Implicit Grant

Implicit Grant flow. Supported but not recommendted to use

Implicit flow is not recommended to use since there is a risk of leaking access token without any confirmation it was received by the client. More over, some servers prohibit this flow entirely. Aidbox supports Implicit Grant flow but we don't enjoy it very much.

It is better to switch to Authorization Code Grant with PKCE extension instead

Implicit Grant flow is an alternative for Authorization Code flow. This flow just receives access_token in query string fragment instead of obtaining securecode. It's indented for client-side apps use in order to access an API, typically as Web SPA applications. For more detailed information, read OAuth 2.0 specification.

Basic scheme

Easy way

The easiest way to test Implicit Grant flow is to run through the Aidbox Sandbox UI (Auth -> Sandbox -> Implicit).

Sandbox UI

Authorization Endpoint

GET [base]/auth/authorize

Obtaining access token

Query Parameters

Name	Type	Description
state	string	a value used by the client to maintain state between the request and callback
scope	string	scope of the access request
redirect_uri	string	client redirect URI
client_id	string	client ID
response_type	string	value MUST be set to token

302 Redirect

[redirect_uri]#access_token=YzI3ZjQ1M2MtYzFlYi00ZjI3LWI2MzgtOTQ0MWI0ZmIzZjBi&state=eyJoYXNoIjoiIy9pbXBsaWNpdC9iYXNpYyIsImZvcm0tZGF0YSI6eyJ0eXBlIjoiYmFzaWMiLCJiYXNpYyI6eyJjbGllbnQtaWQiOiJpbXAtY2xpZW50In19LCJmb3JtLXBhdGgiOiJpbXBsaWNpdC1wYWdlIn0%3D

After this request, the resource owner (user) will be redirected to Log-in/Sign-up page.

Example

Next step is granting access to the client:

Example

After granting access the user is redirected to the redirect_uri from the client configuration with access_token in query string fragment.

Example

Create client

POST /Client
Accept: text/yaml
Content-Type: text/yaml

id: imp-client
resourceType: Client
grant_types:
- implicit
auth:
  implicit:
    redirect_uri: http://localhost:3449/auth.html

Request access token

curl -X GET \
  'http://localhost:8081/auth/authorize?
        state=example
        &client_id=imp-client
        &redirect_uri=http%3A%2F%2Flocalhost%3A3449%2Fauth.html
        &response_type=token'

Response

HTTP/1.1 302 Found

Location: http://localhost:3449/auth.html#access_token=ZGE0ZmQzZTYtOGU0OC00MDJhLWFkN2ItZTg5ZmViYjdmNTQ2
&state=example