Prevent probing shared services

jdomnitz · Aug 8, 2024 · dc80e4a · dc80e4a
1 parent 4360a64
commit dc80e4a
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Showing 3 changed files with 21 additions and 16 deletions.
diff --git a/src/IServiceDiscovery.cs b/src/IServiceDiscovery.cs
@@ -162,6 +162,7 @@ public interface IServiceDiscovery : IDisposable
         /// </summary>
         /// <param name="profile"></param>
         /// <returns>True if this service conflicts with an existing network service</returns>
+        /// <exception cref="InvalidOperationException">Thrown if a shared profile is probed</exception>
         public bool Probe(ServiceProfile profile);
 
         /// <summary>

diff --git a/src/MulticastClient.cs b/src/MulticastClient.cs
@@ -143,25 +143,25 @@ await sender.Value.SendAsync(
 
         void Listen(UdpClient receiver)
         {
-            // ReceiveAsync does not support cancellation.  So the receiver is disposed
-            // to stop it. See https://github.com/dotnet/corefx/issues/9848
-            Task.Run(async () =>
-            {
-                try
+                // ReceiveAsync does not support cancellation.  So the receiver is disposed
+                // to stop it. See https://github.com/dotnet/corefx/issues/9848
+                Task.Run(async () =>
                 {
-                    var task = receiver.ReceiveAsync();
+                    try
+                    {
+                        var task = receiver.ReceiveAsync();
 
-                    _ = task.ContinueWith(x => Listen(receiver), TaskContinuationOptions.OnlyOnRanToCompletion | TaskContinuationOptions.RunContinuationsAsynchronously);
+                        _ = task.ContinueWith(x => Listen(receiver), TaskContinuationOptions.OnlyOnRanToCompletion | TaskContinuationOptions.RunContinuationsAsynchronously);
 
-                    _ = task.ContinueWith(x => MessageReceived?.Invoke(this, x.Result), TaskContinuationOptions.OnlyOnRanToCompletion | TaskContinuationOptions.RunContinuationsAsynchronously);
+                        _ = task.ContinueWith(x => MessageReceived?.Invoke(this, x.Result), TaskContinuationOptions.OnlyOnRanToCompletion | TaskContinuationOptions.RunContinuationsAsynchronously);
 
-                    await task.ConfigureAwait(false);
-                }
-                catch
-                {
-                    return;
-                }
-            });
+                        await task.ConfigureAwait(false);
+                    }
+                    catch
+                    {
+                        return;
+                    }
+                });
         }
 
         IEnumerable<IPAddress> GetNetworkInterfaceLocalAddresses(NetworkInterface nic)

diff --git a/src/ServiceDiscovery.cs b/src/ServiceDiscovery.cs
@@ -258,12 +258,16 @@ public void Advertise(ServiceProfile service)
         }
 
         /// <summary>
-        /// Probe the network to ensure the service is unique.
+        /// Probe the network to ensure the service is unique. Shared profiles should skip this step.
         /// </summary>
         /// <param name="profile"></param>
         /// <returns>True if this service conflicts with an existing network service</returns>
+        /// <exception cref="InvalidOperationException">Thrown if a shared profile is probed</exception>
         public bool Probe(ServiceProfile profile)
         {
+            if (profile.SharedProfile)
+                throw new InvalidOperationException("Shared profiles should not be probed");
+
             bool conflict = false;
             EventHandler<MessageEventArgs> handler = (s, e) =>
             {