Python xml ElementTree findall returns empty result - python

I would like to parse following XML file using the Python xml ElementTree API.
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<foos>
<foo_table>
<!-- bar -->
<fooelem>
<fname>BBBB</fname>
<group>SOMEGROUP</group>
<module>some module</module>
</fooelem>
<fooelem>
<fname>AAAA</fname>
<group>other group</group>
<module>other module</module>
</fooelem>
<!-- bar -->
</foo_table>
</foos>
In this example code I try to find all the elements under /foos/foo_table/fooelem/fname but obviously findall doesn't find anything when running this code.
import xml.etree.cElementTree as ET
tree = ET.ElementTree(file="min.xml")
for i in tree.findall("./foos/foo_table/fooelem/fname"):
print i
root = tree.getroot()
for i in root.findall("./foos/foo_table/fooelem/fname"):
print i
I am not experienced with the ElementTree API, but I've used the example under https://docs.python.org/2/library/xml.etree.elementtree.html#example. Why is it not working in my case?

foos is your root, you would need to start findall below, e.g.
root = tree.getroot()
for i in root.findall("foo_table/fooelem/fname"):
print i.text
Output:
BBBB
AAAA

This is because the path you are using begins BEFORE the root element (foos).
Use this instead: foo_table/fooelem/fname

findall doesn't work, but this does:
e = xml.etree.ElementTree.parse(myfile3).getroot()
mylist=list(e.iter('checksum'))
print (len(mylist))
mylist will have the proper length.

Related

xml parsing in python with XPath

I am trying to parse an XML file in Python with the built in xml module and Elemnt tree, but what ever I try to do according to the documentation, it does not give me what I need.
I am trying to extract all the value tags into a list
<?xml version="1.0" encoding="UTF-8"?>
<CustomField xmlns="http://soap.sforce.com/2006/04/metadata">
<fullName>testPicklist__c</fullName>
<externalId>false</externalId>
<label>testPicklist</label>
<required>false</required>
<trackFeedHistory>false</trackFeedHistory>
<type>Picklist</type>
<valueSet>
<restricted>true</restricted>
<valueSetDefinition>
<sorted>false</sorted>
<value>
<fullName>a 32</fullName>
<default>false</default>
<label>a 32</label>
</value>
<value>
<fullName>23 432;:</fullName>
<default>false</default>
<label>23 432;:</label>
</value>
and here is the example code that I cant get to work. It's very basic and all I have issues is the xpath.
from xml.etree.ElementTree import ElementTree
field_filepath= "./testPicklist__c.field-meta.xml"
mydoc = ElementTree()
mydoc.parse(field_filepath)
root = mydoc.getroot()
print(root.findall(".//value")
print(root.findall(".//*/value")
print(root.findall("./*/value")
Since the root element has attribute xmlns="http://soap.sforce.com/2006/04/metadata", every element in the document will belong to this namespace. So you're actually looking for {http://soap.sforce.com/2006/04/metadata}value elements.
To search all <value> elements in this document you have to specify the namespace argument in the findall() function
from xml.etree.ElementTree import ElementTree
field_filepath= "./testPicklist__c.field-meta.xml"
mydoc = ElementTree()
mydoc.parse(field_filepath)
root = mydoc.getroot()
# get the namespace of root
ns = root.tag.split('}')[0][1:]
# create a dictionary with the namespace
ns_d = {'my_ns': ns}
# get all the values
values = root.findall('.//my_ns:value', namespaces=ns_d)
# print the values
for value in values:
print(value)
Outputs:
<Element '{http://soap.sforce.com/2006/04/metadata}value' at 0x7fceea043ba0>
<Element '{http://soap.sforce.com/2006/04/metadata}value' at 0x7fceea043e20>
Alternatively you can just search for the {http://soap.sforce.com/2006/04/metadata}value
# get all the values
values = root.findall('.//{http://soap.sforce.com/2006/04/metadata}value')

python, xml: how to access the 3rd child by element' name

Would you help me, pleace, to get an access to elemnt with name 'id' by the following construction in Python (i have lxml and xml.etree.ElementTree libraries).
Desirable result: '0000000'
Desirable method:
Search in xml-document a child, where it's name is fcsProtocolEF3.
Search in fcsProtocolEF3 an element with name 'id'.
It is crucial to search by element name. Not by ordinal position.
I tried to use something like this: tree.findall('{http://zakupki.gov.ru/oos/export/1}fcsProtocolEF3')[0].findall('{http://zakupki.gov.ru/oos/types/1}id')[0].text
it works, but it requires to input namespaces. XML-document have different namespaces and I don't know how to define them beforehand.
Thank you.
That would be great to use something like XQuery in SQL:
value('(/*:export/*:fcsProtocolEF3/*:id)[1]', 'nvarchar(21)')) AS [id],
XML-document:
<?xml version="1.0" encoding="UTF-8" standalone="true"?>
<ns2:export xmlns:ns3="http://zakupki.gov.ru/oos/common/1" xmlns:ns4="http://zakupki.gov.ru/oos/base/1" xmlns:ns2="http://zakupki.gov.ru/oos/export/1" xmlns:ns10="http://zakupki.gov.ru/oos/printform/1" xmlns:ns11="http://zakupki.gov.ru/oos/control99/1" xmlns:ns9="http://zakupki.gov.ru/oos/SMTypes/1" xmlns:ns7="http://zakupki.gov.ru/oos/pprf615types/1" xmlns:ns8="http://zakupki.gov.ru/oos/EPtypes/1" xmlns:ns5="http://zakupki.gov.ru/oos/TPtypes/1" xmlns:ns6="http://zakupki.gov.ru/oos/CPtypes/1" xmlns="http://zakupki.gov.ru/oos/types/1">
<ns2:fcsProtocolEF3 schemeVersion="10.2">
<id>0000000</id>
<purchaseNumber>0000000000000000</purchaseNumber>
</ns2:fcsProtocolEF3>
</ns2:export>
lxml solution:
xml = '''<?xml version="1.0"?>
<ns2:export xmlns:ns3="http://zakupki.gov.ru/oos/common/1" xmlns:ns4="http://zakupki.gov.ru/oos/base/1" xmlns:ns2="http://zakupki.gov.ru/oos/export/1" xmlns:ns10="http://zakupki.gov.ru/oos/printform/1" xmlns:ns11="http://zakupki.gov.ru/oos/control99/1" xmlns:ns9="http://zakupki.gov.ru/oos/SMTypes/1" xmlns:ns7="http://zakupki.gov.ru/oos/pprf615types/1" xmlns:ns8="http://zakupki.gov.ru/oos/EPtypes/1" xmlns:ns5="http://zakupki.gov.ru/oos/TPtypes/1" xmlns:ns6="http://zakupki.gov.ru/oos/CPtypes/1" xmlns="http://zakupki.gov.ru/oos/types/1">
<ns2:fcsProtocolEF3 schemeVersion="10.2">
<id>0000000</id>
<purchaseNumber>0000000000000000</purchaseNumber>
</ns2:fcsProtocolEF3>
</ns2:export>'''
from lxml import etree as et
root = et.fromstring(xml)
text = root.xpath('//*[local-name()="export"]/*[local-name()="fcsProtocolEF3"]/*[local-name()="id"]/text()')[0]
print(text)
Below is ET based solution. NS are in use.
import xml.etree.ElementTree as ET
xml = '''<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ns2:export xmlns:ns3="http://zakupki.gov.ru/oos/common/1" xmlns:ns4="http://zakupki.gov.ru/oos/base/1" xmlns:ns2="http://zakupki.gov.ru/oos/export/1" xmlns:ns10="http://zakupki.gov.ru/oos/printform/1" xmlns:ns11="http://zakupki.gov.ru/oos/control99/1" xmlns:ns9="http://zakupki.gov.ru/oos/SMTypes/1" xmlns:ns7="http://zakupki.gov.ru/oos/pprf615types/1" xmlns:ns8="http://zakupki.gov.ru/oos/EPtypes/1" xmlns:ns5="http://zakupki.gov.ru/oos/TPtypes/1" xmlns:ns6="http://zakupki.gov.ru/oos/CPtypes/1" xmlns="http://zakupki.gov.ru/oos/types/1">
<ns2:fcsProtocolEF3 schemeVersion="10.2">
<id>0000000</id>
<purchaseNumber>0000000000000000</purchaseNumber>
</ns2:fcsProtocolEF3>
</ns2:export>
'''
def get_id_text():
root = ET.fromstring(xml)
fcs = root.find('{http://zakupki.gov.ru/oos/export/1}fcsProtocolEF3')
# assuming there is one fcs element and one id under fcs
return fcs.find('{http://zakupki.gov.ru/oos/types/1}id').text
print(get_id_text())
output
0000000

python ElementTree the text of element who has a child

When I try to read a text of a element who has a child, it gives None:
See the xml (say test.xml):
<?xml version="1.0"?>
<data>
<test><ref>MemoryRegion</ref> abcd</test>
</data>
and the python code that wants to read 'abcd':
import xml.etree.ElementTree as ET
tree = ET.parse('test.xml')
root = tree.getroot()
print root.find("test").text
When I run this python, it gives None, rather than abcd.
How can I read abcd under this condition?
Use Element.tail attribute:
>>> import xml.etree.ElementTree as ET
>>> tree = ET.parse('test.xml')
>>> root = tree.getroot()
>>> print root.find(".//ref").tail
abcd
ElementTree has a rather different view of XML that is more suited for nested data. .text is the data right after a start tag. .tail is the data right after an end tag. so you want:
print root.find('test/ref').tail

Programmatically clean/ignore namespaces in XML - python

I'm trying to write a simple program to read my financial XML files from GNUCash, and learn Python in the process.
The XML looks like this:
<?xml version="1.0" encoding="utf-8" ?>
<gnc-v2
xmlns:gnc="http://www.gnucash.org/XML/gnc"
xmlns:act="http://www.gnucash.org/XML/act"
xmlns:book="http://www.gnucash.org/XML/book"
{...}
xmlns:vendor="http://www.gnucash.org/XML/vendor">
<gnc:count-data cd:type="book">1</gnc:count-data>
<gnc:book version="2.0.0">
<book:id type="guid">91314601aa6afd17727c44657419974a</book:id>
<gnc:count-data cd:type="account">80</gnc:count-data>
<gnc:count-data cd:type="transaction">826</gnc:count-data>
<gnc:count-data cd:type="budget">1</gnc:count-data>
<gnc:commodity version="2.0.0">
<cmdty:space>ISO4217</cmdty:space>
<cmdty:id>BRL</cmdty:id>
<cmdty:get_quotes/>
<cmdty:quote_source>currency</cmdty:quote_source>
<cmdty:quote_tz/>
</gnc:commodity>
Right now, i'm able to iterate and get results using
import xml.etree.ElementTree as ET
r = ET.parse("file.xml").findall('.//')
after manually cleaning the namespaces, but I'm looking for a solution that could either read the entries regardless of their namespaces OR remove the namespaces before parsing.
Note that I'm a complete noob in python, and I've read: Python and GnuCash: Extract data from GnuCash files, Cleaning an XML file in Python before parsing and python: xml.etree.ElementTree, removing "namespaces" along with ElementTree docs and I'm still lost...
I've come up with this solution:
def strip_namespaces(self, tree):
nspOpen = re.compile("<\w*:", re.IGNORECASE)
nspClose = re.compile("<\/\w*:", re.IGNORECASE)
for i in tree:
start = re.sub(nspOpen, '<', tree.tag)
end = re.sub(nspOpen, '<\/', tree.tag)
# pprint(finaltree)
return
But I'm failing to apply it. I can't seem to be able to retrieve the tag names as they appear on the file.
I think below python code will be helpfull to you.
sample.xml
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<gnc:prodinfo xmlns:gnc="http://www.gnucash.org/XML/gnc"
xmlns:act="http://www.gnucash.org/XML/act"
xmlns:book="http://www.gnucash.org/XML/book"
xmlns:vendor="http://www.gnucash.org/XML/vendor">
<gnc:change>
<gnc:lastUpdate>2018-12-21
</gnc:lastUpdate>
</gnc:change>
<gnc:bill>
<gnc:billAccountNumber>1234</gnc:billAccountNumber>
<gnc:roles>
<gnc:id>111111</gnc:id>
<gnc:pos>2</gnc:pos>
<gnc:genid>15</gnc:genid>
</gnc:roles>
</gnc:bill>
<gnc:prodtyp>sales and service</gnc:prodtyp>
</gnc:prodinfo>
PYTHON CODE: to remove xmlns for root tag.
import xml.etree.cElementTree as ET
def xmlns(str):
str1 = str.split('{')
l=[]
for i in str1:
if '}' in i:
l.append(i.split('}')[1])
else:
l.append(i)
var = ''.join(l)
return var
tree=ET.parse('sample.xml')
root = tree.getroot()
print(root.tag) #returns root tag with xmlns as prefix
print(xmlns(root.tag)) #returns root tag with out xmlns as prefix
Output:
{http://www.gnucash.org/XML/gnc}prodinfo
prodinfo

Python and ElementTree: return "inner XML" excluding parent element

In Python 2.6 using ElementTree, what's a good way to fetch the XML (as a string) inside a particular element, like what you can do in HTML and javascript with innerHTML?
Here's a simplified sample of the XML node I am starting with:
<label attr="foo" attr2="bar">This is some text and a link in embedded HTML</label>
I'd like to end up with this string:
This is some text and a link in embedded HTML
I've tried iterating over the parent node and concatenating the tostring() of the children, but that gave me only the subnodes:
# returns only subnodes (e.g. and a link)
''.join([et.tostring(sub, encoding="utf-8") for sub in node])
I can hack up a solution using regular expressions, but was hoping there'd be something less hacky than this:
re.sub("</\w+?>\s*?$", "", re.sub("^\s*?<\w*?>", "", et.tostring(node, encoding="utf-8")))
How about:
from xml.etree import ElementTree as ET
xml = '<root>start here<child1>some text<sub1/>here</child1>and<child2>here as well<sub2/><sub3/></child2>end here</root>'
root = ET.fromstring(xml)
def content(tag):
return tag.text + ''.join(ET.tostring(e) for e in tag)
print content(root)
print content(root.find('child2'))
Resulting in:
start here<child1>some text<sub1 />here</child1>and<child2>here as well<sub2 /><sub3 /></child2>end here
here as well<sub2 /><sub3 />
This is based on the other solutions, but the other solutions did not work in my case (resulted in exceptions) and this one worked:
from xml.etree import Element, ElementTree
def inner_xml(element: Element):
return (element.text or '') + ''.join(ElementTree.tostring(e, 'unicode') for e in element)
Use it the same way as in Mark Tolonen's answer.
The following worked for me:
from xml.etree import ElementTree as etree
xml = '<root>start here<child1>some text<sub1/>here</child1>and<child2>here as well<sub2/><sub3/></child2>end here</root>'
dom = etree.XML(xml)
(dom.text or '') + ''.join(map(etree.tostring, dom)) + (dom.tail or '')
# 'start here<child1>some text<sub1 />here</child1>and<child2>here as well<sub2 /><sub3 /></child2>end here'
dom.text or '' is used to get the text at the start of the root element. If there is no text dom.text is None.
Note that the result is not a valid XML - a valid XML should have only one root element.
Have a look at the ElementTree docs about mixed content.
Using Python 2.6.5, Ubuntu 10.04

Categories

Resources