Merge multiple XML files from command line

Question

I have several xml files. They all have the same structure, but were splitted due to file size. So, let's say I have A.xml, B.xml, C.xml and D.xml and want to combine/merge them to combined.xml, using a command line tool.

A.xml

<products>
    <product id="1234"></product>
    ...
</products>

B.xml

<products>
  <product id="5678"></product>
  ...
</products>

etc.

Answer 1

High-tech answer:

Save this Python script as xmlcombine.py:

#!/usr/bin/env python
import sys
from xml.etree import ElementTree

def run(files):
    first = None
    for filename in files:
        data = ElementTree.parse(filename).getroot()
        if first is None:
            first = data
        else:
            first.extend(data)
    if first is not None:
        print ElementTree.tostring(first)

if __name__ == "__main__":
    run(sys.argv[1:])

To combine files, run:

python xmlcombine.py ?.xml > combined.xml

For further enhancement, consider using:

• chmod +x xmlcombine.py: Allows you to omit python in the command line

• xmlcombine.py !(combined).xml > combined.xml: Collects all XML files except the output, but requires bash's extglob option

• xmlcombine.py *.xml | sponge combined.xml: Collects everything in combined.xml as well, but requires the sponge program

• import lxml.etree as ElementTree: Uses a potentially faster XML parser