After creating an OAuth 2.0 scope and client and assigning the scope to the client, we can test the configuration. To do this, we need to log on in Keycloak as the OAuth 2.0 client. Keycloak will then validate the client and provide the Access Tokens and the scope(s) assigned to the client.

I will use Postman to test the setup. The Postman requests can be found in my GitLab repository. The request is as following:

• Type: POST
• URL: http://localhost:8080/auth/realms/master/protocol/openid-connect/token
• Header: Content-Type application/x-www-form-urlencoded
• Body: grant_type=client_credentials&client_id=oidclient&client_secret=7bc40a29-3eba-4c01-a9f1-9ebbb2eb8e9c

To authenticate, you need to send the client_id and client secret. These are the same values as for the client in Keycloak.

client_id: oidclient
client_secret: 7bc40a29-3eba-4c01-a9f1-9ebbb2eb8e9c

The parameter grant_type informs Keycloak about the authentification type we want. Client_credentials means that we send the client secret, and together with the client id this authenticates the client. Make sure to protect the client secret! This also explains why HTTPS is a minimum requirement.

grant_type: client_credentials

Result

Keycloak returns the JWT, including the access and refresh token as well as the scope. The assigned scope ZDEMO_CDS_SALESORDERITEM_CDS_0001 is included, allowing the client to access resources that are assigned to that scope.

{
   "access_token": "eyJhbGciOiJSUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICIyeFlIOWNnTThaSzl2Rm1nSEN3QzFiMlRWQzdCZGNldWIyTjB0SGRjU3dZIn0.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.CTrO-XuNM0pxa3xrJNZqGTkPzd88_AcvVKtbG7dy6cMwg_n8f1P2k2afoQMG-sN6JQzQ-Ei_0OIGkXrV6TGWLZqBI3Tgu3NKDoLMWu1PS7N9YA1ubXJN_277L91usWzqmaE_9o5Q6ubenh319tyBL5JUqe5veEfv5WabzwsbPqbx7BfiTf3iE0_xEyWrdXCT64s60hGRSUZqC8Pgz2qLKArfDF_Bs_w20R7Cr50qHx3WJQNO-w_X2DiufmgKD5Cb8Ue8TlpA9o5F88ZKzce-GVplJKY8d35Wjr07DuDTVFQzSWsBSM0Oi0FKuBYGy4mfXjcz8g0tKtcplf2UFurqmA",
    "expires_in": 3600,
    "refresh_expires_in": 1800,
   "refresh_token": "eyJhbGciOiJIUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICJmZmI5NDQ5ZS02MGIxLTQyZTMtYmEwYy1iNjQ0NDc0MjZiNDQifQ.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.blSzmr6gHXIhHY2ikAEXDiBfVQ17eVJsiWFdly8Krkk",
    "token_type": "bearer",
    "not-before-policy": 0,
    "session_state": "76cd1965-1ab8-435d-958b-cb4418c59b08",
    "scope": "ZDEMO_CDS_SALESORDERITEM_CDS_0001 profile email"
}

The content is encoded. Using a site like jwt.io, the content of the tokens can be decoded. For the access token:

{
	"jti": "38358943-c04f-4a19-95d1-0269a604e2be",
	"exp": 1574240042,
	"nbf": 0,
	"iat": 1574136442,
	"iss": "http://localhost:8080/auth/realms/master",
	"aud": "account",
	"sub": "0e2d10b2-4093-4e36-b22b-4418811965c8",
	"typ": "Bearer",
	"azp": "oidclient",
	"auth_time": 0,
	"session_state": "76cd1965-1ab8-435d-958b-cb4418c59b08",
	"acr": "1",
	"realm_access": {
		"roles": [
			"offline_access",
			"uma_authorization"
		]
	},
	"resource_access": {
		"account": {
			"roles": [
				"manage-account",
				"manage-account-links",
				"view-profile"
			]
		}
	},
	"scope": "ZDEMO_CDS_SALESORDERITEM_CDS_0001 profile email",
	"email_verified": false,
	"clientHost": "168.192.0.1",
	"clientId": "oidclient",
	"preferred_username": "service-account-oidclient",
	"clientAddress": "172.17.0.1",
	"email": "service-account-oidclient@placeholder.org"
}