Parse XML file from unit test Python

Question

I'm trying to write some unit tests with certain methods that parse different elements of my XML. But I'm having a few issues parsing a "test" xml file in my unit test.

My question isn't so much about anything to do with the XML/XSD files, but it's just around how to parse them correctly in my unit test.

This is my code so far:

import unittest
from lxml import etree
from Directory.method_in_class import ClassName #changed the names for security

class TestXmlData(unittest.TestCase):
    def setUp(self):
        self.method_in_class = ClassName()
        XSDDoc = etree.parse("dir/testxsd.xsd")
        rootXSD = XSDDoc.getroot()

    def test_whatever(self):
        # Test whatever

if __name__ == '__main__':
    unittest.main()

Even though I'm parsing the same way in the implementation method, I'm getting the below error:

OSError: Error reading file 'dir/testxsd.xsd': failed to load external entity "dir/testxsd.xsd"

I've tried a couple of other alternatives, such as loading the file from this answer , but doing this gives me an error:

import unittest
from lxml import etree
import os

THIS_DIR = os.path.dirname(os.path.abspath(__file__))

class TestSpecData(unittest.TestCase):
    def setUp(self):
        my_data_path = os.path.join(THIS_DIR, os.pardir, 'dir/testxsd.xsd')
        rootXSD = my_data_path.getroot()

    def test_whatever(self):
        data = sum(1, 2)
        self.assertEqual(data, 3)

if __name__ == '__main__':
    unittest.main()

AttributeError: 'str' object has no attribute 'getroot'

I've also tried this answer , but I'm not familiar with Django so was getting a bunch of errors.

Answer 1

In the second version after your edit, you are calling getroot on a string instead of a parsed XML tree. Still, if you properly parse the file with an absolute path, this could solve your problem.

Schema example ( test.xsd)

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="unqualified">

    <xs:element name="config" type="xs:string" />

</xs:schema>

Python code ( test.py )

import unittest
from lxml import etree
import os

THIS_DIR = os.path.dirname(os.path.abspath(__file__))

class TestSpecData(unittest.TestCase):
    def setUp(self):
        my_data_path = os.path.join(THIS_DIR, 'data/test.xsd')

        tree = etree.parse(my_data_path)
        root = tree.getroot()

    def test_whatever(self):
        data = sum([1, 2])
        self.assertEqual(data, 3)

if __name__ == '__main__':
    unittest.main()

Output

Assuming a folder test that contains test.py , and that test.xsd is in a subfolder called data , and after fixing an error in your test (adding list brackets) the output is

$ python test.py
.
----------------------------------------------------------------------
Ran 1 test in 0.001s

OK