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 2010-2012 UnboundID Corp.
026 */
027 package com.unboundid.directory.sdk.ds.api;
028
029
030
031 import java.util.Collections;
032 import java.util.List;
033 import java.util.Map;
034
035 import com.unboundid.directory.sdk.common.internal.ExampleUsageProvider;
036 import com.unboundid.directory.sdk.common.internal.Reconfigurable;
037 import com.unboundid.directory.sdk.common.internal.UnboundIDExtension;
038 import com.unboundid.directory.sdk.common.types.OperationContext;
039 import com.unboundid.directory.sdk.common.types.Entry;
040 import com.unboundid.directory.sdk.ds.config.VirtualAttributeProviderConfig;
041 import com.unboundid.directory.sdk.ds.internal.DirectoryServerExtension;
042 import com.unboundid.directory.sdk.ds.scripting.
043 ScriptedVirtualAttributeProvider;
044 import com.unboundid.directory.sdk.ds.types.DirectoryServerContext;
045 import com.unboundid.directory.sdk.proxy.internal.DirectoryProxyServerExtension;
046 import com.unboundid.directory.sdk.sync.internal.SynchronizationServerExtension;
047 import com.unboundid.ldap.sdk.Attribute;
048 import com.unboundid.ldap.sdk.LDAPException;
049 import com.unboundid.ldap.sdk.ResultCode;
050 import com.unboundid.util.Extensible;
051 import com.unboundid.util.ThreadSafety;
052 import com.unboundid.util.ThreadSafetyLevel;
053 import com.unboundid.util.args.ArgumentException;
054 import com.unboundid.util.args.ArgumentParser;
055
056
057
058 /**
059 * This class defines an API that must be implemented by extensions which
060 * construct attribute values which may be included in entries instead of or
061 * in addition to real values which are actually stored in the backend. The
062 * other attributes in the entry will be available for use in the process of
063 * generating the entry, and internal or external operations may also be
064 * performed if the generated values should incorporate data from other
065 * locations.
066 * <BR><BR>
067 * Each virtual attribute provider may be configured to indicate whether the
068 * associated virtual attribute should be included in a given entry. This
069 * criteria may include the entry's location in the DIT, whether it matches a
070 * given filter, whether it is a member of a specified group, and whether the
071 * requesting client has been assigned a given client connection policy. This
072 * is handled automatically by the server, so individual virtual attribute
073 * provider implementations do not need to attempt to perform that filtering on
074 * their own. However, they may perform additional processing if desired to
075 * further narrow the set of entries for which the virtual attribute should be
076 * generated.
077 * <BR><BR>
078 * In addition, virtual attribute providers may be configured to indicate the
079 * behavior that should be exhibited in the event that the target attribute
080 * already exists in the entry with one or more real values. In this case, the
081 * real values may be used instead of generating virtual values, the virtual
082 * values may be used in place of the real values, or both the real and virtual
083 * values may be merged and presented together. This work is also automatically
084 * performed by the server, so virtual attribute providers do not need to do any
085 * processing to determine whether to generate a value based on whether the
086 * target attribute already exists in the entry.
087 * <BR><BR>
088 * Note that at most one virtual attribute provider may be used to generate a
089 * value for the same attribute in any entry. If multiple virtual attribute
090 * providers are configured to generate values for the same attribute, then they
091 * should also be configured with different sets of criteria so that they will
092 * only be used for different sets of entries. If multiple virtual attribute
093 * providers targeting the same attribute apply to the same entry, then only
094 * one of them will be used, and it is undefined which one will be selected.
095 * <BR>
096 * <H2>Configuring Virtual Attribute Providers</H2>
097 * In order to configure a virtual attribute provider created using this API,
098 * use a command like:
099 * <PRE>
100 * dsconfig create-virtual-attribute \
101 * --name "<I>{name}</I>" \
102 * --type third-party \
103 * --set enabled:true \
104 * --set attribute-type:{attribute} \
105 * --set "extension-class:<I>{class-name}</I>" \
106 * --set "extension-argument:<I>{name=value}</I>"
107 * </PRE>
108 * where "<I>{name}</I>" is the name to use for the virtual attribute provider
109 * instance, "<I>{attribute}</I>" is the name of the attribute for which the
110 * virtual attribute provider should be used to generate values,
111 * "<I>{class-name}</I>" is the fully-qualified name of the Java class that
112 * extends {@code com.unboundid.directory.sdk.ds.api.VirtualAttributeProvider},
113 * and "<I>{name=value}</I>" represents name-value pairs for any arguments to
114 * provide to the virtual attribute provider. If multiple arguments should be
115 * provided to the virtual attribute provider, then the
116 * "<CODE>--set extension-argument:<I>{name=value}</I></CODE>" option should be
117 * provided multiple times.
118 *
119 * @see ScriptedVirtualAttributeProvider
120 */
121 @Extensible()
122 @DirectoryServerExtension()
123 @DirectoryProxyServerExtension(appliesToLocalContent=true,
124 appliesToRemoteContent=false)
125 @SynchronizationServerExtension(appliesToLocalContent=true,
126 appliesToSynchronizedContent=false)
127 @ThreadSafety(level=ThreadSafetyLevel.INTERFACE_THREADSAFE)
128 public abstract class VirtualAttributeProvider
129 implements UnboundIDExtension,
130 Reconfigurable<VirtualAttributeProviderConfig>,
131 ExampleUsageProvider
132 {
133 /**
134 * Creates a new instance of this virtual attribute provider. All virtual
135 * attribute provider implementations must include a default constructor, but
136 * any initialization should generally be done in the
137 * {@code initializeVirtualAttributeProvider} method.
138 */
139 public VirtualAttributeProvider()
140 {
141 // No implementation is required. However, we need to reference the
142 // scripted virtual attribute provider so that checkstyle is satisfied with
143 // the import.
144 final ScriptedVirtualAttributeProvider scriptedProvider = null;
145 }
146
147
148
149 /**
150 * {@inheritDoc}
151 */
152 public abstract String getExtensionName();
153
154
155
156 /**
157 * {@inheritDoc}
158 */
159 public abstract String[] getExtensionDescription();
160
161
162
163 /**
164 * {@inheritDoc}
165 */
166 public void defineConfigArguments(final ArgumentParser parser)
167 throws ArgumentException
168 {
169 // No arguments will be allowed by default.
170 }
171
172
173
174 /**
175 * Initializes this virtual attribute provider.
176 *
177 * @param serverContext A handle to the server context for the server in
178 * which this extension is running.
179 * @param config The general configuration for this virtual attribute
180 * provider.
181 * @param parser The argument parser which has been initialized from
182 * the configuration for this virtual attribute
183 * provider.
184 *
185 * @throws LDAPException If a problem occurs while initializing this virtual
186 * attribute provider.
187 */
188 public void initializeVirtualAttributeProvider(
189 final DirectoryServerContext serverContext,
190 final VirtualAttributeProviderConfig config,
191 final ArgumentParser parser)
192 throws LDAPException
193 {
194 // No initialization will be performed by default.
195 }
196
197
198
199 /**
200 * {@inheritDoc}
201 */
202 public boolean isConfigurationAcceptable(
203 final VirtualAttributeProviderConfig config,
204 final ArgumentParser parser,
205 final List<String> unacceptableReasons)
206 {
207 // No extended validation will be performed by default.
208 return true;
209 }
210
211
212
213 /**
214 * {@inheritDoc}
215 */
216 public ResultCode applyConfiguration(
217 final VirtualAttributeProviderConfig config,
218 final ArgumentParser parser,
219 final List<String> adminActionsRequired,
220 final List<String> messages)
221 {
222 // By default, no configuration changes will be applied. If there are any
223 // arguments, then add an admin action message indicating that the extension
224 // needs to be restarted for any changes to take effect.
225 if (! parser.getNamedArguments().isEmpty())
226 {
227 adminActionsRequired.add(
228 "No configuration change has actually been applied. The new " +
229 "configuration will not take effect until this virtual " +
230 "attribute provider is disabled and re-enabled or until the " +
231 "server is restarted.");
232 }
233
234 return ResultCode.SUCCESS;
235 }
236
237
238
239 /**
240 * Performs any cleanup which may be necessary when this virtual attribute
241 * provider is to be taken out of service.
242 */
243 public void finalizeVirtualAttributeProvider()
244 {
245 // No implementation is required.
246 }
247
248
249
250 /**
251 * Indicates whether the server may cache values generated by this virtual
252 * attribute provider for reuse against the same entry in the course of
253 * processing the same operation.
254 *
255 * @return {@code true} if the server may cache the value generated by this
256 * virtual attribute provider for reuse with the same entry in the
257 * same operation, or {@code false} if not.
258 */
259 public boolean mayCacheInOperation()
260 {
261 return false;
262 }
263
264
265
266 /**
267 * Indicates whether this virtual attribute provider may generate attributes
268 * with multiple values.
269 *
270 * @return {@code true} if this virtual attribute provider may generate
271 * attributes with multiple values, or {@code false} if it will only
272 * generate single-valued attributes.
273 */
274 public abstract boolean isMultiValued();
275
276
277
278 /**
279 * Generates an attribute for inclusion in the provided entry.
280 *
281 * @param operationContext The operation context for the operation in
282 * progress, if any. It may be {@code null} if no
283 * operation is available.
284 * @param entry The entry for which the attribute is to be
285 * generated.
286 * @param attributeName The name of the attribute to be generated.
287 *
288 * @return The generated attribute, or {@code null} if no attribute should be
289 * generated.
290 */
291 public abstract Attribute generateAttribute(
292 final OperationContext operationContext,
293 final Entry entry, final String attributeName);
294
295
296
297 /**
298 * {@inheritDoc}
299 */
300 public Map<List<String>,String> getExamplesArgumentSets()
301 {
302 return Collections.emptyMap();
303 }
304 }