/// <summary>
/// Check if the specified client ID is valid.
/// </summary>
/// <param name="context">The authorization endpoint specific context.</param>
/// <returns>A <see cref="Task{Application}"/> whose result represents the specified client ID specific application. </returns>
/// <exception cref="ArgumentNullException">Specified <paramref name="context"/> is null.</exception>
protected virtual async Task <Application> ValidateClientIdAsync(OAuthContext context)
{
Guard.ArgumentNotNull(context, nameof(context));
var clientId = ((context as AuthorizationContext)?.ClientId)
?? (context as TokenContext)?.ClientId;
if (string.IsNullOrEmpty(clientId))
{
return(null);
}
var application = await ApplicationStore.GetByClientIdAsync(clientId);
if (null == application)
{
context.Failed(OAuthErrors.UnauthorizedClient.UnregisteredApplication, clientId);
}
return(application);
}