Python ElementTree Serialize Error when writing to disk

Question

I parse a file in python

tree = ET.parse('existing.xml')

Add some xml Elements in memory into the XML Structure

NodeList = tree.findall(".//NodeList")

NodeList_WeWant = buildingNodeList[0]

for member in aList:
    ET.SubElement(NodeList_WeWant,member)

Write back to Disk

tree.write("output.sbp", encoding="utf-16")

But I get

Traceback (most recent call last):
  File "runonreal.py", line 156, in <module>
    tree.write("output.sbp", encoding="utf-16")
  File "C:\Python340\lib\xml\etree\ElementTree.py", line 775, in write
    qnames, namespaces = _namespaces(self._root, default_namespace)
  File "C:\Python340\lib\xml\etree\ElementTree.py", line 887, in _namespaces
    _raise_serialization_error(tag)
  File "C:\Python340\lib\xml\etree\ElementTree.py", line 1059, in _raise_serialization_error
    "cannot serialize %r (type %s)" % (text, type(text).__name__)
TypeError: cannot serialize <Element 'BuildingNodeBase' at 0x099421B0> (type Element)

Edit. A Simple Replication of Error. See Below

My basic xml

<?xml version="1.0" encoding="UTF-8"?>
<family>
  <person>
  <id>100</id>
  <name>Shorn</name>
  <height>5.8</height>
  </person>
  <person>
  <id>101</id>
  </person>
</family>

Python Script

import xml.etree.ElementTree as ET
from copy import deepcopy

tree = ET.parse('basic.xml')

root = tree.getroot()

cloneFrom = tree.findall(".//person[name='Shorn']")

cloneTo =  tree.findall(".//person[id='101']")

cloneTo = deepcopy(cloneFrom)

ET.SubElement(root,cloneTo)

tree.write("output.xml", encoding="utf-16")

This errors out

And this is my expected output.xml . Person Node should be cloned to another person node and written back to disk.

<?xml version="1.0" encoding="UTF-16"?>
<family>
  <person>
  <id>100</id>
  <name>Shorn</name>
  <height>5.8</height>
  </person>
  <person>
  <id>100</id>
  <name>Shorn</name>
  <height>5.8</height>
  </person>
</family>

mzjn · Accepted Answer · 2017-05-17 10:51:17Z

There are some problems here:

findall() returns a list, not a single element.
SubElement expects a string, not an Element object, as the second argument.
The element with id='101' is not removed.

Here is code that works for me (tested with Python 3.6.1):

import xml.etree.ElementTree as ET
from copy import deepcopy

tree = ET.parse('basic.xml')
root = tree.getroot()

remove = tree.find(".//person[id='101']")
cloneFrom = tree.find(".//person[name='Shorn']")

root.remove(remove)
root.append(deepcopy(cloneFrom))

tree.write("output.xml", encoding="utf-16")

This is what output.xml looks like:

<?xml version='1.0' encoding='utf-16'?>
<family>
  <person>
    <id>100</id>
    <name>Shorn</name>
    <height>5.8</height>
  </person>
  <person>
    <id>100</id>
    <name>Shorn</name>
    <height>5.8</height>
  </person>
  </family>

Collectives™ on Stack Overflow

Python ElementTree Serialize Error when writing to disk

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related