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PyAtom

PyAtom is a Python library module I wrote to make it very easy to create

an Atom syndication feed.

http://atomenabled.org/developers/syndication/

I have released PyAtom under The Academic Free License 2.1.  I intend to

donate PyAtom to the Python Software Foundation.

Notes on PyAtom:

XML is best represented in a tree structure, and PyAtom is a set of

classes that automatically manage the tree structure for the user.  The

top level of an Atom feed is an XML "Feed" element with a "<feed>" tag;

the Feed element has other elements nested inside it that describe the

feed, and then it has 0 or more Entry elements, each of which has

elements that describe the Entry.

Take a look at RunPyAtomTestCases(), at the end of pyatom.py, for

example code showing how to set up a feed with an entry.

To create an XML document with a feed in it, the user does this:

xmldoc = XMLDoc()

feed = Feed()

xmldoc.root_element = feed

To assign an entry to a feed, the user just does this:

feed.entries.append(entry)

This adds "entry" to the internal list that keeps track of entries.

"entry" is now nested inside "feed", which is nested inside "xmldoc".

Later, when the user wants to save the XML in a file, the user can just

do this:

f = open("file.xml", "w")

s = str(xmldoc)

f.write(s)

To make the string from xmldoc, the XMLDoc class walks through the XML

elements nested inside xmldoc, asking each one to return its string.

Each element that has other elements nested inside does the same thing.

The whole tree is recursively walked, and the tags all return strings

that are indented properly for their level in the tree.

The classes that implement Atom in PyAtom just use the heck out of

inheritance.  There are abstract base classes that implement broadly

useful behavior, and lots of classes that just inherit and use this

behavior; but there are plenty of places where the child classes

overload the inherited behavior and do something different.  The way

Python handles inheritance made this a joy to code up.

If you have any questions about anything here, please contact me using

this email address:

pyatom@langri.com