We run Moodle version 3.1.x and have no plans to upgrade before Summer 2018. To get around all the unoconv conversion issues we wrote our own google converter script. The script is a drop in replacement for unoconv. I have attached the script in case it is useful for someone else.
- python (should be installed already if you are using unconv)
- Google Service Key (json) for a project that has google drive api enabled (https://console.developers.google.com/flows/enableapi?apiid=drive)
- Put the script files into a folder (e.g. /usr/local/bin/converter)
- pip install --upgrade google-api-python-client
- Put the service key from google in this folder, rename the file to privatekey.json
- Set appropriate permissions on convert and converter.py (same as unoconv, your apache user will need to be able to execute this)
- Change your unoconv path in moodle to the convert script (/usr/local/bin/converter/convert in this example)
Hope this helps someone.