Hello,

 

I've been looking at modeling Rich Text Format (RTF) files using the IBM Message Broker DFDL implementation, and ran into an issue. For some background, here's a small example of an RTF file:

 

{\rtf1\ansi\ansicpg1252\deff0\deflang1033{\fonttbl{\f0\froman\fprq2\fcharset0 Times New Roman;}{\f1\fswiss\fcharset0 Arial;}}{\*\generator Msftedit 5.41.15.1515;}\viewkind4\uc1\pard\f0\fs24 This is an example document of an RTF file.\f1\fs20\par{\*\passwordhash 010000004c000000010000000480000050c300001400000010000000f89c360d0c9d360d000000008bc29e2f78a2144122ed68a1701e2ea50bbbbeaf7333c40dfe048ccf55f709b8cc7e8b49}}

 

'\' and '\*\' mark the beginning of control words, and the curly braces mark the beginning and end of control groups that contain control words and data. My issue is that control words and data do not have suitable terminators for parsing. The end of control words is signified by a space when trailing data is present, but typically they are ended by '\' signalling the beginning of a new word or a curly brace signalling the end of the current of beginning of a new control group. Similarly data is typically ended by the '}' of the parent control group.

 

With the exception of a small header the value and placement of control words, groups, and data varies by file.

 

My issue with modeling this is that I was going to use dfdl:lengthKind="pattern" in lieu of suitable delimiters, but this feature is not implemented by IBM. I'm looking for an alternative way to model the data, and was hoping someone on the mailing list might have suggestions. My goal is to model control words and groups in as general a manner as possible given IBMs implementation restrictions, since RTF has over 1800 defined control words and gives you the ability to create your own.

 

Ideal output for the above sample would be something along these lines:

 

<file>

   <controlWord>rtf1</controlWord>

   <controlWord>ansi</controlWord>

   <controlWord>ansicpg1252</controlWord>

   <controlWord>deff0</controlWord>

   <controlWord>deflang1033</controlWord>

   <controlGroup>

       <name>fonttbl</name>

       <controlGroup>

           <name>f0</name>

           <controlWord>froman</controlWord>

       </controlGroup>

       <controlGroup>

           <name>f1</name>

           <data>Arial;</data>

       </controlGroup>

   </controlGroup>

   <controlGroup>

       <name>generator</name>

       <data>Msftedit 5.41.15.1515;</data>

   </controlGroup>

   <controlWord>viewkind4</controlWord>

   <controlWord>uc1</controlWord>

   <controlWord>pard</controlWord>

   <controlWord>f0</controlWord>

   <controlWord>fs24</controlWord>

   <text>This is an example document of an RTF file.</text>

   <controlWord>f1</controlWord>

   <controlWord>fs20</controlWord>

   <controlWord>par</controlWord>

   <controlGroup>

       <name>passwordhash</name>

       <data>010000004c000000010000000480000050c3. . .</data>

   </controlGroup>

</file>

 

IBM Unsupported Features:

 

I know that's a lot of info out of left field, but I wanted to try and explain it as thoroughly as possible to avoid any confusion. Thanks in advance for any advice you might have and let me know if I've been unclear in any areas.

 

Bradley Sexton