Need custom script written for CRM to connect to API to push notifications - ASP

Current business portal built on ASP.NET - API key already developed for each user. Requirement: I need a script/connector to be written which should be adaptable for any CRM system. The script should be able to push data directly from the CRM calendar to ASP server and be able to authenticate the API key of current user for delivery of content. Delivery - 10 days.