Get attribute of first element using lxml - python

Trying to parse an XML file using lxml in Python, how do I simply get the value of an element's attribute? Example:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<item id="123">
<sub>ABC</sub>
</item>
I'd like to get the result 123, and store it as a variable.

When using etree.parse(), simply call .getroot() to get the root element; the .attrib attribute is a dictionary of all attributes, use that to get the value:
>>> from lxml import etree
>>> tree = etree.parse('test.xml')
>>> tree.getroot().attrib['id']
'123'
If you used etree.fromstring() the object returned is the root object already, so no .getroot() call is needed:
>>> tree = etree.fromstring('''\
... <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
... <item id="123">
... <sub>ABC</sub>
... </item>
... ''')
>>> tree.attrib['id']
'123'

Alternatively, you could use an XPath selector:
>>> from lxml import etree
>>> tree = etree.fromstring(b'''<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<item id="123">
<sub>ABC</sub>
</item>''')
>>> tree.xpath('/item/#id')
['123']

I think Martijn has answered your question. Building on his answer, you can also use the items() method to get a list of tuples with the attributes and values. This may be useful if you need the values of multiple attributes. Like so:
>>> from lxml import etree
>>> tree = etree.parse('test.xml')
>>> item = tree.xpath('/item')
>>> item.items()
[('id', '123')]
Or in case of string:
>>> tree = etree.fromstring("""\
... <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
... <item id="123">
... <sub>ABC</sub>
... </item>
... """)
>>> tree.items()
[('id', '123')]

Related

Get items from xml Python

I have an xml in python, need to obtain the elements of the "Items" tag in an iterable list.
I need get a iterable list from this XML, for example like it:
Item 1: Bicycle, value $250, iva_tax: 50.30
Item 2: Skateboard, value $120, iva_tax: 25.0
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<data>
<info>Listado de items</info>
<detalle>
<![CDATA[<?xml version="1.0" encoding="UTF-8"?>
<tienda id="tiendaProd" version="1.1.0">
<items>
<item>
<nombre>Bicycle</nombre>
<valor>250</valor>
<data>
<tax name="iva" value="50.30"></tax>
</data>
</item>
<item>
<nombre>Skateboard</nombre>
<valor>120</valor>
<data>
<tax name="iva" value="25.0"></tax>
</data>
</item>
<item>
<nombre>Motorcycle</nombre>
<valor>900</valor>
<data>
<tax name="iva" value="120.50"></tax>
</data>
</item>
</items>
</tienda>]]>
</detalle>
</data>
I am working with
import xml.etree.ElementTree as ET
for example
import xml.etree.ElementTree as ET
xml = ET.fromstring(stringBase64)
ite = xml.find('.//detalle').text
tixml = ET.fromstring(ite)
You can use BeautifulSoup4 (BS4) to do this.
from bs4 import BeautifulSoup
#Read XML file
with open("example.xml", "r") as f:
contents = f.readlines()
#Create Soup object
soup = BeautifulSoup(contents, 'xml')
#find all the item tags
item_tags = soup.find_all("item") #returns everything in the <item> tags
#find the nombre and valor tags within each item
results = {}
for item in item_tags:
num = item.find("nombre").text
val = item.find("valor").text
results[str(num)] = val
#Prints dictionary with key value pairs from the xml
print(results)

Parsing XML in Python with ElementTree

I'm using the documentation here to try to get only the values (name,ip , netmask) for certain elements.
This is an example of the structure of my xml:
<?xml version="1.0" ?>
<rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" xmlns:nc="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="urn:uuid:5cf32451-91af-4f71-a0bd-ead244b81b1f">
<data>
<interfaces xmlns="urn:ietf:params:xml:ns:yang:ietf-interfaces">
<interface>
<name>GigabitEthernet1</name>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">ianaift:ethernetCsmacd</type>
<enabled>true</enabled>
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>192.168.40.30</ip>
<netmask>255.255.255.0</netmask>
</address>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip"/>
</interface>
<interface>
<name>GigabitEthernet2</name>
<type xmlns:ianaift="urn:ietf:params:xml:ns:yang:iana-if-type">ianaift:ethernetCsmacd</type>
<enabled>true</enabled>
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<address>
<ip>10.10.10.1</ip>
<netmask>255.255.255.0</netmask>
</address>
</ipv4>
<ipv6 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip"/>
</interface>
</interfaces>
</data>
</rpc-reply>
Python code: This code returns nothing .
import xml.etree.ElementTree as ET
tree = ET.parse("C:\\Users\\Redha\\Documents\\test_network\\interface1234.xml")
root = tree.getroot()
namespaces = {'interfaces': 'urn:ietf:params:xml:ns:yang:ietf-interfaces' }
for elem in root.findall('.//interfaces:interfaces', namespaces):
s0 = elem.find('.//interfaces:name',namespaces)
name = s0.text
print(name)
interface = ET.parse('interface2.xml')
interface_root = interface.getroot()
for interface_attribute in interface_root[0][0]:
print(f"{interface_attribute[0].text}, {interface_attribute[3][0][0].text}, {interface_attribute[3][0][1].text}")

How to create a subset of document using lxml?

Suppose you have an lmxl.etree element with the contents like:
<root>
<element1>
<subelement1>blabla</subelement1>
</element1>
<element2>
<subelement2>blibli</sublement2>
</element2>
</root>
I can use find or xpath methods to get something an element rendering something like:
<element1>
<subelement1>blabla</subelement1>
</element1>
Is there a way simple to get:
<root>
<element1>
<subelement1>blabla</subelement1>
</element1>
</root>
i.e The element of interest plus all it's ancestors up to the document root?
I am not sure there is something built-in for it, but here is a terrible, "don't ever use it in real life" type of a workaround using the iterancestors() parent iterator:
from lxml import etree as ET
data = """<root>
<element1>
<subelement1>blabla</subelement1>
</element1>
<element2>
<subelement2>blibli</subelement2>
</element2>
</root>"""
root = ET.fromstring(data)
element = root.find(".//subelement1")
result = ET.tostring(element)
for node in element.iterancestors():
result = "<{name}>{text}</{name}>".format(name=node.tag, text=result)
print(ET.tostring(ET.fromstring(result), pretty_print=True))
Prints:
<root>
<element1>
<subelement1>blabla</subelement1>
</element1>
</root>
The following code removes elements that don't have any subelement1 descendants and are not named subelement1.
from lxml import etree
tree = etree.parse("input.xml") # First XML document in question
for elem in tree.iter():
if elem.xpath("not(.//subelement1)") and not(elem.tag == "subelement1"):
if elem.getparent() is not None:
elem.getparent().remove(elem)
print etree.tostring(tree)
Output:
<root>
<element1>
<subelement1>blabla</subelement1>
</element1>
</root>

Creating Dictionaries from XML Data in Python (with xml.etree.ElementTree)

I'm having similar difficulties to the one posed in this answered question, except the solution provided isn't working with my version of the problem.
With this sample XML data:
<?xml version="1.0" encoding="UTF-8"?>
<root>
<element>
<name>XYZ</name>
<value>789</value>
</element>
<element>
<name>ABC</name>
<value>123</value>
</element>
</root>
My goal is to obtain a dictionary with the keys XYZ,ABC and the corresponding values 789,123. In other words, it should output the same as:
dict(XYZ=789,ABC=123)
Find element tags, and their name, value children using findall and find methods:
>>> import xml.etree.ElementTree as ET
>>>
>>> root = ET.fromstring('''<?xml version="1.0" encoding="UTF-8"?>
... <root>
... <element>
... <name>XYZ</name>
... <value>789</value>
... </element>
... <element>
... <name>ABC</name>
... <value>123</value>
... </element>
... </root>
... ''')
>>> {e.find('name').text: e.find('value').text for e in root.findall('element')}
{'XYZ': '789', 'ABC': '123'}
Another try may be using xpath and lxml.etree.
from lxml import etree
s="""<root>
<element>
<name>XYZ</name>
<value>789</value>
</element>
<element>
<name>ABC</name>
<value>123</value>
</element>
</root>"""
tree = etree.fromstring(s)
data = [(i.xpath("./name//text()")[0],i.xpath("./value//text()")[0]) for i in tree.xpath("//element")]
print {k:v for k,v in data}
Output-
{'XYZ': '789', 'ABC': '123'}

Store XML values as Python list

I have XML stored as a string "vincontents", formatted as such:
<response>
<data>
<vin>1FT7X2B69CEC76666</vin>
</data>
<data>
<vin>1GNDT13S452225555</vin>
</data>
</response>
I'm trying to use Python's elementtree library to parse out the VIN values into an array or Python list. I'm only interested in the values, not the tags.
def parseVins():
content = etree.fromstring(vincontents)
vins = content.findall("data/vin")
print vins
Outputs all of the tag information:
[<Element 'vin' at 0x2d2eef0>, <Element 'vin' at 0x2d2efd0> ....
Any help would be appreciated. Thank you!
Use .text property:
>>> import xml.etree.ElementTree as etree
>>> data = """<response>
... <data>
... <vin>1FT7X2B69CEC76666</vin>
... </data>
... <data>
... <vin>1GNDT13S452225555</vin>
... </data>
... </response>"""
>>> tree = etree.fromstring(data)
>>> [el.text for el in tree.findall('.//data/vin')]
['1FT7X2B69CEC76666', '1GNDT13S452225555']

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