RFC 2629            Writing I-Ds and RFCs using XML            June 1999


3. Processing the XML Source File

   This section concerns itself with applications that operate on an XML
   source file. A lot of XML tools are available, as are many lists of
   XML resources, e.g., Cafe con Leche [5].

   There are two kinds of XML tools: validating and non-validating.
   Both check that the source file conforms to the rules given in
   Section 2.1. However, in addition to making sure that the source file
   is well-formed, a validating tool also reads the DTD referenced by
   the source file to make sure that they match. There are a number of
   both validating and non-validating tools available.

3.1 Editing

   There are several XML editors available. Ideally, you want an editor
   that validates. This has two advantages:

   o  the editor provides guidance in fleshing-out the document
      structure; and,

   o  the editor validates that the source file matches the rules in the
      DTD.

   There are two major modes in Emacs that support XML: tdtd [6] and
   psgml [7]. The latter mode allows you to validate the source file (by
   calling an external program). If you visit the source file in Emacs
   and the major mode isn't "SGML" or "XML", then usually all it takes
   is adding these lines to your ".emacs" file:

       (setq auto-mode-alist
             (cons (cons "\\.xml$" 'sgml-mode) auto-mode-alist))

   and then restarting Emacs. If this doesn't work, try one of the
   sources above.

   The author uses both sgml-mode in Emacs, and a commercial validating
   editor, Clip! version 1.5 [8], when editing source files.

3.1.1 Checking

   If your editor doesn't validate, then you should run a program to
   validate the source file.

   The author uses the AlphaWorks XML parser [9] for this purpose. It
   requires that your system have a Java virtual machine. In addition to
   Java, there are validating parsers written in C, Perl, Python, and
   Tcl.




 
RFC 2629            Writing I-Ds and RFCs using XML            June 1999


3.2 Converting to Text Format

   The author has written the xml2rfc tool [10], which reads the source
   file and produces both a text and HTML version of the document.
   (This memo was produced using the xml2rfc tool.) Note that xml2rfc
   isn't a validating tool, so it's a good idea to use either a
   validating editor or run a stand-alone validating parser prior to
   using the tool.

3.3 Converting to HTML Format

   The XML Style Language (XSL) is used to describe transformations from
   the source file into some other structured file. So, ideally you
   should use an XSL-capable formatter to convert an XML source file to
   HTML.

   However, as of this writing XSL is still in considerable flux.
   (Hence, no reference was included in this memo, as by the time you
   read this section, the reference would be outdated.) So, in the
   interim, the author uses the xml2rfc tool for this purpose, even
   though this tool doesn't provide much flexibility in its HTML layout.

3.4 Viewing

   Browsers that support either XSL or Cascading Style Sheets (CSS) are
   able to view the source file directly.

   At present, the author doesn't use any of these browsers, instead
   converting source files to either text or HTML.