1 files changed, 41 insertions, 0 deletions
diff --git a/docs/tutorials/lxmlgraph/step03/myapp/models.py b/docs/tutorials/lxmlgraph/step03/myapp/models.py
new file mode 100644
index 000000000..3c03de1a9
--- /dev/null
+++ b/docs/tutorials/lxmlgraph/step03/myapp/models.py
@@ -0,0 +1,41 @@
+from zope.interface import implements
+from zope.interface import Attribute
+from zope.interface import Interface
+from lxml import etree
+
+class IMyModel(Interface):
+    __name__ = Attribute('Name of the model instance')
+
+class BfgElement(etree.ElementBase):
+    """Handle access control and getitem behavior"""
+
+    implements(IMyModel)
+
+    @property
+    def __name__(self):
+        return self.xpath("@name")[0]
+
+    def __getitem__(self, child_name):
+        xp = "*[@name='%s']" % child_name
+        matches = self.xpath(xp)
+        if len(matches) == 0:
+            raise KeyError('No child found for %s' % child_name)
+        elif len(matches) > 1:
+            raise KeyError('More than one child for %s' % child_name)
+        else:
+            return matches[0]
+
+def get_root(environ):
+    # Setup the custom parser with our BfgElement behavior
+    parser_lookup = etree.ElementDefaultClassLookup(element=BfgElement)
+    parser = etree.XMLParser()
+    parser.set_element_class_lookup(parser_lookup)
+
+    # Now load the XML file
+    xmlstring = open("myapp/samplemodel.xml").read()
+    root = etree.XML(xmlstring, parser)
+
+    return root
+
+
+