org.apache.velocity.runtime.directive.Parse Maven / Gradle / Ivy
The newest version!
package org.apache.velocity.runtime.directive;
/*
* 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.
*/
import org.apache.velocity.Template;
import org.apache.velocity.app.event.EventHandlerUtil;
import org.apache.velocity.context.InternalContextAdapter;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.apache.velocity.exception.TemplateInitException;
import org.apache.velocity.exception.VelocityException;
import org.apache.velocity.runtime.RuntimeConstants;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.runtime.parser.ParseException;
import org.apache.velocity.runtime.parser.Token;
import org.apache.velocity.runtime.parser.node.Node;
import org.apache.velocity.runtime.parser.node.ParserTreeConstants;
import org.apache.velocity.runtime.parser.node.SimpleNode;
import org.apache.velocity.util.StringUtils;
import java.io.IOException;
import java.io.Writer;
import java.util.ArrayList;
import java.util.List;
/**
* Pluggable directive that handles the #parse()
* statement in VTL.
*
*
* Notes:
* -----
* 1) The parsed source material can only come from somewhere in
* the TemplateRoot tree for security reasons. There is no way
* around this. If you want to include content from elsewhere on
* your disk, use a link from somewhere under Template Root to that
* content.
*
* 2) There is a limited parse depth. It is set as a property
* "directive.parse.max_depth = 10" by default. This 10 deep
* limit is a safety feature to prevent infinite loops.
*
*
* @author Geir Magnusson Jr.
* @author Jason van Zyl
* @author Christoph Reck
* @version $Id$
*/
public class Parse extends InputBase
{
private int maxDepth;
/**
* Indicates if we are running in strict reference mode.
*/
public boolean strictRef = false;
/**
* Return name of this directive.
* @return The name of this directive.
*/
@Override
public String getName()
{
return "parse";
}
/**
* Overrides the default to use "template", so that all templates
* can use the same scope reference, whether rendered via #parse
* or direct merge.
*/
@Override
public String getScopeName()
{
return "template";
}
/**
* Return type of this directive.
* @return The type of this directive.
*/
@Override
public int getType()
{
return LINE;
}
/**
* Init's the #parse directive.
* @param rs
* @param context
* @param node
* @throws TemplateInitException
*/
@Override
public void init(RuntimeServices rs, InternalContextAdapter context, Node node)
throws TemplateInitException
{
super.init(rs, context, node);
this.maxDepth = rsvc.getInt(RuntimeConstants.PARSE_DIRECTIVE_MAXDEPTH, 10);
strictRef = rsvc.getBoolean(RuntimeConstants.RUNTIME_REFERENCES_STRICT, false);
}
/**
* iterates through the argument list and renders every
* argument that is appropriate. Any non appropriate
* arguments are logged, but render() continues.
* @param context
* @param writer
* @param node
* @return True if the directive rendered successfully.
* @throws IOException
* @throws ResourceNotFoundException
* @throws ParseErrorException
* @throws MethodInvocationException
*/
@Override
public boolean render(InternalContextAdapter context,
Writer writer, Node node)
throws IOException, ResourceNotFoundException, ParseErrorException,
MethodInvocationException
{
/*
* did we get an argument?
*/
if ( node.jjtGetNumChildren() == 0 )
{
throw new VelocityException("#parse(): argument missing at " +
StringUtils.formatFileString(this), null, rsvc.getLogContext().getStackTrace());
}
/*
* does it have a value? If you have a null reference, then no.
*/
Object value = node.jjtGetChild(0).value( context );
if (value == null)
{
log.debug("#parse(): null argument at {}", StringUtils.formatFileString(this));
}
/*
* get the path
*/
String sourcearg = value == null ? null : value.toString();
/*
* check to see if the argument will be changed by the event cartridge
*/
String arg = EventHandlerUtil.includeEvent( rsvc, context, sourcearg, context.getCurrentTemplateName(), getName());
/*
* if strict mode and arg was not fixed by event handler, then complain
*/
if (strictRef && value == null && arg == null)
{
throw new VelocityException("The argument to #parse returned null at "
+ StringUtils.formatFileString(this), null, rsvc.getLogContext().getStackTrace());
}
/*
* a null return value from the event cartridge indicates we should not
* input a resource.
*/
if (arg == null)
{
// abort early, but still consider it a successful rendering
return true;
}
if (maxDepth > 0)
{
/*
* see if we have exceeded the configured depth.
*/
String[] templateStack = context.getTemplateNameStack();
if (templateStack.length >= maxDepth)
{
StringBuilder path = new StringBuilder();
for (String aTemplateStack : templateStack)
{
path.append(" > ").append(aTemplateStack);
}
log.error("Max recursion depth reached ({}). File stack: {}",
templateStack.length, path);
return false;
}
}
/*
* now use the Runtime resource loader to get the template
*/
Template t = null;
try
{
t = rsvc.getTemplate( arg, getInputEncoding(context) );
}
catch ( ResourceNotFoundException rnfe )
{
/*
* the arg wasn't found. Note it and throw
*/
log.error("#parse(): cannot find template '{}', called at {}",
arg, StringUtils.formatFileString(this));
throw rnfe;
}
catch ( ParseErrorException pee )
{
/*
* the arg was found, but didn't parse - syntax error
* note it and throw
*/
log.error("#parse(): syntax error in #parse()-ed template '{}', called at {}",
arg, StringUtils.formatFileString(this));
throw pee;
}
/*
* pass through application level runtime exceptions
*/
catch( RuntimeException e )
{
log.error("Exception rendering #parse({}) at {}",
arg, StringUtils.formatFileString(this));
throw e;
}
catch ( Exception e )
{
String msg = "Exception rendering #parse(" + arg + ") at " +
StringUtils.formatFileString(this);
log.error(msg, e);
throw new VelocityException(msg, e, rsvc.getLogContext().getStackTrace());
}
/*
* Add the template name to the macro libraries list
*/
List macroLibraries = context.getMacroLibraries();
/*
* if macroLibraries are not set create a new one
*/
if (macroLibraries == null)
{
macroLibraries = new ArrayList<>();
}
context.setMacroLibraries(macroLibraries);
/* instead of adding the name of the template, add the Template reference */
macroLibraries.add(t);
/*
* and render it
*/
try
{
preRender(context);
context.pushCurrentTemplateName(arg);
((SimpleNode) t.getData()).render(context, writer);
}
catch( StopCommand stop )
{
if (!stop.isFor(this))
{
throw stop;
}
}
/*
* pass through application level runtime exceptions
*/
catch( RuntimeException e )
{
/*
* Log #parse errors so the user can track which file called which.
*/
log.error("Exception rendering #parse({}) at {}",
arg, StringUtils.formatFileString(this));
throw e;
}
catch ( Exception e )
{
String msg = "Exception rendering #parse(" + arg + ") at " +
StringUtils.formatFileString(this);
log.error(msg, e);
throw new VelocityException(msg, e, rsvc.getLogContext().getStackTrace());
}
finally
{
context.popCurrentTemplateName();
postRender(context);
}
/*
* note - a blocked input is still a successful operation as this is
* expected behavior.
*/
return true;
}
/**
* Called by the parser to validate the argument types
*/
@Override
public void checkArgs(ArrayList argtypes, Token t, String templateName)
throws ParseException
{
if (argtypes.size() != 1)
{
throw new MacroParseException("The #parse directive requires one argument",
templateName, t);
}
if (argtypes.get(0) == ParserTreeConstants.JJTWORD)
{
throw new MacroParseException("The argument to #parse is of the wrong type",
templateName, t);
}
}
}