Building a Createandassociate message in Postman -- need header help

API and Webhooks Meetings
1

I am trying to build a post message using the Zoom LTI Pro API in Postman. Specifically a createAndAssociate post message. I found the article on how to do this in the Zoom support.

I understand all the elements of the body, which is the request schema well enough that I believe I have this part correct.

Where I need some help is the request header section. There is step #3, which is creating the signature; the query parameters are fairly straightforward. The part that I am failing is how do I complete step #3 and step#4:

  1. The signature is calculated by passing the base string and secret to the HMAC-SHA1 hashing algorithm. The calculated signature is then converted to aencodeBase64URLSafeString.

  2. Pass the value obtained from step 3 in the X-Lti-Signatureheade

Any help or a sample that includes that part of the process would be very much appreciated.