In the Expression Editor, you can write a microflow expression to check if the currently logged-in user is the author of the post. Here's an example expression:
[%CurrentUser%] = [%Post/Author%]
hi Woo Ju Kim,
By clicking edit or delete button ,if it is trigers microflow giving microflow access to the particular userrole solves the problem .
otherwise by selecting visibility in the button you can achieve it
1.select visibility by expression
2.By Selecting current user = Userrole or by object owner you can assiate the user
You can manage such object-level access with the XPath constraints of access rules for the given entity. In this case, you do not need adjust the visibility rules at the widget itself.
However this will have an effect only when the given widget element uses direct link to the data (i.e. no additional MF). For example, you a Delete button is assigned to Delete action, but not invoking a MF that processes the deletion. (If you assign a MF invocation, the MF access configuration controls the widget visibility.)
Hope it helps,