Access Keycloak REST Admin API using a service account (client credential grant) - keycloak

Question

I like to manage keycloak from my own application:create user & clients, display users & client. As this is not a real user but a machine I would like to use a service account with a client credential grant as proposed in How to get Keycloak users via REST without admin account . To realize this I:
create a realm
inside the real created a client
configured the access type of the client to "confidential" saved and activated the "Service Accounts Enabled" option that will apear after the save.
enable under scopes the client-roles of the "real-management" (see screenshot)
requested an access token with the "username:password" base64 encoded in the header
curl -X POST 'http://accounts.d10l.de/auth/realms/d10l/protocol/openid-connect/token' \
-H "Content-Type: application/x-www-form-urlencoded" \
-H "Authorization: Basic ZGV2ZWxvcGVyLXBvcnRhbDpmZGRmYzM4Yy05MzAyLTRlZmQtYTM3Yy1lMWFmZGEyMmRhMzc=" \
-d 'grant_type=client_credentials' \
| jq -r '.access_token'
Try to access the users using the access token:
curl -I GET 'http://accounts.d10l.de/auth/admin/realms/d10l/users/' \
-H "Authorization: Bearer eyJhbGciOiJSUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICIxRVdoNENFUjIweDY5SlBCekU4dU9GdXF4R2NVNlVfWmpTNTQ5bmd2QjNjIn0.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.D_XnpF1rwCayup8h4UXM4AGWkY_xQo40X-yIlWhmqaxkVh1FQy24932VDRCAmxYHcrwazRMqO7snXmre3_8YF5R9Dt8GYjiBorECvQ9X_nBwunmHqnGxIeE64c2GXiz6zSjdgQJQE8fH10NsLyFWHQ-lBPsBwZBsrkKQ5QUEU2qjE7rDRPtYLJPB94BSE4QGfedmRIbvg39snVkClBDUmuBTq_Rc4p7kV69h0a2Mb1sgEr3MdB4RcsOe3gJPZVVtu7gZuGqcAQKMYgtybArF3OXz37w8hjUp6FABxDcvY7K-jsGxXn0hSU0OB7wxAWY9vP4ar4tQYlKxNjs46rPLWw"
But the response is a 403:
url: (6) Could not resolve host: GET
HTTP/1.1 403 Forbidden
content-length: 0
date: Sat, 08 Sep 2018 19:42:06 GMT
How/Is it possible accessing the Admin REST API from a new service account through a client credential grant?

Answer 1

Keycloak differentiates between the Scopes/Scope mapping & the roles management.
The Scopes tab: you see in the question above only manages the roles that a client is allowed to request.
For the client credential grant to work these roles must be assigned to the client in the "Service Account Roles" Tab.
So in the end the client receive a token that is the intersection of both of those configurations.
Source: https://www.keycloak.org/docs/latest/server_admin/index.html#_service_accounts