Issue with python script while parsing pom file in project

March 22, 2022

I’m having issue extracting version number using python script. Its returning none while running the script. Can someone help me on this ?

Python Script:

import xml.etree.ElementTree as ET

tree = ET.parse('pom.xml')
root = tree.getroot()
releaseVersion = root.find("version")
print(releaseVersion)

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <artifactId>watcher</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <groupId>com.test</groupId>
    <name>file</name>
    <packaging>jar</packaging>

    <parent>
        <artifactId>spring-boot-starter-parent</artifactId>
        <groupId>org.springframework.boot</groupId>
        <relativePath/>
        <version>2.6.1</version> 
    </parent>

</project>

>Solution :

You’re not taking into account that all of your elements are in a default namespace defined by xmlns="http://maven.apache.org/POM/4.0.0" in your <project> element.

So you have to create your query with this namespace.

import xml.etree.ElementTree as ET    
tree = ET.parse('pom.xml')
root = tree.getroot()
NS = { 'maven' : 'http://maven.apache.org/POM/4.0.0' }
releaseVersion = root.find("maven:version",NS)
print(releaseVersion.text)

Here NS = { ... } defines the namespace (in the following referred to by its prefix maven) used in the following XPath expression.