Creating a Simple Xml File Using Python

Creating a simple XML file using python

These days, the most popular (and very simple) option is the ElementTree API,
which has been included in the standard library since Python 2.5.

The available options for that are:

ElementTree (Basic, pure-Python implementation of ElementTree. Part of the standard library since 2.5)
cElementTree (Optimized C implementation of ElementTree. Also offered in the standard library since 2.5. Deprecated and folded into the regular ElementTree as an automatic thing as of 3.3.)
LXML (Based on libxml2. Offers a rich superset of the ElementTree API as well XPath, CSS Selectors, and more)

Here's an example of how to generate your example document using the in-stdlib cElementTree:

import xml.etree.cElementTree as ET

root = ET.Element("root")
doc = ET.SubElement(root, "doc")

ET.SubElement(doc, "field1", name="blah").text = "some value1"
ET.SubElement(doc, "field2", name="asdfasd").text = "some vlaue2"

tree = ET.ElementTree(root)
tree.write("filename.xml")

I've tested it and it works, but I'm assuming whitespace isn't significant. If you need "prettyprint" indentation, let me know and I'll look up how to do that. (It may be an LXML-specific option. I don't use the stdlib implementation much)

For further reading, here are some useful links:

API docs for the implementation in the Python standard library
Introductory Tutorial (From the original author's site)
LXML etree tutorial. (With example code for loading the best available option from all major ElementTree implementations)

As a final note, either cElementTree or LXML should be fast enough for all your needs (both are optimized C code), but in the event you're in a situation where you need to squeeze out every last bit of performance, the benchmarks on the LXML site indicate that:

LXML clearly wins for serializing (generating) XML
As a side-effect of implementing proper parent traversal, LXML is a bit slower than cElementTree for parsing.

How to create XML file using Python?

You need to

Use ET.tostring() to get your xml as a string
Use xml.dom.minidom to get a DOM object from the string
Use toprettyxml() of DOM object to get the xml as formatted string
Add encoding information to the xml declaration part by simply splitting and concating the formatted string
Write the string to a file

Code:

import xml.etree.cElementTree as ET
import xml.dom.minidom

m_encoding = 'UTF-8'

root = ET.Element("data")
doc = ET.SubElement(root, "status", date="20210123")
ET.SubElement(doc, "name", name="john").text = "some value1"
ET.SubElement(doc, "class", name="abc").text = "some vlaue2"

dom = xml.dom.minidom.parseString(ET.tostring(root))
xml_string = dom.toprettyxml()
part1, part2 = xml_string.split('?>')

with open("FILE.xml", 'w') as xfile:
    xfile.write(part1 + 'encoding=\"{}\"?>\n'.format(m_encoding) + part2)
    xfile.close()

Output file

<?xml version="1.0" encoding="UTF-8"?>

<data>
    <status date="20210123">
        <name name="john">some value1</name>
        <class name="abc">some vlaue2</class>
    </status>
</data>

Best way to generate xml?

Using lxml:

from lxml import etree

# create XML 
root = etree.Element('root')
root.append(etree.Element('child'))
# another child with text
child = etree.Element('child')
child.text = 'some text'
root.append(child)

# pretty string
s = etree.tostring(root, pretty_print=True)
print s

Output:

<root>
  <child/>
  <child>some text</child>
</root>

See the tutorial for more information.

Python create XML file

You are on the right track save for a few minor syntax and usage issues:

class is a Python keyword, you can't use it as a function parameter name (which is essentially what class = 'playlistItem' is doing
data-type is not a valid variable name in Python, it will be evaluated as data MINUS type, consider using something like dataType or data_type. There might be ways around this but, IMHO, that would make the code unnecessarily complicated without adding any value (please see Edit #1 on how to do this)

That being said, the following code snippet should give you something usable and you can move on from there. Please feel free to let me know if you need any additional help:

from lxml import etree

data_el = etree.Element('data')

# You can do this in a loop and keep adding new elements
# Note: A deepcopy will be required for subsequent items
li_el = etree.SubElement(data_el, "li", class_name = 'playlistItem', data_type = "local", data_mp3 = "PATH")
a_el = etree.SubElement(li_el, "a", class_name = 'playlistNotSelected', href='#')

print etree.tostring(data_el, encoding='utf-8', xml_declaration = True, pretty_print = True)

This will generate the following output (which you can write to a file):

<?xml version='1.0' encoding='utf-8'?>
<data>
  <li class_name="playlistItem" data_mp3="PATH" data_type="local">
    <a class_name="playlistNotSelected" href="#"/>
  </li>
</data>

Edit #0:

Alternatively, you can also write to a file by converting it to an ElementTree first, e.g.

# Replace sys.stdout with a file object pointing to your object file:
etree.ElementTree(data_el).write(sys.stdout, encoding='utf-8', xml_declaration = True, pretty_print = True)

Edit #1:

Since element attributes are dictionaries, you can use set to specify arbitrary attributes without any restrictions, e.g.

li_el.set('class', 'playlistItem')
li_el.set('data-type', 'local')

generate a full XML file with python

Reference: http://lxml.de/tutorial.html#namespaces

You mustn't specify the namespace as a :-qualified string. Instead you may use {http://url.url/url}tag form, or QName form.

Here is your program, using namespaces:

from lxml import etree as ET

NS_DC = "http://purl.org/dc/elements/1.1/"
NS_OPF = "http://www.idpf.org/2007/opf"
nsmap = {
    "dc": NS_DC,
    None: NS_OPF,
}
PACKAGE = ET.QName(NS_OPF, 'package')
METADATA = ET.QName(NS_OPF, 'metadata')
TITLE = ET.QName(NS_DC, 'title')

et = ET.Element(PACKAGE,
                attrib={'version': "2.0",
                        'unique-identifier': "BookId"},
                nsmap=nsmap)

md = ET.SubElement(et, METADATA)
au = ET.SubElement(md, TITLE)
au.text = "A Tale of Two Cities"

s = ET.tostring(et, pretty_print=True)
print(s.decode('utf-8'))

You might choose to use lxml.builder.ElementMaker. Here is a program that creates a portion of your example.

Notes:

Note the use of dicts to represent attribute names that are not valid Python names.
Note the use of QName to represent namespace-qualified names.
Note the use of validator to validate the resulting tree.

from lxml import etree as ET
from lxml.builder import ElementMaker

NS_DC = "http://purl.org/dc/elements/1.1/"
NS_OPF = "http://www.idpf.org/2007/opf"
SCHEME = ET.QName(NS_OPF, 'scheme')
FILE_AS = ET.QName(NS_OPF, "file-as")
ROLE = ET.QName(NS_OPF, "role")
opf = ElementMaker(namespace=NS_OPF, nsmap={"opf": NS_OPF, "dc": NS_DC})
dc = ElementMaker(namespace=NS_DC)
validator = ET.RelaxNG(ET.parse("opf-schema.xml"))

tree = (
    opf.package(
        {"unique-identifier": "uuid_id", "version": "2.0"},
        opf.metadata(
            dc.identifier(
                {SCHEME: "uuid", "id": "uuid_id"},
                "d06a2234-67b4-40db-8f4a-136e52057101"),
            dc.creator({FILE_AS: "Homes, A. M.", ROLE: "aut"}, "A. M. Homes"),
            dc.title("My Book"),
            dc.language("en"),
        ),
        opf.manifest(
            opf.item({"id": "foo", "href": "foo.pdf", "media-type": "foo"})
        ),
        opf.spine(
            {"toc": "uuid_id"},
            opf.itemref({"idref": "uuid_id"}),
        ),
        opf.guide(
            opf.reference(
                {"href": "cover.jpg", "title": "Cover", "type": "cover"})
        ),
    )
)
validator.assertValid(tree)

print(ET.tostring(tree, pretty_print=True).decode('utf-8'))

Creating an XML file using Python

Use lxml.builder, here's a tutorial too.

   import lxml.builder as lb
   from lxml import etree

y=lb.E.Title(lb.E.s(name="hello",adress="abcdef"),
             lb.E.s(name="",adress=""),
             rollid="1", mainid="1",teamid="1")

print etree.tostring(y, pretty_print=True)

>>> 
<Title teamid="1" rollid="1" mainid="1">
  <s adress="abcdef" name="hello"/>
  <s adress="" name=""/>
</Title>

Python writing to an xml file

If you are wanting to replace a value within an existing XML file then use:

tree.write(xmlfile)

Currently you are simply overwriting your file entirely and using the incorrect method (open()). tree.write() is normally what you would want to use. It might look something like this:

tree = etree.parse(xmlfile, parser=XMLParser)
root = tree.getroot()
hardwareRevisionNode = root.find(".//hardwareRevision")
if hardwareRevisionNode.text == "5":
    print "Old Tag: " + hardwareRevisionNode.text
    hardwareRevisionNode.text = "DVT2"
    print "New Tag: " +  hardwareRevisionNode.text
    tree.write(xmlfile)

↳ https://docs.python.org/2/library/xml.etree.elementtree.html

Python generating xml file by python

Use this ElementTree. An example of it is,

from xml.etree import ElementTree, cElementTree
from xml.dom import minidom

root = ElementTree.Element('root')
child1 = ElementTree.SubElement(root, 'doc')
child1_1 = ElementTree.SubElement(child1, 'Jankyframes')
child1_1.text = jank_perc

print ElementTree.tostring(root)
tree = cElementTree.ElementTree(root) # wrap it in an ElementTree instance, and save as XML

t = minidom.parseString(ElementTree.tostring(root)).toprettyxml() # Since ElementTree write() has no pretty printing support, used minidom to beautify the xml.
tree1 = ElementTree.ElementTree(ElementTree.fromstring(t))

tree1.write("filename.xml",encoding='utf-8', xml_declaration=True)

Creating a Simple Xml File Using Python