Quick Start

Python Support

This library supports these Python versions::

3.11

This library may be compatible with earlier versions of python as well.

Installation

Use pip to install this libary:

pip install lxml-util

Introduction

This is a python library providing the additional functionality to the lxml python library.

Limitations of lxml library:

When e is object of lxml.etree.Element

1. e.find() cannot handle prefixed tag names like “c:chart” and raises

   exceptions

2. e.findall() cannot handle prefixed tag names like “c:chart” and raises

   exceptions

3. e.makeelement() cannot handle prefixed tag names like “c:chart” and

   raises exceptions

4. e.get() cannot handle prefixed attribute names like “r:id” and raises

   exceptions

5. e.set() cannot handle prefixed attribute names like “r:id” and raises

   exceptions

6. e does not have direct access to its children through the attributes.

   e.chart gives attribute error though chart is child of element e

7. No handy method in e object to find the local name. Have to use

   etree.QName object to find the namespace of the element

8. No handy method in e object to find the namespace. Have to use

   etree.QName object to find the namespace of the element

9. No handy method in e object to get the fully Qualified Name from

   prefixed tag name

Advantages of lxml-util library:

All the above mentioned limitations are handled in this library

from lxmlutil.etree import ElementBase
from lxml import etree

fallback = etree.ElementDefaultClassLookup(ElementBase)
parser = etree.XMLParser()
parser.set_element_class_lookup(fallback)

e = etree.parse("path/to/xml/file", parser).getroot()

e.nsmap
#    {'c': 'http://schemas.openxmlformats.org/drawingml/2006/chart',
#     'a': 'http://schemas.openxmlformats.org/drawingml/2006/main',
#     'r': 'http://schemas.openxmlformats.org/officeDocument/2006/relationships',
#     'c16r2': 'http://schemas.microsoft.com/office/drawing/2015/06/chart'}

# Object e now has additional methods defined in lxmlutil.etree.ElementBase
# which are not available in lxml.etree.ElementBase

e.qn("c:chart") # "{http://schemas.openxmlformats.org/drawingml/2006/chart}chart"

e.ln            # "chartSpace"

e.ns            # "http://schemas.openxmlformats.org/drawingml/2006/chart"

e.find("c:chart")   # Gives error, cannot handle prefixed tag
e.findqn("c:chart") # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}chart at 0x189d739f520>

e.find("c:chart//c:areaChart") # Gives error, cannot handle prefixed tag
e.findqn("c:chart//c:areaChart") # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}areaChart at 0x189d739f700>

e.findall("c:chart//c:areaChart/c:axId") # Gives error, cannot handle prefixed tag
e.findallqn("c:chart//c:areaChart/c:axId") # [<Element {http://schemas.openxmlformats.org/drawingml/2006/chart}axId at 0x189d739f7a0>, <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}axId at 0x189d739f7f0>]

e.get('r:id') # Gives error, cannot handled prefixed attribute names
e.getqn('r:id') # resolves the prefixed name and gets the attribute

e.set('r:id', "rId4") # Gives error, cannot handle prefixed attribute names
e.setqn('r:id', "rId4") # resolves the prefixed name and sets the attribute

e.makeelement('c:graph') # Gives error, cannot handle prefixed tag names
e.meqn('c:graph') # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}graph at 0x189d739f7f0>

# Dynamic attributes:
e.c_chart               # equivalent to e.findqn('c:chart')
    # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}chart at 0x189d739f7f0>
    # c is prefix, chart is localname

e.c_chart__c_plotArea   # equivalent to e.findqn('c:chart/c:plotArea')
    # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}plotArea at 0x189d739f7a0>
    # Two underscores means './'

e.c_chart___c_areaChart # equivalent to e.findqn('c:chart//c:areaChart')
    # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}areaChart at 0x189d739f520>
    # Three underscores means './/'

e.c_externalData_r_id   # equivalent to e.findqn('c:externalData[@r:id]')
    # <Element {http://schemas.openxmlformats.org/drawingml/2006/chart}externalData at 0x189d739f8e0>
    # c is prefix for element tag
    # externalData is element localname
    # r is attribute prefix for element 'c:externalData'
    # id is attribute name for element  'c:externalData'

e.___mc_Choice          # equivalent to e.findqn('.//mc:Choice')
    # <Element {http://schemas.openxmlformats.org/markup-compatibility/2006}Choice at 0x189d739fd90>
    #Though mc is not in nsmap of e, this method tries to find what could
    #be the namespace of mc prefix based on nsmap of children of element e