How to get request digest value from provider hosted app?

Question

I am developing SharePoint 2013 Provider hosted app using javascript REST Api. In order to perform create (POST), or update (MERGE) operations on sharepoint items I need to set

Answer 1

You mus remember that in permissions level exist a check that disable all service under _api

_api/web/lists _api/search/query?querytext=’SharePoint’ _api/SP.UserProfiles.PeopleManager

You enable that ensure

site settings->site permissions->permissions level->read->

Integration client features Use remote interface

I found the solution in https://letrasandnumeros.com/2017/02/28/unauthorizedaccessexception-sharepoint-_api/