ATOM V1 -> RSS V2

The project produces RSS2 file from Atom file. It provides an XSL stylesheet (V2) for this purpose.

Informations and validator about Atom format : validator.w3.org for Atom

Informations and validator about RSS2 format : validator.w3.org for RSS2

XSL stylesheet

Assumptions for the XSL transformation (with an XSLT 2 processor):

• Atom feed is valid without warning
• RSS2 feed will be valid without warning
• Atom feed is named feedname.xml
• RSS2 feed will be named feedname.rss2 (only the extension is changed in the self link inside the content)
• Use XSLT v2 to format date RFC 822

Python

The small component xslt_ext.py takes the XSLT v2 stylesheet and makes some tweaks. The lxml package only supports XSLT v1 transformations.

Then the call to the XSLT 2 function format-dateTime isn't possible.

As a result, the component :

• defines 1 new XSL that imports the original (XSL v2) and produce an XSL v1 stylesheet
• defines a python extension to convert the dates from ISO format (used in Atom) to RFC 822 format (used in RSS2)
• replaces the XSL template calling format-dateTime by an XSL template calling python function
• makes the transformation in XSLT 1

Code to makes the XSL transformation in python :

proc = xslt_ext.DateFormatterProcessor()
proc.load_xslt(xslt_filename) # defaut=atom1_to_rss2_pyext.xsl
result_xml = proc.transform(etree.parse(atom_filename))

Program to convert atom feed into rss feed : atom1_to_rss2.py

$ python atom1_to_rss2.py --help

usage: atom1_to_rss2.py [-h] [--atom ATOM] [--rss2 RSS2] [--xslt XSLT]

optional arguments:
  -h, --help   show this help message and exit
  --atom ATOM  Atom filename (input)
  --rss2 RSS2  RSS2 filename (output)
  --xslt XSLT  XSLT stylesheet (optionnal), default=atom1_to_rss2_pyext.xsl

Licence

MIT