1 files changed, 55 insertions, 0 deletions
diff --git a/src/DotNetOpenAuth.OAuth2.AuthorizationServer/OAuth2/AuthServerUtilities.cs b/src/DotNetOpenAuth.OAuth2.AuthorizationServer/OAuth2/AuthServerUtilities.cs
new file mode 100644
index 0000000..a59eaa7
--- /dev/null
+++ b/src/DotNetOpenAuth.OAuth2.AuthorizationServer/OAuth2/AuthServerUtilities.cs
@@ -0,0 +1,55 @@
+//-----------------------------------------------------------------------
+// <copyright file="AuthServerUtilities.cs" company="Outercurve Foundation">
+//     Copyright (c) Outercurve Foundation. All rights reserved.
+// </copyright>
+//-----------------------------------------------------------------------
+
+namespace DotNetOpenAuth.OAuth2 {
+	using System;
+	using System.Collections.Generic;
+	using System.Diagnostics.Contracts;
+	using System.Globalization;
+	using System.Linq;
+	using System.Text;
+	using DotNetOpenAuth.Messaging;
+
+	/// <summary>
+	/// Utility methods for authorization servers.
+	/// </summary>
+	internal static class AuthServerUtilities {
+		/// <summary>
+		/// Gets information about the client with a given identifier.
+		/// </summary>
+		/// <param name="authorizationServer">The authorization server.</param>
+		/// <param name="clientIdentifier">The client identifier.</param>
+		/// <returns>The client information.  Never null.</returns>
+		internal static IClientDescription GetClientOrThrow(this IAuthorizationServer authorizationServer, string clientIdentifier) {
+			Requires.NotNullOrEmpty(clientIdentifier, "clientIdentifier");
+			Contract.Ensures(Contract.Result<IClientDescription>() != null);
+
+			try {
+				var result = authorizationServer.GetClient(clientIdentifier);
+				ErrorUtilities.VerifyHost(result != null, OAuthStrings.ResultShouldNotBeNull, authorizationServer.GetType().FullName, "GetClient(string)");
+				return result;
+			} catch (KeyNotFoundException ex) {
+				throw ErrorUtilities.Wrap(ex, OAuthStrings.ClientOrTokenSecretNotFound);
+			} catch (ArgumentException ex) {
+				throw ErrorUtilities.Wrap(ex, OAuthStrings.ClientOrTokenSecretNotFound);
+			}
+		}
+
+		/// <summary>
+		/// Verifies a condition is true or throws an exception describing the problem.
+		/// </summary>
+		/// <param name="condition">The condition that evaluates to true to avoid an exception.</param>
+		/// <param name="error">A single error code from <see cref="Protocol.AccessTokenRequestErrorCodes"/>.</param>
+		/// <param name="unformattedDescription">A human-readable UTF-8 encoded text providing additional information, used to assist the client developer in understanding the error that occurred.</param>
+		/// <param name="args">The formatting arguments to generate the actual description.</param>
+		internal static void TokenEndpointVerify(bool condition, string error, string unformattedDescription = null, params object[] args) {
+			if (!condition) {
+				string description = unformattedDescription != null ? string.Format(CultureInfo.CurrentCulture, unformattedDescription, args) : null;
+				throw new TokenEndpointProtocolException(error, description);
+			}
+		}
+	}
+}