OAuth 2.0 Implicit Grant

The Implicit Grant is used to grant access tokens to applications in the authorization response.

You can download sample .NET framework code at https://dl1.empowerid.com/files/OAuthTestSampleCode.zip

Implicit Grant

1. Initiate a login request to the EmpowerID Authorization endpoint, https://<EID Server>/oauth/v2/ui/authorize

https://<EID Server>/oauth/v2/ui/authorize
?client_id=xxxxxxxxxxxxxxxxxx
 &redirect_uri=https%3A%2F%2Ftestoauthapp.com%2FcallbackUrl
 &response_type=token id_token
 &state=xxxxxxxxxxxxxxxxxx
 &nonce=xxxxxxxxxxxxxxxxxx

Post Body Parameter	Required/Optional	Description

Post Body Parameter	Required/Optional	Description
`client_id`	required	Must be the EmpowerID OAuth application client identifier.
`redirect_uri`	required	Client endpoint to which the authorization server should redirect after request approval.
`response_type`	required	Must be `token` to initiate authorization code flow. For OpenID connect use `token id_token` as response type
`scope`	required for OpenID Connect	Include `scope=id_token` for OpenID Connect flow.
`state`	required	Random string value sent by the client to maintain session and prevent CSR attacks
`nonce`	required	Random string value sent by the client to uniquely identify each request

2. Authenticate using either EmpowerID credentials or any of the allowed external identity providers.

3. Authorization server redirects to the redirect_uri with the response parameters in the fragment part of URL.

redirect_uri
#access_token=xxxxxxxxxxxxxxxxxx
 &state=xxxxxxxxxxxxxxxxxx
 &token_type=Bearer
 &expires_in=3600
 &id_token= xxxxxxxxxxxxxxxxxx

Implicit Grant using .NET Client Library

1. Initialize ClientSettings by passing the client_id, client_secret, redirect_uri, token_endpoint, authorization_endpoint, tokeninfo_endpoint and userinfo_endpoint. Also initialize a new ImplicitGrant by passing the clientSettings model.

var clientSettings = new ClientSettings(
	“client_id”,
	“client_secret”,
	“redirect_uri”,
	“https://<EID Server>/oauth/v2/token”,
	“https://<EID Server>/oauth/v2/ui/authorize”,
	“https://<EID Server>/oauth/v2/tokeninfo”,
	“https://<EID Server>/oauth/v2/userinfo”);
			
 var handler = new ImplicitGrant(clientSettings);

2. Call the BuildAuthorizationRequestPacket() method to to build the fully qualified URL to redirect for authentication.

3. In the application Callback URL() method, extract the access_token, id_token , etc., from the fragment part of the redirect URL.

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