getOauthAccessToken
Obtains an OAuth2 access token for use with consent-based API endpoints.
Always uses the CIBA grant (grant_type=urn:openid:params:grant-type:ciba), which requires a valid auth_req_id from a prior bcAuthorize call. Passing a blank backChannelAuthorizationRequestId is a programming error: the method emits NetworkResult.Error immediately rather than forwarding an invalid request to the server.
Return
A Flow emitting NetworkResult.Error immediately if backChannelAuthorizationRequestId is blank, otherwise emitting NetworkResult.Loading then a terminal NetworkResult.Success or NetworkResult.Error from the network call.
Parameters
The type of product for which to obtain the OAuth2 access token.
The subscription key for the product.
The target environment (e.g., sandbox or production).
The auth_req_id returned by a prior bcAuthorize call. Must not be blank.