We have a OAuth 2.0 Client Registration configured the 'grant type' as SAML Bearer. 

We are trying to use /prweb/api/oauth2/v1/token API to get the access token in order to use that token in making our DX API calls. However, the parameters to set in the request when the grant type is SAML bearer is unclear. We tested with other grant types like client credentials and password credentials and this  /prweb/api/oauth2/v1/token  endpoint returns an access token successfully but we need more information on what parameters to pass when it is SAML bearer grant type. What I found is below:

Set the header of 'Content-Type', 'application/x-www-form-urlencoded'

client_id ( we can get from Pega OAuth 2.0 Client Registration: )

client_secret ( we can get from Pega OAuth 2.0 Client Registration: )

grant_type --- ? what will be the value for SAML ? i tried few things like urn:ietf:params:oauth:grant-type:saml2-bearer or SAML or saml2-bearer

scope ---- As per one of the forums i found in google this param should be passed when it is SAML grant type.

Could you please give us some guidance on how to invoke this end point using the right parameters and values when the grant type is SAML bearer in OAuth 2.0 Client Registration: