Custom integration of CRM Online to Sharepoint On-Prem

Goal: Develop custom module to integrate CRM online to Sharepoint On Premises (https to https, both are on https this way)

Business Need: Business do not want to store the documents in Sharepoint online or any other online

Process: I am going to explain in detail with example code but the steps to be followed:

1. Create Site collection and give permission with a test service account

2. Write Upload and Delete routines using sharepoint SDK

3. Create a webAPI project & publish on a  HTTPS site if there is a requirement for SSL

4. Enable the CORS

5. Enable the conditional access on the CRM

6 Enable the security roles so that only those users can have access to the upload documents

7 Lock it down the WebAPI to be accessible by CRM Online https only

8. Write a javascript ajax Get/Post/Delete to call the WebAPI

9 Testing in Chrome fine but IE failed and we had to send GET in js first and then POST eventually worked 

may be add a SP status button on-load in the html webresource to show the status of SP site collection that way you are awaking the webAPI https to https

Any questions let me know