MetasploitDataModels exists to do several key things:
- Allow code sharing between Metasploit Framework (MSF) and the commercial
versions of Metasploit (Community, Express, Pro -- usually referred to
collectively as "Pro")
- Give developers a lightweight entry point to MSF's backend for use in
developing tools that gather data intended for later use with Metasploit
(e.g. specialized scanners)
- Make it easy to keep commercial stuff private while increasing the
functionality of the open-source tools we provide to the community

WWW: https://github.com/rapid7/metasploit_data_models