pyxser, Python XML Serialization

The pyxser name stands for Python XML Serialization and is a Python object to XML serializer and deserializer. In other words, it can convert a Python object into XML and also, convert that XML back into the original Python object. It uses a preorder traversal tree algorithm over the object tree and the XML tree. The algorithm is O(n), and uses some compiler construction techniques as memoization to create unique instances of each element in the object tree. It supports cross referenced and circular referenced object trees, so the serializer do not crash with those kinds of objects. Each serialized object before being deserialized is validated against the pyxser XML schema. It also uses mutually recursive functions to serialize and deserialize the object tree, but it has some features, like the depth argument, which allows you to stop serializing or deserializing the object tree at certain point. The pyxser module is self documented, if you want to take a look on the documentation, just run pydoc pyxser. The current version is 1.5.2-r2. It supports Python 2.4 to Python 2.7 and is available through easy_install.

A sample of a serialized object is the XML as follows:

<?xml version="1.0" encoding="utf-8"?>
<pyxs:obj xmlns:pyxs="http://projects.coder.cl/pyxser/model/"
          version="1.0"
          type="TestAnotherObject"
          module="testpkg.sample"
          id="id-136688140">
  <pyxs:prop type="str" name="first_element">456</pyxs:prop>
  <pyxs:prop type="str" name="second_element">789</pyxs:prop>
</pyxs:obj>

This project pyxser supports cross referenced objects and nested referenced object, because it defines the a ref attribute as IDREF which is used to link internal nodes in the document tree.

• Serialization of cross references.
• Serialization of circular references.
• Preserves object references.
• Custom serializations.
• Custom deserializations.
• Custom serialization depth limit.
• Object attribute selection callback.
• Standards based serialization.
• Standards based XML validation using pyxser XML Schema.
• C14N based serialization, as optional kind of output.
• Model based XML serialization, represented on XML Schema and XML DTD.

You should see the INSTALLING file to see installing instructions. Also you can install it using pip:

pip install pyxser
pydoc pyxser

Or easy_install if you want:

easy_install pyxser
pydoc pyxser

Once you have installed pyxser, you can start serializing objects using code similar to this:

import pyxser as pyx

class TestClass(object):
    a = None
    b = None
    c = None

    def __init__(self, a, b, c):
        self.a = a
        self.b = b
        self.c = c

tst = TestClass("var_a", "var_b", "var_c")
ser = pyx.serialize(obj=tst, enc="utf-8")
print(ser)

This will give you an output similar to this one:

<?xml version="1.0" encoding="utf-8"?>
<pyxs:obj xmlns:pyxs="http://projects.coder.cl/pyxser/model/" version="1.0" type="TestClass" module="__main__" objid="id3074097420">
  <pyxs:prop type="str" name="a">var_a</pyxs:prop>
  <pyxs:prop type="str" name="c">var_c</pyxs:prop>
  <pyxs:prop type="str" name="b">var_b</pyxs:prop>
</pyxs:obj>

Related Webpages

The pyxser main web page is located here coder.cl

Authors

• Copyright (c) 2009 Daniel Molina Wegener coder.cl