001/*
002 * CDDL HEADER START
003 *
004 * The contents of this file are subject to the terms of the
005 * Common Development and Distribution License, Version 1.0 only
006 * (the "License").  You may not use this file except in compliance
007 * with the License.
008 *
009 * You can obtain a copy of the license at
010 * docs/licenses/cddl.txt
011 * or http://www.opensource.org/licenses/cddl1.php.
012 * See the License for the specific language governing permissions
013 * and limitations under the License.
014 *
015 * When distributing Covered Code, include this CDDL HEADER in each
016 * file and include the License file at
017 * docs/licenses/cddl.txt.  If applicable,
018 * add the following below this CDDL HEADER, with the fields enclosed
019 * by brackets "[]" replaced with your own identifying information:
020 *      Portions Copyright [yyyy] [name of copyright owner]
021 *
022 * CDDL HEADER END
023 *
024 *
025 *      Copyright 2010-2016 UnboundID Corp.
026 */
027package com.unboundid.directory.sdk.common.api;
028
029
030
031import java.util.Collections;
032import java.util.List;
033import java.util.Map;
034
035import com.unboundid.directory.sdk.broker.internal.BrokerExtension;
036import com.unboundid.directory.sdk.common.config.AlertHandlerConfig;
037import com.unboundid.directory.sdk.common.internal.ExampleUsageProvider;
038import com.unboundid.directory.sdk.common.internal.Reconfigurable;
039import com.unboundid.directory.sdk.common.internal.UnboundIDExtension;
040import com.unboundid.directory.sdk.common.types.AlertNotification;
041import com.unboundid.directory.sdk.common.types.ServerContext;
042import com.unboundid.directory.sdk.ds.internal.DirectoryServerExtension;
043import com.unboundid.directory.sdk.metrics.internal.MetricsEngineExtension;
044import com.unboundid.directory.sdk.proxy.internal.DirectoryProxyServerExtension;
045import com.unboundid.directory.sdk.sync.internal.SynchronizationServerExtension;
046import com.unboundid.ldap.sdk.LDAPException;
047import com.unboundid.ldap.sdk.ResultCode;
048import com.unboundid.util.Extensible;
049import com.unboundid.util.ThreadSafety;
050import com.unboundid.util.ThreadSafetyLevel;
051import com.unboundid.util.args.ArgumentException;
052import com.unboundid.util.args.ArgumentParser;
053
054
055
056/**
057 * This class defines an API that must be implemented by extensions which will
058 * be invoked whenever an administrative alert is generated within the server.
059 * Administrative alerts may be used to notify administrators whenever a
060 * significant error, warning, or other type of event occurs within the server.
061 * Alert handlers may be used to help ensure that those notifications are made
062 * available to administrators in an appropriate manner.
063 * <BR><BR>
064 * Each alert handler may be configured so that it will only be invoked for
065 * certain types of alerts, either based on the specific alert type or based on
066 * the alert severity.  This is handled automatically by the server, so
067 * individual alert handler implementations do not need to attempt to perform
068 * that filtering on their own.  However, they may perform additional processing
069 * if desired to further narrow the set of alerts that should be made available
070 * to administrators.
071 * <BR>
072 * <H2>Configuring Alert Handlers</H2>
073 * In order to configure an alert handler created using this API, use a command
074 * like:
075 * <PRE>
076 *      dsconfig create-alert-handler \
077 *           --handler-name "<I>{handler-name}</I>" \
078 *           --type third-party \
079 *           --set enabled:true \
080 *           --set "extension-class:<I>{class-name}</I>" \
081 *           --set "extension-argument:<I>{name=value}</I>"
082 * </PRE>
083 * where "<I>{handler-name}</I>" is the name to use for the alert handler
084 * instance, "<I>{class-name}</I>" is the fully-qualified name of the Java class
085 * that extends {@code com.unboundid.directory.sdk.common.api.AlertHandler},
086 * and "<I>{name=value}</I>" represents name-value pairs for any arguments to
087 * provide to the alert handler.  If multiple arguments should be provided to
088 * the alert handler, then the
089 * "<CODE>--set extension-argument:<I>{name=value}</I></CODE>" option should be
090 * provided multiple times.
091 *
092 * @see  com.unboundid.directory.sdk.common.scripting.ScriptedAlertHandler
093 */
094@Extensible()
095@DirectoryServerExtension()
096@DirectoryProxyServerExtension(appliesToLocalContent=true,
097     appliesToRemoteContent=false)
098@SynchronizationServerExtension(appliesToLocalContent=true,
099     appliesToSynchronizedContent=false)
100@MetricsEngineExtension()
101@BrokerExtension()
102@ThreadSafety(level=ThreadSafetyLevel.INTERFACE_THREADSAFE)
103public abstract class AlertHandler
104       implements UnboundIDExtension, Reconfigurable<AlertHandlerConfig>,
105                  ExampleUsageProvider
106{
107  /**
108   * Creates a new instance of this alert handler.  All alert handler
109   * implementations must include a default constructor, but any initialization
110   * should generally be done in the {@code initializeAlertHandler} method.
111   */
112  public AlertHandler()
113  {
114    // No implementation is required.
115  }
116
117
118
119  /**
120   * {@inheritDoc}
121   */
122  public abstract String getExtensionName();
123
124
125
126  /**
127   * {@inheritDoc}
128   */
129  public abstract String[] getExtensionDescription();
130
131
132
133  /**
134   * {@inheritDoc}
135   */
136  public void defineConfigArguments(final ArgumentParser parser)
137         throws ArgumentException
138  {
139    // No arguments will be allowed by default.
140  }
141
142
143
144  /**
145   * Initializes this alert handler.
146   *
147   * @param  serverContext  A handle to the server context for the server in
148   *                        which this extension is running.
149   * @param  config         The general configuration for this alert handler.
150   * @param  parser         The argument parser which has been initialized from
151   *                        the configuration for this alert handler.
152   *
153   * @throws  LDAPException  If a problem occurs while initializing this alert
154   *                         handler.
155   */
156  public void initializeAlertHandler(final ServerContext serverContext,
157                                     final AlertHandlerConfig config,
158                                     final ArgumentParser parser)
159         throws LDAPException
160  {
161    // No initialization will be performed by default.
162  }
163
164
165
166  /**
167   * {@inheritDoc}
168   */
169  public boolean isConfigurationAcceptable(final AlertHandlerConfig config,
170                      final ArgumentParser parser,
171                      final List<String> unacceptableReasons)
172  {
173    // No extended validation will be performed by default.
174    return true;
175  }
176
177
178
179  /**
180   * {@inheritDoc}
181   */
182  public ResultCode applyConfiguration(final AlertHandlerConfig config,
183                                       final ArgumentParser parser,
184                                       final List<String> adminActionsRequired,
185                                       final List<String> messages)
186  {
187    // By default, no configuration changes will be applied.  If there are any
188    // arguments, then add an admin action message indicating that the extension
189    // needs to be restarted for any changes to take effect.
190    if (! parser.getNamedArguments().isEmpty())
191    {
192      adminActionsRequired.add(
193           "No configuration change has actually been applied.  The new " +
194                "configuration will not take effect until this alert handler " +
195                "is disabled and re-enabled or until the server is restarted.");
196    }
197
198    return ResultCode.SUCCESS;
199  }
200
201
202
203  /**
204   * Performs any cleanup which may be necessary when this alert handler is to
205   * be taken out of service.
206   */
207  public void finalizeAlertHandler()
208  {
209    // No implementation is required.
210  }
211
212
213
214  /**
215   * Performs any processing which may be necessary to handle the provided alert
216   * notification.
217   *
218   * @param  alert  The alert notification generated within the server.
219   */
220  public abstract void handleAlert(final AlertNotification alert);
221
222
223
224  /**
225   * {@inheritDoc}
226   */
227  public Map<List<String>,String> getExamplesArgumentSets()
228  {
229    return Collections.emptyMap();
230  }
231}