CLOUDP-298233: Postman SA support

Author: wtrocki

tools/postman/collection-description.md

@@ -7,11 +7,28 @@ This collection is an introduction to the [MongoDB Atlas Administration API](htt
 To test out the MongoDB Atlas Admin API collection, start by [creating a free MongoDB Atlas cluster](https://www.mongodb.com/docs/atlas/tutorial/deploy-free-tier-cluster/).  
 Once you have a cluster, you can [fork this collection](https://learning.postman.com/docs/collaborating-in-postman/using-version-control/forking-elements/\#create-a-fork) into your own workspace in order to manage your MongoDB Atlas resources. Make sure to also fork the MongoDB Atlas Administration API Environment at the same time.
 
-Once you have your cluster up and running, follow [this guide](https://www.mongodb.com/docs/atlas/configure-api-access/) to find your public and private API keys. Set each of these values as secrets in the [Postman Vault](https://learning.postman.com/docs/sending-requests/postman-vault/postman-vault-secrets/): 
+### Authentication Using Service Accounts (OAuth)
+
+Once you have your cluster up and running, follow [this guide](https://www.mongodb.com/docs/atlas/configure-api-access/) to create new Service Account.
+Once created copy your public and private API keys.
+Set each of these values as secrets in the [Postman Vault](https://learning.postman.com/docs/sending-requests/postman-vault/postman-vault-secrets/): 
+
+- Service Account Client ID: \`mongodb-public-clientid\`  
+- Service Account Client Secret: \`mongodb-private-clientsecret\`
+
+#### Digest Authentication
+
+Alternatively to Service Account you can use [API Keys](https://www.mongodb.com/docs/atlas/configure-api-access/) authentication.
+Set each of these values as secrets in the [Postman Vault](https://learning.postman.com/docs/sending-requests/postman-vault/postman-vault-secrets/): 
 
 - public API key as the value for a key named \`mongodb-public-api-key\`  
 - private API key as the value for a key named  \`mongodb-private-api-key\`
 
+Additionally to setting those values you would need to manually configure[Digest Authentication in the Collection Authentication Settings](https://learning.postman.com/docs/sending-requests/authorization/digest-auth/)
+
+
+### Using API 
+
 You can now explore the various endpoints. For each endpoint, edit the query and path variables such as group ID and organization ID. For some requests, like POST requests, editing the body of the request is also required. 
 
 For more details, you can follow along with the [Configuring Atlas in Postman With the Atlas Administration API](https://www.mongodb.com/developer/products/atlas/admin-api-postman/) blog.