Added a better XML library.

git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@558742 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 250 insertions, 0 deletions

diff --git a/python/mllib/dom.py b/python/mllib/dom.py
new file mode 100644
index 0000000000..9b1740055b
--- /dev/null
+++ b/python/mllib/dom.py
@@ -0,0 +1,250 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+# 
+#   http://www.apache.org/licenses/LICENSE-2.0
+# 
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+"""
+Simple DOM for both SGML and XML documents.
+"""
+
+from transforms import Text
+
+class Container:
+
+  def __init__(self):
+    self.children = []
+
+  def add(self, child):
+    child.parent = self
+    self.children.append(child)
+
+  def extend(self, children):
+    for child in children:
+      child.parent = self
+      self.children.append(child)
+
+class Component:
+
+  def __init__(self):
+    self.parent = None
+
+  def index(self):
+    if self.parent:
+      return self.parent.children.index(self)
+    else:
+      return 0
+
+  def _line(self, file, line, column):
+    self.file = file
+    self.line = line
+    self.column = column
+
+class DispatchError(Exception):
+
+  def __init__(self, scope, f):
+    msg = "no such attribtue"
+
+class Dispatcher:
+
+  def is_type(self, type):
+    cls = self
+    while cls != None:
+      if cls.type == type:
+        return True
+      cls = cls.base
+    return False
+
+  def dispatch(self, f):
+    cls = self
+    while cls != None:
+      if hasattr(f, cls.type):
+        return getattr(f, cls.type)(self)
+      else:
+        cls = cls.base
+
+    cls = self
+    attrs = ""
+    while cls != None:
+      if attrs:
+        sep = ", "
+        if cls.base == None:
+          sep += "or "
+      else:
+        sep = ""
+      attrs += "%s'%s'" % (sep, cls.type)
+      cls = cls.base
+
+    raise AttributeError("'%s' object has no attribute %s" %
+                         (f.__class__.__name__, attrs))
+
+class Node(Container, Component, Dispatcher):
+
+  type = "node"
+  base = None
+
+  def __init__(self):
+    Container.__init__(self)
+    Component.__init__(self)
+    self.query = Query([self])
+
+  def __getitem__(self, name):
+    for nd in self.query[name]:
+      return nd
+
+  def text(self):
+    return self.dispatch(Text())
+
+  def tag(self, name, *attrs, **kwargs):
+    t = Tag(name, *attrs, **kwargs)
+    self.add(t)
+    return t
+
+  def data(self, s):
+    d = Data(s)
+    self.add(d)
+    return d
+
+  def entity(self, s):
+    e = Entity(s)
+    self.add(e)
+    return e
+
+class Tree(Node):
+
+  type = "tree"
+  base = Node
+
+class Tag(Node):
+
+  type = "tag"
+  base = Node
+
+  def __init__(self, _name, *attrs, **kwargs):
+    Node.__init__(self)
+    self.name = _name
+    self.attrs = list(attrs)
+    self.attrs.extend(kwargs.items())
+    self.singleton = False
+
+  def get_attr(self, name):
+    for k, v in self.attrs:
+      if name == k:
+        return v
+
+  def __getitem__(self, name):
+    if name and name[0] == "@":
+      return self.get_attr(name[1:])
+    else:
+      for nd in self.query[name]:
+        return nd
+      return self.get_attr(name)
+
+  def dispatch(self, f):
+    try:
+      method = getattr(f, "do_" + self.name)
+    except AttributeError:
+      return Dispatcher.dispatch(self, f)
+    return method(self)
+
+class Leaf(Component, Dispatcher):
+
+  type = "leaf"
+  base = None
+
+  def __init__(self, data):
+    assert isinstance(data, basestring)
+    self.data = data
+
+class Data(Leaf):
+  type = "data"
+  base = Leaf
+
+class Entity(Leaf):
+  type = "entity"
+  base = Leaf
+
+class Character(Leaf):
+  type = "character"
+  base = Leaf
+
+class Comment(Leaf):
+  type = "comment"
+  base = Leaf
+
+###################
+## Query Classes ##
+###########################################################################
+
+class View:
+
+  def __init__(self, source):
+    self.source = source
+
+class Filter(View):
+
+  def __init__(self, predicate, source):
+    View.__init__(self, source)
+    if callable(predicate):
+      self.predicate = predicate
+    elif predicate[0] == "#":
+      type = predicate[1:]
+      self.predicate = lambda x: x.is_type(type)
+    else:
+      self.predicate = lambda x: isinstance(x, Tag) and x.name == predicate
+
+  def __iter__(self):
+    for nd in self.source:
+      if self.predicate(nd): yield nd
+
+class Flatten(View):
+
+  def __iter__(self):
+    sources = [iter(self.source)]
+    while sources:
+      try:
+        nd = sources[-1].next()
+        if isinstance(nd, Tree):
+          sources.append(iter(nd.children))
+        else:
+          yield nd
+      except StopIteration:
+        sources.pop()
+
+class Children(View):
+
+  def __iter__(self):
+    for nd in self.source:
+      for child in nd.children:
+        yield child
+
+class Query(View):
+
+  def __iter__(self):
+    for nd in self.source:
+      yield nd
+
+  def __getitem__(self, predicate):
+    if isinstance(predicate, basestring):
+      path = predicate.split("/")
+    else:
+      path = [predicate]
+
+    query = self.source
+    for p in path:
+      query = Query(Filter(p, Flatten(Children(query))))
+
+    return query