initial working env

greenbutton/utils.py

@@ -0,0 +1,28 @@
+#!/usr/bin/python
+
+ns = {'atom': 'http://www.w3.org/2005/Atom',
+      'espi': 'http://naesb.org/espi'}
+
+def getEntity(source, target, accessor=None, multiple=False):
+    """Extracts the named entity from the source XML tree.  `accessor` is a
+    function of one argyment; if provided and the target entity is found, the
+    target will be passed into `accessor` and its result will be returned.  If
+    `multiple` is true, the result will be all entities that match (i.e. the
+    function will use `finall` instead of `find`)."""
+    if multiple:
+        es = source.findall(target, ns)
+        if accessor:
+            return [ accessor(e) for e in es ]
+        else:
+            return es
+    else:
+        e = source.find(target, ns)
+        if e is not None and accessor is not None:
+            return accessor(e)
+        else:
+            return e
+
+def getLink(source, relation, multiple=False):
+    """Shorthand for pulling a link with the given "rel" attribute from the source."""
+    return getEntity(source, './atom:link[@rel="%s"]' % relation, lambda e: e.attrib['href'], multiple)
+