Bash and Python scripts to unzip and modify an OpenOffice odt document

.odt files are actually containers (you can see one using unzip -l document.odt). Within the container, content is in the content.xml file. Script info source

Heres what Ive figured out about opening, modifying, and saving the content of an .odt file:

• To open the container for editing:
  

  # bash
  $unzip path/container.odt content.xml
  $unzip path/container.odt content.xml -d working/dir/path/
   # -d places content.xml in a different directory.
   # Creates a content.xml file where you want it.
  
  # python
  >>>import zipfile
  >>>odt_file = zipfile.ZipFile(path/to/file.odt,a) 
  >>> # Options are read only, write only, and append to existing
  >>>raw_xml = odt_file.read(content.xml) 
  >>> # Reads content.xml in as a string, doesnt place a file.
  



• Modify the content.xml file by hand, or using a script, or using Python.
  

  >>> # Tip for using python: ElementTree is good at XML, and it can parse a file, but it cannot parse a string!
  >>> # So heres how to make a string look like a file using pythons StringIO module.
  
  >>>import StringIO, xml.etree.ElementTree as ET
  >>>fakefile = StringIO.StringIO(raw_xml) # Pretend raw_xml string is a file called fakefile
  >>>tree = ET.parse(fakefile).getroot() # Parse the fakefile
  >>>fakefile.close() # close() is desired by StringIO to free the buffer
  >>> # Make changes to your tree here.
  



• To restore the container with modified content:
  

  # bash
  zip -j path/container.odt working/dir/path/content.xml
   # The -j flag adds the file content.xml instead of the useless path/content.xml. You need this!
  rm working/dir/path/content.xml # Clean up
  
  # python
  >>>new_xml = ET.tostring(tree) # If youre exporting from an ElementTree
  >>>odt_file.writestr(content.xml, new_xml)
  >>>odt_file.close()
  

• Putting it all together in bash:
  

  cd path/to/working/directory
  cp path/to/template_filename.odt working_file.odt
  unzip working_file.odt content.xml
  
  # Change the xml...somehow
  
  zip -j working_file.odt content.xml
  rm content.xml
  

• Putting it all together in python:
  

  def edit_the_odt_content(template_filename):
   """Exposes the content of an .odt file so you can modify it."""
   import os, shutil, StringIO, zipfile, xml.etree.ElementTree as ET
  
   shutil.copyfile(template_filename, working_file.odt) # Copy the template into a working file
   odt_file = zipfile.ZipFile(working_file.odt,a)
   xml_string = odt_file.read(content.xml) # Read the zipped content.xml within the .odt as a string
   raw_xml = StringIO.StringIO(xml_string) # Pretend the read string is a file so ElementTree will parse it
   tree = ET.parse(raw_xml).getroot() # Convert raw string to ElementTree
   raw_xml.close()
  
   office_namespace = {urn:oasis:names:tc:opendocument:he tree to find the elements you want to change
   text = body.find(office_namespace + text)
   new_text = your_function_to_modify_the_xml(text) # You can now change the XML any way you wish
   body.remove(text) # Replace the old XML with the new
   body.append(new_text)
  
   new_xml = ET.tostring(tree) # Convert the modified ElementTree back into an XML string
   odt_file.writestr(content.xml, new_xml) # Write the string into the zipped content.xml
   odt_file.close() # Close the zip archive (important!)
   return
  

• Bug: Dont use the zip -m flag! It looks handy, claiming to delete the content.xml file from your file system after adding it to the archive...but instead it will unpredictably delete without adding to the archive.


• You can avoid the whole "containers" muddle by saving an OpenOffice document as a flat file (.fodt). Theres no zipping or unzipping, just open the file in an editor - its xml already. Open the modified .fodt with OpenOffice, and your document is right there. Er, be sure your version of OO supports .fodt before using it. My Mac doesnt, for example.


• OpenOffice also has its own script classes for Python and C, called UNO. However, I havent taken time to dig around through it.