Work on the basic OAuth implementation in sample

Author: localden

samples/ProtectedMCPClient/Program.cs

@@ -13,7 +13,7 @@ static async Task Main(string[] args)
 
         var serverUrl = "http://localhost:7071/sse";
 
-        var tokenProvider = new SimpleAccessTokenProvider(new Uri(serverUrl));
+        var tokenProvider = new BasicOAuthAuthorizationProvider(new Uri(serverUrl));
         var httpClient = new HttpClient().UseMcpAuthorizationProvider(tokenProvider);
 
         Console.WriteLine();

samples/ProtectedMCPClient/SimpleAccessTokenProvider.cs

@@ -15,15 +15,15 @@ namespace ProtectedMCPClient;
 /// A simple implementation of IAccessTokenProvider that uses a fixed API key.
 /// This is just for demonstration purposes.
 /// </summary>
-public partial class SimpleAccessTokenProvider : IMcpAuthorizationProvider
+public partial class BasicOAuthAuthorizationProvider : IMcpAuthorizationProvider
 {
     private readonly ConcurrentDictionary<string, TokenContainer> _tokenCache = new();
     private readonly Uri _serverUrl;
     private readonly string _clientId;
     private readonly string _clientSecret;
     private readonly Uri _redirectUri;
 
-    public SimpleAccessTokenProvider(Uri serverUrl, string clientId = "demo-client", string clientSecret = "", Uri? redirectUri = null)
+    public BasicOAuthAuthorizationProvider(Uri serverUrl, string clientId = "demo-client", string clientSecret = "", Uri? redirectUri = null)
     {
         _serverUrl = serverUrl ?? throw new ArgumentNullException(nameof(serverUrl));
         _clientId = clientId;

samples/ProtectedMCPClient/Utils/AuthorizationServerUtils.cs

@@ -16,16 +16,26 @@ internal class AuthorizationServerUtils
             CancellationToken cancellationToken = default)
         {
             using var httpClient = new HttpClient();
-
+            
+            // Make sure the base URL ends with a slash to correctly append well-known paths
+            string baseUrl = authorizationServerUrl.ToString();
+            if (!baseUrl.EndsWith("/"))
+            {
+                baseUrl += "/";
+            }
+            
             // Try OpenID Connect configuration endpoint first, then OAuth Authorization Server Metadata endpoint
-            string[] wellKnownEndpoints = {
-            "/.well-known/openid-configuration",
-            "/.well-known/oauth-authorization-server"
-        };
+            string[] wellKnownPaths = {
+                ".well-known/openid-configuration",
+                ".well-known/oauth-authorization-server"
+            };
 
-            foreach (var endpoint in wellKnownEndpoints)
+            foreach (var path in wellKnownPaths)
             {
-                var metadataUrl = new Uri(authorizationServerUrl, endpoint);
+                // Simply combine the base URL (now with trailing slash) with the path (without leading slash)
+                var metadataUrl = new Uri(baseUrl + path);
+                Console.WriteLine($"Trying authorization server metadata endpoint: {metadataUrl}");
+                
                 var metadata = await TryFetchMetadataAsync(httpClient, metadataUrl, cancellationToken);
                 if (metadata != null)
                 {
@@ -54,13 +64,17 @@ internal class AuthorizationServerUtils
                 if (response.IsSuccessStatusCode)
                 {
                     var content = await response.Content.ReadAsStreamAsync();
-                    return await JsonSerializer.DeserializeAsync<AuthorizationServerMetadata>(content, new JsonSerializerOptions() {  WriteIndented = true },
+                    return await JsonSerializer.DeserializeAsync<AuthorizationServerMetadata>(content,
+                        new JsonSerializerOptions
+                        {
+                            PropertyNameCaseInsensitive = true,
+                        },
                         cancellationToken);
                 }
             }
-            catch (Exception)
+            catch (Exception ex)
             {
-                // Ignore exceptions and return null
+                Console.WriteLine($"Error fetching metadata from {metadataUrl}: {ex.Message}");
             }
 
             return null;