sort-pom.py

import xml.etree.ElementTree as ET

ET.register_namespace('', 'http://maven.apache.org/POM/4.0.0')
ns = {'pom': 'http://maven.apache.org/POM/4.0.0'}

root = ET.fromstring(open('pom.xml').read())

def text(elem):
    return next(elem.itertext())

def coord(elem):
    return 

dependency_root = root.find('pom:dependencyManagement/pom:dependencies', ns)
dependencies = root.findall('pom:dependencyManagement/pom:dependencies/pom:dependency', ns)
data = sorted([(d, '{}-{}'.format(text(d.find('pom:groupId', ns)), text(d.find('pom:artifactId', ns)))) for d in dependencies], key=lambda x: x[1])

dependency_root.clear()
for item in data:
    dependency_root.append(item[0])

open('pom.xml-sorted', 'a').write(ET.tostring(root).decode())