The Kloudless Authenticator is an open source, customizable UI tool that allows your users to auth with any cloud app account like Dropbox, Box, Google Drive, Salesforce, Microsoft SharePoint, Office 365, Slack and more. You can embed this in your app with just two lines of code.
The library lets you open a pop-up that allows the user to choose a cloud service to connect. The pop-up closes once the account has been successfully connected.
The library uses the Kloudless OAuth 2.0 Out-of-band flow to obtain an OAuth access token. The token is verified and used to obtain information on the account that was connected. This data is then returned to your application via a callback.
You can use Kloudless in the cloud or self host on-premises as a Docker container, Amazon Web Services AMI, or OVA for deployment on your private infrastructure.
To learn more, try it out on Github: https://github.com/Kloudless/authenticator
Or view the Kloudless Authentication documentation here: https://developers.kloudless.com/docs/v1/authentication