update

Author: terencefan

src/Microsoft.Azure.SignalR.Common/Auth/LocalTokenProvider.cs

@@ -24,11 +24,11 @@ public LocalTokenProvider(
             AccessKey accessKey,
             string audience,
             IEnumerable<Claim> claims,
-            AccessTokenAlgorithm? algorithm = null,
+            AccessTokenAlgorithm algorithm = AccessTokenAlgorithm.HS256,
             TimeSpan? tokenLifetime = null)
         {
             _accessKey = accessKey ?? throw new ArgumentNullException(nameof(accessKey));
-            _algorithm = algorithm ?? AccessTokenAlgorithm.HS256;
+            _algorithm = algorithm;
             _audience = audience;
             _claims = claims;
             _tokenLifetime = tokenLifetime ?? Constants.Periods.DefaultAccessTokenLifetime;

src/Microsoft.Azure.SignalR.Common/Interfaces/IAccessTokenProvider.cs

@@ -5,7 +5,7 @@
 
 namespace Microsoft.Azure.SignalR
 {
-    public interface IAccessTokenProvider
+    internal interface IAccessTokenProvider
     {
         Task<string> ProvideAsync();
     }

src/Microsoft.Azure.SignalR/EndpointProvider/ServiceEndpointProvider.cs

@@ -73,7 +73,7 @@ public IAccessTokenProvider GetServerAccessTokenProvider(string hubName, string
             }
             else
             {
-                throw new NotSupportedException("Unsupported auth type.");
+                throw new NotSupportedException("Access key cannot be null.");
             }
         }