/// <summary>
/// Generates a valid authorization URI for use when doing OAuth authentication.
/// </summary>
/// <param name="plugin">The OAuth authentication plugin details.</param>
/// <param name="state">The state - must not be empty/null - used to passed to the authorization endpoint.</param>
/// <param name="forceLogin">If true then the user will be forced to log in, even if they have already authenticated recently.</param>
/// <returns>The URI that can be shown in a browser to undertake the OAuth flow.</returns>
public static Uri GenerateAuthorizationUri
(
this PluginInfo plugin,
string state,
bool forceLogin = false
)
{
// Sanity.
if (null == plugin)
{
throw new ArgumentNullException(nameof(plugin));
}
if (string.IsNullOrWhiteSpace(state))
{
throw new ArgumentNullException(nameof(state));
}
if (false == plugin.IsOAuthPlugin())
{
throw new ArgumentException("The authentication plugin does not refer to an OAuth authentication type", nameof(plugin));
}
var promptType = forceLogin ? "login" : null;
var redirectUri = plugin.GetAppropriateRedirectUri();
// Build up the URI with mandatory data.
var uriBuilder = new UriBuilder(plugin.Configuration["AuthorizationEndpoint"]?.ToString());
uriBuilder.SetQueryParam("client_id", plugin.Configuration["ClientID"]?.ToString());
uriBuilder.SetQueryParam("redirect_uri", redirectUri);
uriBuilder.SetQueryParam("response_type", "code");
// Add the optional items, if set.
uriBuilder.SetQueryParamIfNotNullOrWhitespace("scope", plugin.Configuration["Scope"]?.ToString());
uriBuilder.SetQueryParamIfNotNullOrWhitespace("state", state);
uriBuilder.SetQueryParamIfNotNullOrWhitespace("prompt", promptType);
uriBuilder.SetQueryParamIfNotNullOrWhitespace("resource", plugin.Configuration["Resource"]?.ToString());
// Return the generated URI.
return(uriBuilder.Uri);
}
