start
Initiates the Authorization Code redirect flow.
Return
a Result containing an AuthorizationCodeFlowContext with the authorization URL and state on success. On failure the Result wraps PushedAuthorizationRequiredException (PAR is mandated by the server but unavailable) or PushedAuthorizationRequestException (PAR is optional, the request failed, and allowPushedAuthorizationRequestFallback is disabled), in addition to any underlying network or server failure.
When PAR is enabled in OAuth2Client.configuration — or required by the discovered server metadata, regardless of that setting — and a PAR endpoint is discovered, the returned authorization URL is composed with request_uri. This is not limited to custom authorization servers.
Parameters
the registered redirect URI for this client.
the scopes to request. If omitted, the client's configured default scopes are used.
additional query parameters for the authorization endpoint.