public override Task GrantClientCredentials(OAuthGrantClientCredentialsContext context) {
var identity = new ClaimsIdentity(AuthenticationType.Anonymous);
var systemUtc = new SystemClock().UtcNow;
var ticket = new AuthenticationTicket(identity, new AuthenticationProperties {
IssuedUtc = systemUtc,
ExpiresUtc = systemUtc.AddMinutes(20)
});
context.Validated(ticket);
return base.GrantClientCredentials(context);
}
