XSL based XML Parser

IBM Tivoli Directory Integrator

The XSL based XML DOM Parser enables TDI to parse XML documents in any format using the XSL supplied by the user, into attribute value pairs, stored in the entry object. The XSL based parser is required to facilitate reading of any kind of XML format. Particularly, when the user needs only a specific chunk of the XML he can write an XSL for picking the required chunk. The parser will create an in-memory parse tree to represent the input XML and the TDI internal format. The XSL transforms the DOM Document generated from input XML, and produces an output DOM for the TDI internal format. It uses the javax transformation libraries to carry out transformations.

Configuration

The XSL based DOM XML Parser provides the following parameters:

Use input XSL file: Check box to indicate whether to use input XSL file or use the XSL keyed in (in the Input XSL field)
Input XSL File Name: The input XSL file that contains template matching rules for transforming user XML to TDI internal format
Input XSL: Editable area to allow the user to key in or paste the entire input XSL.
Use output XSL file: Check box to indicate whether to use output XSL file or use the XSL keyed in (in the Output XSL field).
Output XSL File Name: The output XSL file that has template matching rules for transforming TDI internal format back to user XML
Output XSL: Editable area to allow the user to key in or paste the entire output XSL.
Character Encoding: The character encoding to use when reading or writing; the default is UTF-8.
This Parser extends the Simple XML Parser; therefore, the same notices with regards to Character Encoding apply.
Omit XML Declaration: If checked, omit XML declaration header in output stream.
Document validation: if checked, request a DTD/XSchema validating XML parser.
Namespace aware: If checked, request a namespace aware XML parser.
Indent Output: If checked, causes the output to be neatly indented, improving human readability. If the output is going to be processed by another program, this option is best left off.
Detailed log: Specifies whether detailed debug information is written to the log.

Using the Parser

The parser can be used with the Filesystem Connector in Iterator or AddOnly mode. The XSL based DOM XML parser requires the user to specify:

The input XSL file (when used in a Filesystem Connector in Iterator mode): to transform XML to TDI internal format.
The output XSL file (when used in a Filesystem connector in AddOnly mode): to transform TDI internal format back to the original format.

In an XSL transformation, an XSLT processor reads both an XML document and an XSLT style sheet. Based on the instructions the processor finds in the XSLT style sheet, it outputs a new XML document or fragment thereof. The parser will do the basic validation of the XSL files for authenticity. The parser also has optional Document and namespace validation of the file supplied by the Connector. The parser can be used in conjunction with the filesystem connector. The parser will support reading as well as writing, in the sense that XML files can be read and written to in a format specified by the respective XSL. The following optional validations are provided:

Document validation
Namespace aware

TDI Internal Format

<DocRoot>
  <Entry>
    <attribute_name> 
      <value_tag>attribute_value</value_tag>
      <value_tag>attribute_value</value_tag>
      <value_tag>attribute_value</value_tag>
    </ attribute_name>
    <attribute_name> 
      <value_tag>attribute_value</value_tag>
    </ attribute_name>
          -
          -
          -
  </Entry>
  <Entry>
          -
          -
          -
  </Entry>
  -
</DocRoot>

Example

Input XML: birds.XML

<?XML version="1.0" encoding="UTF-8"?>
<Class>
<Order Name="TINAMIFORMES">         <Family Name="TINAMIDAE">             <Species Scientific_Name="Tinamus major">  Great Tinamou.</Species>
            <Species Scientific_Name="Nothocercus">Highland Tinamou.</Species>
            <Species Scientific_Name="Crypturellus soui">Little Tinamou.</Species>
            <Species Scientific_Name="Crypturellus cinnamomeus">Thicket Tinamou.</Species>
            <Species Scientific_Name="Crypturellus boucardi">Slaty-breasted Tinamou.</Species>
            <Species Scientific_Name="Crypturellus kerriae">Choco Tinamou.</Species>
        </Family>
    </Order>
<Order Name="GAVIIFORMES">         <Family Name="GAVIIDAE">             <Species Scientific_Name="Gavia stellata">Red-throated Loon.</Species>
            <Species Scientific_Name="Gavia arctica">Arctic Loon.</Species>
            <Species Scientific_Name="Gavia pacifica">Pacific Loon.</Species>
            <Species Scientific_Name="Gavia immer">Common Loon.</Species>
            <Species Scientific_Name="Gavia adamsii">Yellow-billed Loon.</Species>
        </Family>
    </Order>
</Class>

Input XSL: birds.XSL

<?XML version="1.0" ?> 
<XSL:stylesheet xmlns:XSL="http://www.w3.org/1999/XSL/Transform" version="1.0">   <XSL:output method="XML" indent="yes" /> 
<XSL:template match="Class">  <DocRoot>
  <XSL:for-each select="Order">      <XSL:variable name="order"><XSL:value-of select="@Name" /> 
     </XSL:variable> 
     <XSL:for-each select="Family">       <Entry>
        <Attribute name="Order">       <Value><XSL:value-of select="$order" /></Value> 
    </Attribute>
       < Attribute name="Family">       <Value><XSL:value-of select="@Name" /></Value> 
       </Attribute>
       <Attribute name="Species">         <XSL:for-each select="Species">                 <Value><XSL:value-of select="." /></Value> 
        </XSL:for-each>
       </Attribute>
      </Entry>
   </XSL:for-each>
    </XSL:for-each>
 </DocRoot>
</XSL:template>
</XSL:stylesheet>

birds.xsl transforms birds.xml to TDI internal format from entry object with attribute value pairs, can be formed.