pyfo

Easily generate XML from Python data structures.

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This package was developed by Luke Arno for Central Piedmont Community College in response to dissatisfaction with available alternatives for quickly generating XML. Concatenating strings is ugly and error-prone, using OO APIs for XML is heavy and overkill for generating simple XML output.

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The lastest version is available via pyfo's Cheese Shop Page.

Tutorial

pyfo provides a method called pyfo. I should not have named them both the same but I did. The signature looks like this: 


pyfo(node, prolog=False, pretty=False, indent_size=2, encoding='utf-8')

Node can be any number of things. Most often it will be a tuple shaped like this: 


('elementname', node_or_child_nodes, {'attr':'value'})

The dict of attributes is optional: 


('elementname', node_or_child_nodes)

node can also be most any other type and should usually do what you might expect.

One good example is worth a hundred pages of description. So lets take some data that you need to turn into xml: 


test_input = \
('root',
 [('string','hello'),
  ('float', 3.14),
  ('int', 5),
  ('unicode', u'this is unicode: \u221e'),
  ('list', [('node', 'hello'), '<raw-node message="hello"/>']),
  ('dictionary', dict(parrot='dead', spam='eggs')),
  ('generator', (('node', x) for x in range(6))),
  ('tuple', ('one', 'two')),
  ('None', None),
  ('int-zero', 0),
  ('float-zero', 0.0),
  ('empty-string', ""),
  ('object', type('obj', (), dict(__repr__=lambda s: "object repr"))()),
  ('func', lambda: 'this is a func'),
  ('escaping', ' > < & ')])

pyfo returns a unicode object so if you are going to output to an ascii terminal you should do something like this: 


from pyfo import pyfo
result = pyfo(test_input, pretty=True, prolog=True, encoding='ascii')
print result.encode('ascii', 'xmlcharrefreplace')

You could try to print the result directly if you are using all ascii characters but that is usually a pretty bad assumptions to make.

Your output should look like this: 


<?xml version="1.0" encoding="ascii"?>
<root>
  <string>hello</string>
  <float>3.14</float>
  <int>5</int>
  <unicode>this is unicode: &#8734;</unicode>
  <list>
    <node>hello</node>
    <raw-node message="hello"/>
  </list>
  <dictionary>
    <parrot>dead</parrot>
    <spam>eggs</spam>
  </dictionary>
  <generator>
    <node>0</node>
    <node>1</node>
    <node>2</node>
    <node>3</node>
    <node>4</node>
    <node>5</node>
  </generator>
  <tuple>
    <one>two</one>
  </tuple>
  <None/>
  <int-zero>0</int-zero>
  <float-zero>0.0</float-zero>
  <empty-string/>
  <object>object repr</object>
  <func>this is a func</func>
  <escaping> &gt; &lt; &amp; </escaping>
</root>

Questions, comments, suggestions, bugs... :