Conditionaly adding members to teams

[Taras1185]

Hi,

We have the following requirement: when user wants to join or leave a team, make a call to an external API and depending on the result either allow him to join (or leave), or deny and display a message with the reason. 

Is it possible to implement something like this in teams client either using some API or a custom plugin application?

Thank you in advance.

[#2]

@Taras1185 ,

Currently there is graph API to add member in a teams. Please have a look into Graph API for teams.
User can not be restricted to leave group as user can manually go to manage team and can click on leave team.