This addon extends the functionality of the [fs_storage](https://github.com/OCA/storage/tree/18.0/fs_storage) module to allow the system to use Microsoft Drives (OneDrive, Sharepoint) as a storage backend.

All the interactions with Microsoft SharePoint are done through the Microsoft Graph API, which is a RESTful web API that enables you to access Microsoft Cloud service resources. To authenticate with Microsoft Graph, the addon uses the OAuth 2.0 protocol, which is a standard for authorization that allows third-party applications to access user data without exposing their credentials. All the calls are done using the credentials of the odoo user performing the action, which means that the user must have linked their Microsoft SharePoint account to Odoo in order to use this addon. See the [microsoft_drive_account](https://github.com/OCA/storage/tree/18.0/microsoft_drive_account) module documentation for more information on how to link a Microsoft Drive account to an Odoo user.

When calls are made to the Microsoft Graph API through this addon, the addon will check if the credentials are still valid. If they are not, it will refresh them using the refresh token that was obtained during the initial authentication process. This means that the user does not have to re-authenticate every time their credentials expire, as long as they have granted permission for Odoo to refresh their credentials.