server/client/AlerterSkeleton.java

/* 
 * i-scream central monitoring system
 * http://www.i-scream.org
 * Copyright (C) 2000-2002 i-scream
 * 
 * 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; either version 2
 * of the License, or (at your option) any later version.
 * 
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

//---PACKAGE DECLARATION---
package uk.org.iscream.cms.server.client;

//---IMPORTS---
import uk.org.iscream.cms.server.client.*;
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.util.*;
import uk.org.iscream.cms.server.componentmanager.*;
import java.text.*;
import java.util.Date;
import java.util.Locale;

/**
 * Skeleton class for Alerters
 * This skeleton reads alerts from the alert queue designated 
 * to the Alerter, it then feeds the alerts to the sendAlert
 * method, which the extending class should implement.  The class
 * should then handle sending the message.  This class also has a 
 * method to allow formatting of messages.
 *
 * @author  $Author: tdb $
 * @version $Id: AlerterSkeleton.java,v 1.13 2004/08/01 10:40:40 tdb Exp $
 */
public abstract class AlerterSkeleton extends Thread implements PluginAlerter {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.13 $";

    /**
     * The default level to send alerts at
     */
    public final String DEFAULT_LEVEL = Alert.alertLevels[0];
    
    /**
     * If a configuration property is not 
     * configured, this will be used instead.
     */
    public final String NOT_CONFIGURED = "<NOT CONFIGURED>";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Constructs and starts the alerter reading alerts
     */
    public AlerterSkeleton() {
        _logger.write(toString(), Logger.SYSINIT, "started.");
        this.start();
    }

//---PUBLIC METHODS---

    /**
     * Reads the next alert from the alerter queue for this
     * alerter.  It then looks up Alerter.<alerter name>.level in
     * the configuration to determine the lowest level of alert
     * the extending alerter should send.  If the alert is
     * above this level, or if the alert is an OK for an alert
     * escalation which did rise above this alerters level, it then
     * calls sendAlert to tell the alerter to send the alert.  If it
     * isn't above this level, it ignores the alert.
     */
    public void run() {
        while(_running) {
            try {
                Alert alert = (Alert) getQueue().get(getQueueId());
                String levelName;
                try {
                    levelName = _cp.getProperty(_name, "Alerter." + getFName() + ".level");
                } catch (PropertyNotFoundException e) {
                    levelName = DEFAULT_LEVEL;
                    _logger.write(toString(), Logger.WARNING, "Alerter." + getFName() + ".level value unavailable using default of " + levelName);
                }
                int level = StringUtils.getStringPos(levelName, Alert.alertLevels);
                // only send if it's equal (or above) our level
                if(((alert.getLevel() == 0) && (alert.getLastLevel() >= level)) || (alert.getLevel() >= level)) {
                    sendAlert(alert);
                }
            } catch (InvalidQueueException e) {
                _logger.write(this.toString(), Logger.ERROR, "Unable to get queue.");
            }
        }
    }
    
    /**
     * Sends an alert object using whatever transport
     * mechanism the extending class is implementing.
     *
     * @param alert the Alert to send
     */
    protected abstract void sendAlert(Alert alert);
    
    /**
     * Processes a message, replace key fields (eg. %level%) with
     * representative text from the given Alert object.
     *
     * @param message The message to process
     * @param alert The Alert object to get data from
     * @return the processed message
     */
    protected String processAlertMessage(String message, Alert alert) {
        // get some values
        String alertType = Alert.alertLevels[alert.getLevel()];
        String thresholdType = Alert.thresholdLevels[alert.getThreshold()];
        String timeSinceFirst = DateUtils.formatTime((System.currentTimeMillis() - alert.getInitialAlertTime())/1000, "%DAYS% days, %HOURS% hours, %MINS% mins, and %SECS% secs");
        String timeFirstOccured = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, Locale.UK).format(new Date(alert.getInitialAlertTime()));
        
        // replace fields in message
        message = StringUtils.replaceText(message, "%level%", alertType);
        message = StringUtils.replaceText(message, "%threshold%", thresholdType);
        message = StringUtils.replaceText(message, "%source%", alert.getSource());
        message = StringUtils.replaceText(message, "%value%", alert.getValue());
        message = StringUtils.replaceText(message, "%thresholdValue%", alert.getThresholdValue());
        message = StringUtils.replaceText(message, "%attributeName%", alert.getAttributeName());
        message = StringUtils.replaceText(message, "%timeTillNextAlert%",  DateUtils.getTimeString(Long.parseLong(alert.getTimeTillNextAlert())));
        message = StringUtils.replaceText(message, "%timeSinceFirstAlert%", timeSinceFirst);
        message = StringUtils.replaceText(message, "%timeOfFirstAlert%", timeFirstOccured);
        return message;
    }
    
    /**
     * Return the String representation of what the alerter does
     *
     * @return the description
     */
    public abstract String getDescription();


//---PRIVATE METHODS---

//---ACCESSOR/MUTATOR METHODS---
    
    /**
     * Gets hold of the Alerts queue from the AlerterManager.
     *
     * @return The Alerts queue
     */
    protected Queue getQueue() {
        return AlerterManager.getInstance().getQueue();
    }
    
    /**
     * Gets an id to an individual queue
     *
     * @return the id to the queue
     */
    protected int getQueueId() {
        if (_qID == -1) {
            _qID = getQueue().getQueue();
            _logger.write(toString(), Logger.DEBUG, "Assigned Queue - " + _qID);
        }
        return _qID;
    }

    /**
     * Returns the "friendly" name of this class. This
     * is simply an accessor for _name, required due to
     * inheritance issues with extending AlerterSkeleton.
     *
     * @return the friendly name
     */
    protected abstract String getFName();

//---ATTRIBUTES---

    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    protected String _name = "AlerterSkeleton";

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    protected Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
     * A reference to the singleton configuration proxy
     * in use, through which alerter configuration can be obtained
     */
    protected ConfigurationProxy _cp = ConfigurationProxy.getInstance();
    
    /**
     * The ID of the queue the alerter will use.
     * Initially -1, but initialised on first use.
     */
    protected int _qID = -1;
    
    /**
     * The state of the alerter thread
     */
    protected boolean _running = true;

//---STATIC ATTRIBUTES---

}
Revision:	1.14
Committed:	Sun Sep 25 09:57:40 2005 UTC (18 years, 7 months ago) by tdb
Branch:	MAIN
CVS Tags:	HEAD
Changes since 1.13:	+4 -3 lines
Log Message:	Fix compile problems on j2se 1.5 - our Queue class conflicted with one in java.util. Also fix an API issue when running the server on Windows - the println method sends '\r\n' on Windows instead of '\n' on Unix, which confuses applications such as ihost. Patch provided by: skel
#	Content
1	/*
2	* i-scream central monitoring system
3	* http://www.i-scream.org
4	* Copyright (C) 2000-2002 i-scream
5	*
6	* This program is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU General Public License
8	* as published by the Free Software Foundation; either version 2
9	* of the License, or (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19	*/
20
21	//---PACKAGE DECLARATION---
22	package uk.org.iscream.cms.server.client;
23
24	//---IMPORTS---
25	import uk.org.iscream.cms.server.client.*;
26	import uk.org.iscream.cms.server.core.*;
27	import uk.org.iscream.cms.util.*;
28	import uk.org.iscream.cms.server.componentmanager.*;
29	import java.text.*;
30	import java.util.Date;
31	import java.util.Locale;
32
33	/**
34	* Skeleton class for Alerters
35	* This skeleton reads alerts from the alert queue designated
36	* to the Alerter, it then feeds the alerts to the sendAlert
37	* method, which the extending class should implement. The class
38	* should then handle sending the message. This class also has a
39	* method to allow formatting of messages.
40	*
41	* @author $Author: tdb $
42	* @version $Id: AlerterSkeleton.java,v 1.13 2004/08/01 10:40:40 tdb Exp $
43	*/
44	public abstract class AlerterSkeleton extends Thread implements PluginAlerter {
45
46	//---FINAL ATTRIBUTES---
47
48	/**
49	* The current CVS revision of this class
50	*/
51	public final String REVISION = "$Revision: 1.13 $";
52
53	/**
54	* The default level to send alerts at
55	*/
56	public final String DEFAULT_LEVEL = Alert.alertLevels[0];
57
58	/**
59	* If a configuration property is not
60	* configured, this will be used instead.
61	*/
62	public final String NOT_CONFIGURED = "<NOT CONFIGURED>";
63
64	//---STATIC METHODS---
65
66	//---CONSTRUCTORS---
67
68	/**
69	* Constructs and starts the alerter reading alerts
70	*/
71	public AlerterSkeleton() {
72	_logger.write(toString(), Logger.SYSINIT, "started.");
73	this.start();
74	}
75
76	//---PUBLIC METHODS---
77
78	/**
79	* Reads the next alert from the alerter queue for this
80	* alerter. It then looks up Alerter.<alerter name>.level in
81	* the configuration to determine the lowest level of alert
82	* the extending alerter should send. If the alert is
83	* above this level, or if the alert is an OK for an alert
84	* escalation which did rise above this alerters level, it then
85	* calls sendAlert to tell the alerter to send the alert. If it
86	* isn't above this level, it ignores the alert.
87	*/
88	public void run() {
89	while(_running) {
90	try {
91	Alert alert = (Alert) getQueue().get(getQueueId());
92	String levelName;
93	try {
94	levelName = _cp.getProperty(_name, "Alerter." + getFName() + ".level");
95	} catch (PropertyNotFoundException e) {
96	levelName = DEFAULT_LEVEL;
97	_logger.write(toString(), Logger.WARNING, "Alerter." + getFName() + ".level value unavailable using default of " + levelName);
98	}
99	int level = StringUtils.getStringPos(levelName, Alert.alertLevels);
100	// only send if it's equal (or above) our level
101	if(((alert.getLevel() == 0) && (alert.getLastLevel() >= level)) \|\| (alert.getLevel() >= level)) {
102	sendAlert(alert);
103	}
104	} catch (InvalidQueueException e) {
105	_logger.write(this.toString(), Logger.ERROR, "Unable to get queue.");
106	}
107	}
108	}
109
110	/**
111	* Sends an alert object using whatever transport
112	* mechanism the extending class is implementing.
113	*
114	* @param alert the Alert to send
115	*/
116	protected abstract void sendAlert(Alert alert);
117
118	/**
119	* Processes a message, replace key fields (eg. %level%) with
120	* representative text from the given Alert object.
121	*
122	* @param message The message to process
123	* @param alert The Alert object to get data from
124	* @return the processed message
125	*/
126	protected String processAlertMessage(String message, Alert alert) {
127	// get some values
128	String alertType = Alert.alertLevels[alert.getLevel()];
129	String thresholdType = Alert.thresholdLevels[alert.getThreshold()];
130	String timeSinceFirst = DateUtils.formatTime((System.currentTimeMillis() - alert.getInitialAlertTime())/1000, "%DAYS% days, %HOURS% hours, %MINS% mins, and %SECS% secs");
131	String timeFirstOccured = DateFormat.getDateTimeInstance(DateFormat.SHORT, DateFormat.SHORT, Locale.UK).format(new Date(alert.getInitialAlertTime()));
132
133	// replace fields in message
134	message = StringUtils.replaceText(message, "%level%", alertType);
135	message = StringUtils.replaceText(message, "%threshold%", thresholdType);
136	message = StringUtils.replaceText(message, "%source%", alert.getSource());
137	message = StringUtils.replaceText(message, "%value%", alert.getValue());
138	message = StringUtils.replaceText(message, "%thresholdValue%", alert.getThresholdValue());
139	message = StringUtils.replaceText(message, "%attributeName%", alert.getAttributeName());
140	message = StringUtils.replaceText(message, "%timeTillNextAlert%", DateUtils.getTimeString(Long.parseLong(alert.getTimeTillNextAlert())));
141	message = StringUtils.replaceText(message, "%timeSinceFirstAlert%", timeSinceFirst);
142	message = StringUtils.replaceText(message, "%timeOfFirstAlert%", timeFirstOccured);
143	return message;
144	}
145
146	/**
147	* Return the String representation of what the alerter does
148	*
149	* @return the description
150	*/
151	public abstract String getDescription();
152
153
154	//---PRIVATE METHODS---
155
156	//---ACCESSOR/MUTATOR METHODS---
157
158	/**
159	* Gets hold of the Alerts queue from the AlerterManager.
160	*
161	* @return The Alerts queue
162	*/
163	protected Queue getQueue() {
164	return AlerterManager.getInstance().getQueue();
165	}
166
167	/**
168	* Gets an id to an individual queue
169	*
170	* @return the id to the queue
171	*/
172	protected int getQueueId() {
173	if (_qID == -1) {
174	_qID = getQueue().getQueue();
175	_logger.write(toString(), Logger.DEBUG, "Assigned Queue - " + _qID);
176	}
177	return _qID;
178	}
179
180	/**
181	* Returns the "friendly" name of this class. This
182	* is simply an accessor for _name, required due to
183	* inheritance issues with extending AlerterSkeleton.
184	*
185	* @return the friendly name
186	*/
187	protected abstract String getFName();
188
189	//---ATTRIBUTES---
190
191	/**
192	* This is the friendly identifier of the
193	* component this class is running in.
194	* eg, a Filter may be called "filter1",
195	* If this class does not have an owning
196	* component, a name from the configuration
197	* can be placed here. This name could also
198	* be changed to null for utility classes.
199	*/
200	protected String _name = "AlerterSkeleton";
201
202	/**
203	* This holds a reference to the
204	* system logger that is being used.
205	*/
206	protected Logger _logger = ReferenceManager.getInstance().getLogger();
207
208	/**
209	* A reference to the singleton configuration proxy
210	* in use, through which alerter configuration can be obtained
211	*/
212	protected ConfigurationProxy _cp = ConfigurationProxy.getInstance();
213
214	/**
215	* The ID of the queue the alerter will use.
216	* Initially -1, but initialised on first use.
217	*/
218	protected int _qID = -1;
219
220	/**
221	* The state of the alerter thread
222	*/
223	protected boolean _running = true;
224
225	//---STATIC ATTRIBUTES---
226
227	}