keytree 0.2.1

Keytree provides several functions for manipulating KML using the ElementTree API. Elements can be adapted to the Python geo interface and then used with packages like Shapely:

>>> data = """<?xml version="1.0" encoding="UTF-8"?>
... <kml xmlns="http://www.opengis.net/kml/2.2">
...   <Document>
...     <Placemark>
...       <name>point</name>
...       <description>Point test</description>
...       <Point>
...         <coordinates>
...           -122.364383,37.824664,0
...         </coordinates>
...       </Point>
...     </Placemark>
...   </Document>
... </kml>
... """
>>> from xml.etree import ElementTree
>>> tree = ElementTree.fromstring(data)
>>> kmlns = tree.tag.split('}')[0][1:]
>>> placemarks = tree.findall('*/{%s}Placemark' % kmlns)
>>> p0 = placemarks[0]
>>> import keytree
>>> f = keytree.feature(p0)
>>> from shapely.geometry import asShape
>>> shape = asShape(f.geometry)
>>> shape.buffer(1.5).exterior.length
9.4209934708642571

Objects like those from geojson that provide the Python geo interface can also be converted to ElementTree API Elements:

>>> from geojson import Feature
>>> f = Feature('1',
...             geometry={
...                 'type': 'Point',
...                 'coordinates': (-122.364383, 37.824663999999999)
...                 },
...             title='Feature 1',
...             summary='The first feature',
...             content='Blah, blah, blah.'
...             )

A Shapely (or geojson) geometry could also be used in place of the dict:

>>> from shapely.geometry import Point
>>> f = Feature('1',
...             geometry=Point(-122.364383, 37.824664),
...             title='Feature 1',
...             summary='The first feature',
...             content='Blah, blah, blah.'
...             )

The first argument to the keytree.element function is an XML context, the created element will have the same namespace as that element:

>>> elem = keytree.element(tree, f)
>>> import pprint
>>> pprint.pprint((elem.tag, elem.text, list(elem)))
('{http://www.opengis.net/kml/2.2}Placemark',
 None,
 [<Element {http://www.opengis.net/kml/2.2}name at ...>,
  <Element {http://www.opengis.net/kml/2.2}Snippet at ...>,
  <Element {http://www.opengis.net/kml/2.2}description at ...>,
  <Element {http://www.opengis.net/kml/2.2}Point at ...>])
>>> pprint.pprint(list((e.tag, e.text, list(e)) for e in elem))
[('{http://www.opengis.net/kml/2.2}name', 'Feature 1', []),
 ('{http://www.opengis.net/kml/2.2}Snippet', 'The first feature', []),
 ('{http://www.opengis.net/kml/2.2}description', 'Blah, blah, blah.', []),
 ('{http://www.opengis.net/kml/2.2}Point',
  None,
  [<{http://www.opengis.net/kml/2.2}Element coordinates at ...>])]