[STR-1394] [upload] File upload maximum size validator

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.4.0
• Component/s: Core
• Environment: Operating System: All; Platform: All
• Bugzilla Id: 18981
• Assignee: Unassigned
• Reporter: Jerzy Puchala
• Created: 14/Apr/03 05:30
• Updated: 02/May/13 02:28

Description

There is a class which is checking if the size of uploaded file is not bigger
then allowed in validator.xml. Right now it exists as separate Validor class,
but the idea is to incorporate it into the Struts. In this version it works
checking both DynaForm and "static" forms. I was able to build DynaForm, wchich
contains fields org.apache.struts.upload.FormFile without the problem.

There is the code of the class with incorporated documentation:
<code>
/*

• Created on Apr 3, 2003
  *
  */
  package org.yourek.struts.validator;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.validator.Field;
import org.apache.commons.validator.ValidatorAction;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.upload.FormFile;
import org.apache.struts.validator.Resources;
import org.apache.commons.beanutils.DynaBean;

/**

• @author Jerzy Puchala
  *
  */
  public class FileSizeValidator {
  /**
• <p>Checks if the file uploaded from this field is smaller than value
  in var attribute.
• You can use pure Byte number in <var-value> or you may use B -
  for Bytes,
• KB - for Kiloytes, MB - for Megabytes and GB - for Gigabytes. (I
  hope you will not
• upload this way Terabytes)</p>
• To make this class work you have to:<br>
• 1. Add something simmilar to your validate.xml
• <pre>
  <validator name="maxfilesize"
  classname="org.yourek.struts.validate.FileSizeValidator"
  method="validateMaxFileSize"
  methodParams="java.lang.Object,

org.apache.commons.validator.ValidatorAction,
org.apache.commons.validator.Field,
org.apache.struts.action.ActionErrors,
javax.servlet.http.HttpServletRequest"
msg="errors.maxfilesize" />

<field property="smallPictFile" depends="maxfilesize">
<arg0 name="maxfilesize" key="${var:maxFileSize}"
resource="false" />
<var>
<var-name>maxFileSize</var-name>
<var-value>100KB</var-value>
</var>
</field>
</pre>

• <br>
• 2. Add to the validator-rules.xml as follow:<br>
• <pre>
  <validator name="maxfilesize"
  classname="org.yourek.struts.validator.FileSizeValidator"
  method="validateMaxFileSize"
  methodParams="java.lang.Object,

org.apache.commons.validator.ValidatorAction,
org.apache.commons.validator.Field,
org.apache.struts.action.ActionErrors,
javax.servlet.http.HttpServletRequest"
depends=""
msg="errors.maxfilesize">

<javascript><![CDATA[
function validateMaxFileSize(form)

{ return true; }

]]>
</javascript>
</validator>
</pre>

• @param bean The bean validation is being performed on.
• @param va The <code>ValidatorAction</code> that is currently being
  performed.
• @param field The <code>Field</code> object associated with the
  current field being validated.
• @param errors The <code>ActionErrors</code> object to add errors to
  if any validation errors occur.
• @param request Current request object.
• @return True if smaller or equall, false otherwise.
  */
  public static boolean validateMaxFileSize(
  Object bean,
  ValidatorAction va,
  Field field,
  ActionErrors errors,
  HttpServletRequest request) {

String fieldProperty = field.getProperty();

String maxFileSizeStr = field.getVarValue("maxFileSize");
int maxFileSize = 0;
if (maxFileSizeStr.charAt(maxFileSizeStr.length() - 1) == 'B') {
if (maxFileSizeStr.charAt(maxFileSizeStr.length() - 2)
== 'K')

{ maxFileSize = Integer.parseInt( maxFileSizeStr.substring( 0, maxFileSizeStr.length () - 2)) * 1024; }

else if (
maxFileSizeStr.charAt(maxFileSizeStr.length() -
2) == 'M')

{ maxFileSize = Integer.parseInt( maxFileSizeStr.substring( 0, maxFileSizeStr.length () - 2)) * 1048576; }

else if (
maxFileSizeStr.charAt(maxFileSizeStr.length() -
2) == 'G')

{ maxFileSize = Integer.parseInt( maxFileSizeStr.substring( 0, maxFileSizeStr.length () - 2)) * 1073741824; }

else

{ maxFileSize = Integer.parseInt( maxFileSizeStr.substring(0, maxFileSizeStr.length() - 1)); }

}
else

{ maxFileSize = Integer.parseInt(maxFileSizeStr); }

FormFile file = (FormFile) getProperty(bean, fieldProperty);

// check if (file != null) - there is no requirement that field
is required.
if (file != null && file.getFileSize() > maxFileSize)

{ errors.add( field.getKey(), Resources.getActionError(request, va, field)); return false; }

return true;
}

/**

• Return the property value from the page. It is naroving to have the
  ability to
• return only java.lang.String like in <a
  href="http://jakarta.apache.org/commons/beanutils/api/org/apache/commons/beanuti
  ls/BeanUtils.html#getProperty(java.lang.Object,%20java.lang.String)">

• http://jakarta.apache.org/commons/beanutils/api/org/apache/commons/beanutils/Bea
  nUtils.html#getProperty(java.lang.Object,%20java.lang.String)</a>

• To have flexibility of handling in DynaForm more classes and be able
  to validate the input
• we have to return java.lang.Object
• @param bean
• @param property
• @param application
• @return java.lang.Object
  */
  private static Object getProperty(Object bean, String property) {
  if (bean == null || property == null) { return null; }

Class beanClass = bean.getClass();
try {
if (bean instanceof DynaBean)

{ return ((DynaBean) bean).get(property); }

else

{ String methodName = new StringBuffer("get") .append(property.toUpperCase ().charAt(0)) .append(property.substring(1)) .toString(); Method method = beanClass.getMethod(methodName, null); return method.invoke(bean, null); }

}
catch (NoSuchMethodException e)

{ e.printStackTrace(); return null; }
catch (IllegalArgumentException e) { e.printStackTrace(); return null; }

catch (IllegalAccessException e)

{ e.printStackTrace(); return null; }
catch (InvocationTargetException e) { e.printStackTrace(); return null; }

}
}
</code>

Issue Links

• is depended upon by: STR-1705 Document how to use web.xml "maxFileSize" and how to deal with "MaxLengthExceededException"