fix: Resource watcher re-connects should reset currentVersion (#792)

src/KubeOps.Operator/Watcher/ResourceWatcher{TEntity}.cs

@@ -170,16 +170,15 @@ private async Task WatchClientEventsAsync(CancellationToken stoppingToken)
                     {
                         await OnEventAsync(type, entity, stoppingToken);
                     }
-                    catch (KubernetesException e)
+                    catch (KubernetesException e) when (e.Status.Code is (int)HttpStatusCode.GatewayTimeout)
                     {
-                        if (e.Status.Code is (int)HttpStatusCode.Gone or (int)HttpStatusCode.GatewayTimeout)
-                        {
-                            logger.LogDebug(e, "Watch restarting due to 410 HTTP Gone or 504 Gateway Timeout.");
-
-                            break;
-                        }
-
-                        LogReconciliationFailed(e);
+                        logger.LogDebug(e, "Watch restarting due to 504 Gateway Timeout.");
+                        break;
+                    }
+                    catch (KubernetesException e) when (e.Status.Code is (int)HttpStatusCode.Gone)
+                    {
+                        // Special handling when our resource version is outdated.
+                        throw;
                     }
                     catch (Exception e)
                     {
@@ -202,6 +201,11 @@ void LogReconciliationFailed(Exception exception)
                 // Don't throw if the cancellation was indeed requested.
                 break;
             }
+            catch (KubernetesException e) when (e.Status.Code is (int)HttpStatusCode.Gone)
+            {
+                logger.LogDebug(e, "Watch restarting with reset bookmark due to 410 HTTP Gone.");
+                currentVersion = null;
+            }
             catch (Exception e)
             {
                 await OnWatchErrorAsync(e);

test/KubeOps.Operator.Test/LeaderElector/LeaderElectionBackgroundService.Test.cs

@@ -1,58 +1,58 @@
-using FluentAssertions;
-
-using k8s.LeaderElection;
-
-using KubeOps.Operator.LeaderElection;
-
-using Microsoft.Extensions.Logging;
-
-using Moq;
-
-namespace KubeOps.Operator.Test.LeaderElector;
-
-public sealed class LeaderElectionBackgroundServiceTest
-{
-    [Fact]
-    public async Task Elector_Throws_Should_Retry()
-    {
-        // Arrange.
-        var logger = Mock.Of<ILogger<LeaderElectionBackgroundService>>();
-
-        var electionLock = Mock.Of<ILock>();
-
-        var electionLockSubsequentCallEvent = new AutoResetEvent(false);
-        bool hasElectionLockThrown = false;
-        Mock.Get(electionLock)
-            .Setup(electionLock => electionLock.GetAsync(It.IsAny<CancellationToken>()))
-            .Returns<CancellationToken>(
-                async cancellationToken =>
-                {
-                    if (hasElectionLockThrown)
-                    {
-                        // Signal to the test that a subsequent call has been made.
-                        electionLockSubsequentCallEvent.Set();
-
-                        // Delay returning for a long time, allowing the test to stop the background service, in turn cancelling the cancellation token.
-                        await Task.Delay(TimeSpan.FromSeconds(10), cancellationToken);
-                        throw new InvalidOperationException();
-                    }
-
-                    hasElectionLockThrown = true;
-                    throw new Exception("Unit test exception");
-                });
-
-        var leaderElectionConfig = new LeaderElectionConfig(electionLock);
-        var leaderElector = new k8s.LeaderElection.LeaderElector(leaderElectionConfig);
-
-        var leaderElectionBackgroundService = new LeaderElectionBackgroundService(logger, leaderElector);
-
-        // Act / Assert.
-        await leaderElectionBackgroundService.StartAsync(CancellationToken.None);
-
-        // Starting the background service should result in the lock attempt throwing, and then a subsequent attempt being made.
-        // Wait for the subsequent event to be signalled, if we time out the test fails. The retry delay requires us to wait at least 3 seconds.
-        electionLockSubsequentCallEvent.WaitOne(TimeSpan.FromMilliseconds(3100)).Should().BeTrue();
-
-        await leaderElectionBackgroundService.StopAsync(CancellationToken.None);
-    }
-}
+using FluentAssertions;
+
+using k8s.LeaderElection;
+
+using KubeOps.Operator.LeaderElection;
+
+using Microsoft.Extensions.Logging;
+
+using Moq;
+
+namespace KubeOps.Operator.Test.LeaderElector;
+
+public sealed class LeaderElectionBackgroundServiceTest
+{
+    [Fact]
+    public async Task Elector_Throws_Should_Retry()
+    {
+        // Arrange.
+        var logger = Mock.Of<ILogger<LeaderElectionBackgroundService>>();
+
+        var electionLock = Mock.Of<ILock>();
+
+        var electionLockSubsequentCallEvent = new AutoResetEvent(false);
+        bool hasElectionLockThrown = false;
+        Mock.Get(electionLock)
+            .Setup(electionLock => electionLock.GetAsync(It.IsAny<CancellationToken>()))
+            .Returns<CancellationToken>(
+                async cancellationToken =>
+                {
+                    if (hasElectionLockThrown)
+                    {
+                        // Signal to the test that a subsequent call has been made.
+                        electionLockSubsequentCallEvent.Set();
+
+                        // Delay returning for a long time, allowing the test to stop the background service, in turn cancelling the cancellation token.
+                        await Task.Delay(TimeSpan.FromSeconds(10), cancellationToken);
+                        throw new InvalidOperationException();
+                    }
+
+                    hasElectionLockThrown = true;
+                    throw new Exception("Unit test exception");
+                });
+
+        var leaderElectionConfig = new LeaderElectionConfig(electionLock);
+        var leaderElector = new k8s.LeaderElection.LeaderElector(leaderElectionConfig);
+
+        var leaderElectionBackgroundService = new LeaderElectionBackgroundService(logger, leaderElector);
+
+        // Act / Assert.
+        await leaderElectionBackgroundService.StartAsync(CancellationToken.None);
+
+        // Starting the background service should result in the lock attempt throwing, and then a subsequent attempt being made.
+        // Wait for the subsequent event to be signalled, if we time out the test fails. The retry delay requires us to wait at least 3 seconds.
+        electionLockSubsequentCallEvent.WaitOne(TimeSpan.FromMilliseconds(3100)).Should().BeTrue();
+
+        await leaderElectionBackgroundService.StopAsync(CancellationToken.None);
+    }
+}