A flow should be able to change the permission of an item in a SharePoint List/document library; this is a very popular pattern in Sharepoint workflows
The following two actions should now be available:
1. Grant access to an item or a folder
2. Stop sharing an item or folder
Please check out these new actions in the SharePoint connector and let us know if you have any feedback!
@NickO the solution controls the user's permissions and can be controled so that they don't have "Full Control". The Full control permission is what will allow an user to update permission for others on the list item. If you don't want them to have it, keep their permissions to Edit, Contribute, Read, or design (Reference: https://docs.microsoft.com/en-us/sharepoint/understanding-permission-levels).
@NickO I updated my post and Flow. Now it includes security actions preventing non-authorizing Flow run.
We need this, too.
Happy to share that we have started implementing flow actions to grant access to items and files in SharePoint. We will share more details as we get closer to the release.