/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cocoon.acting;
import org.apache.avalon.framework.configuration.Configurable;
import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.avalon.framework.parameters.Parameters;
import org.apache.avalon.framework.service.ServiceSelector;
import org.apache.avalon.framework.thread.ThreadSafe;
import org.apache.cocoon.components.modules.output.OutputModule;
import org.apache.cocoon.environment.Redirector;
import org.apache.cocoon.environment.SourceResolver;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* This is the action used to propagate parameters into a store using an
* {@link org.apache.cocoon.components.modules.output.OutputModule}. It
* simply propagates given expression. Additionaly it will make all propagated values
* available via returned Map.
*
* <p>Example configuration:</p>
* <pre>
* <map:action type="...." name="...." logger="...">
* <output-module name="session-attr">
* <!-- optional configuration for output module -->
* </output-module>
* <store-empty-parameters>true</store-empty-parameters>
* <defaults>
* <default name="..." value="...."/>
* <default name="..." value="..."/>
* </defaults>
* </map:action>
* </pre>
*
* <p>Example use:</p>
* <pre>
* <map:act type="session-propagator">
* <paramater name="example" value="{example}"/>
* <paramater name="example1" value="xxx"/>
* <parameter name="PropagatorAction:store-empty-parameters" value="true"/>
* <parameter name="PropagatorAction:output-module" value="session-attr"/>
* </map:act>
* </pre>
*
* <h3>Configuration</h3>
* <table><tbody>
* <tr>
* <th>output-module</th>
* <td>Nested element configuring output to use. Name attribute holds
* output module hint.</td>
* <td></td><td>XML</td><td><code>request-attr</code></td>
* </tr>
* <tr>
* <th>store-empty-parameters</th>
* <td>Propagate parameters with empty values.</td>
* <td></td><td>boolean</td><td><code>true</code></td>
* </tr>
* <tr>
* <th>defaults</th>
* <td>Parent for default parameters to propagate.</td>
* <td></td><td>XML</td><td></td>
* </tr>
* <tr>
* <th>defaults/default</th>
* <td>Name attribute holds parameter name, value attribute holds
* parameter value. Will be used when not set on use.</td>
* <td></td><td>parameter</td><td></td>
* </tr>
* </tbody></table>
*
*<h3>Parameters</h3>
* <table><tbody>
* <tr>
* <th>PropagatorAction:output-module</th>
* <td>Alternative output module hint to use. A <code>null</code> configuration
* will be passed to a module selected this way.</td>
* <td></td><td>String</td><td>as determined by configuration</td>
* </tr>
* <tr>
* <th>PropagatorAction:store-empty-parameters</th>
* <td>Propagate parameters with empty values.</td>
* <td></td><td>boolean</td><td>as determined by configuration</td>
* </tr>
* <tr>
* <th>any other</th>
* <td>Any other parameter will be propagated.</td>
* <td></td><td>String</td><td></td>
* </tr>
* </tbody></table>
*
* @author <a href="mailto:haul@apache.org">Christian Haul</a>
* @author <a href="mailto:Martin.Man@seznam.cz">Martin Man</a>
* @version CVS $Id: PropagatorAction.java 433543 2006-08-22 06:22:54Z crossley $
*/
public class PropagatorAction extends ServiceableAction
implements Configurable, ThreadSafe {
/** Prefix for sitemap parameters targeted at this action. */
private static final String ACTION_PREFIX = "PropagatorAction:";
/** Configuration parameter name. */
private static final String CONFIG_STORE_EMPTY = "store-empty-parameters";
/** Configuration parameter name. */
private static final String CONFIG_OUTPUT_MODULE = "output-module";
/** Default output module name. */
private static final String OUTPUT_HINT = "request-attr"; // defaults to request attributes
/** Should empty parameter values be propagated? */
private boolean storeEmpty = true;
/** Configuration object for output module. */
private Configuration outputConf;
/** Name of output module to use. */
private String outputName;
/** List of {@link Entry}s holding default values. */
private List defaults;
/**
* A private helper holding default parameter entries.
*
*/
private static class Entry {
public String key;
public String value;
public Entry(String key, String value) {
this.key = key;
this.value = value;
}
}
/* (non-Javadoc)
* @see org.apache.avalon.framework.configuration.Configurable#configure(org.apache.avalon.framework.configuration.Configuration)
*/
public void configure(Configuration config) throws ConfigurationException {
this.outputConf = config.getChild(CONFIG_OUTPUT_MODULE);
this.outputName = this.outputConf.getAttribute("name", OUTPUT_HINT);
this.storeEmpty =
config.getChild(CONFIG_STORE_EMPTY).getValueAsBoolean(this.storeEmpty);
Configuration[] dflts = config.getChild("defaults").getChildren("default");
if (dflts != null) {
this.defaults = new ArrayList(dflts.length);
for (int i = 0; i < dflts.length; i++) {
this.defaults.add(
new Entry(dflts[i].getAttribute("name"),
dflts[i].getAttribute("value")));
}
} else {
this.defaults = new ArrayList(0);
}
}
/* (non-Javadoc)
* @see org.apache.cocoon.acting.Action#act(Redirector, SourceResolver, Map, String, Parameters)
*/
public Map act(Redirector redirector,
SourceResolver resolver,
Map objectModel,
String source,
Parameters parameters)
throws Exception {
// Read action parameters
String outputName = parameters.getParameter(ACTION_PREFIX + CONFIG_OUTPUT_MODULE,
null);
boolean storeEmpty = parameters.getParameterAsBoolean(ACTION_PREFIX + CONFIG_STORE_EMPTY,
this.storeEmpty);
parameters.removeParameter(ACTION_PREFIX + CONFIG_OUTPUT_MODULE);
parameters.removeParameter(ACTION_PREFIX + CONFIG_STORE_EMPTY);
Configuration outputConf = null;
if (outputName == null) {
outputName = this.outputName;
outputConf = this.outputConf;
}
// Action results map
final Map results = new HashMap();
OutputModule output = null;
ServiceSelector selector = null;
try {
selector = (ServiceSelector) this.manager.lookup(OutputModule.ROLE + "Selector");
if (outputName != null
&& selector != null
&& selector.isSelectable(outputName)) {
output = (OutputModule) selector.select(outputName);
String[] names = parameters.getNames();
for (int i = 0; i < names.length; i++) {
String name = names[i];
String value = parameters.getParameter(name);
if (storeEmpty || (value != null && !value.equals(""))) {
if (getLogger().isDebugEnabled()) {
getLogger().debug("Propagating <" + name + "> value <" + value + ">");
}
output.setAttribute(outputConf,
objectModel,
name,
value);
results.put(name, value);
}
}
// Defaults, that are not overridden
for (Iterator i = defaults.iterator(); i.hasNext();) {
Entry entry = (Entry) i.next();
if (!results.containsKey(entry.key)) {
if (getLogger().isDebugEnabled()) {
getLogger().debug("Propagating default <" + entry.key + "> value <" + entry.value + ">");
}
output.setAttribute(outputConf,
objectModel,
entry.key,
entry.value);
results.put(entry.key, entry.value);
}
}
output.commit(outputConf, objectModel);
}
} catch (Exception e) {
if (output != null) {
output.rollback(outputConf, objectModel, e);
}
throw e;
} finally {
if (selector != null) {
if (output != null) {
selector.release(output);
}
this.manager.release(selector);
}
}
return Collections.unmodifiableMap(results);
}
}