != OperatingSystemType.WINDOWS) {
location = "bin";
}
} catch (Exception e) {
// can't determine os type, assume windows
}
return location;
}
}