xmltodict
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Python module that makes working with XML feel like you are working with JSON
xmltodict
xmltodict
is a Python module that makes working with XML feel like you are working with JSON, as in this "spec":
>>> print(json.dumps(xmltodict.parse("""
... <mydocument has="an attribute">
... <and>
... <many>elements</many>
... <many>more elements</many>
... </and>
... <plus a="complex">
... element as well
... </plus>
... </mydocument>
... """), indent=4))
{
"mydocument": {
"@has": "an attribute",
"and": {
"many": [
"elements",
"more elements"
]
},
"plus": {
"@a": "complex",
"#text": "element as well"
}
}
}
Namespace support
By default, xmltodict
does no XML namespace processing (it just treats namespace declarations as regular node attributes), but passing process_namespaces=True
will make it expand namespaces for you:
>>> xml = """
... <root xmlns="http://defaultns.com/"
... xmlns:a="http://a.com/"
... xmlns:b="http://b.com/">
... <x>1</x>
... <a:y>2</a:y>
... <b:z>3</b:z>
... </root>
... """
>>> xmltodict.parse(xml, process_namespaces=True) == {
... 'http://defaultns.com/:root': {
... 'http://defaultns.com/:x': '1',
... 'http://a.com/:y': '2',
... 'http://b.com/:z': '3',
... }
... }
True
It also lets you collapse certain namespaces to shorthand prefixes, or skip them altogether:
>>> namespaces = {
... 'http://defaultns.com/': None, # skip this namespace
... 'http://a.com/': 'ns_a', # collapse "http://a.com/" -> "ns_a"
... }
>>> xmltodict.parse(xml, process_namespaces=True, namespaces=namespaces) == {
... 'root': {
... 'x': '1',
... 'ns_a:y': '2',
... 'http://b.com/:z': '3',
... },
... }
True
Streaming mode
xmltodict
is very fast (Expat-based) and has a streaming mode with a small memory footprint, suitable for big XML dumps like Discogs or Wikipedia:
>>> def handle_artist(_, artist):
... print(artist['name'])
... return True
>>>
>>> xmltodict.parse(GzipFile('discogs_artists.xml.gz'),
... item_depth=2, item_callback=handle_artist)
A Perfect Circle
Fantômas
King Crimson
Chris Potter
...
It can also be used from the command line to pipe objects to a script like this:
import sys, marshal
while True:
_, article = marshal.load(sys.stdin)
print(article['title'])
$ bunzip2 enwiki-pages-articles.xml.bz2 | xmltodict.py 2 | myscript.py
AccessibleComputing
Anarchism
AfghanistanHistory
AfghanistanGeography
AfghanistanPeople
AfghanistanCommunications
Autism
...
Or just cache the dicts so you don't have to parse that big XML file again. You do this only once:
$ bunzip2 enwiki-pages-articles.xml.bz2 | xmltodict.py 2 | gzip > enwiki.dicts.gz
And you reuse the dicts with every script that needs them:
$ gunzip enwiki.dicts.gz | script1.py
$ gunzip enwiki.dicts.gz | script2.py
...
Roundtripping
You can also convert in the other direction, using the unparse()
method:
>>> mydict = {
... 'response': {
... 'status': 'good',
... 'last_updated': '2014-02-16T23:10:12Z',
... }
... }
>>> print(unparse(mydict, pretty=True))
<?xml version="1.0" encoding="utf-8"?>
<response>
<status>good</status>
<last_updated>2014-02-16T23:10:12Z</last_updated>
</response>
Text values for nodes can be specified with the cdata_key
key in the python dict, while node properties can be specified with the attr_prefix
prefixed to the key name in the python dict. The default value for attr_prefix
is @
and the default value for cdata_key
is #text
.
>>> import xmltodict
>>>
>>> mydict = {
... 'text': {
... '@color':'red',
... '@stroke':'2',
... '#text':'This is a test'
... }
... }
>>> print(xmltodict.unparse(mydict, pretty=True))
<?xml version="1.0" encoding="utf-8"?>
<text stroke="2" color="red">This is a test</text>
Lists that are specified under a key in a dictionary use the key as a tag for each item. But if a list does have a parent key, for example if a list exists inside another list, it does not have a tag to use and the items are converted to a string as shown in the example below. To give tags to nested lists, use the expand_iter
keyword argument to provide a tag as demonstrated below. Note that using expand_iter
will break roundtripping.
>>> mydict = {
... "line": {
... "points": [
... [1, 5],
... [2, 6],
... ]
... }
... }
>>> print(xmltodict.unparse(mydict, pretty=True))
<?xml version="1.0" encoding="utf-8"?>
<line>
<points>[1, 5]</points>
<points>[2, 6]</points>
</line>
>>> print(xmltodict.unparse(mydict, pretty=True, expand_iter="coord"))
<?xml version="1.0" encoding="utf-8"?>
<line>
<points>
<coord>1</coord>
<coord>5</coord>
</points>
<points>
<coord>2</coord>
<coord>6</coord>
</points>
</line>
Ok, how do I get it?
Using pypi
You just need to
$ pip install xmltodict
Using conda
For installing xmltodict
using Anaconda/Miniconda (conda) from the
conda-forge channel all you need to do is:
$ conda install -c conda-forge xmltodict
RPM-based distro (Fedora, RHEL, …)
There is an official Fedora package for xmltodict.
$ sudo yum install python-xmltodict
Arch Linux
There is an official Arch Linux package for xmltodict.
$ sudo pacman -S python-xmltodict
Debian-based distro (Debian, Ubuntu, …)
There is an official Debian package for xmltodict.
$ sudo apt install python-xmltodict
FreeBSD
There is an official FreeBSD port for xmltodict.
$ pkg install py36-xmltodict
openSUSE/SLE (SLE 15, Leap 15, Tumbleweed)
There is an official openSUSE package for xmltodict.
# Python2
$ zypper in python2-xmltodict
# Python3
$ zypper in python3-xmltodict