fix: Fixed issue with context cancelled error leading to connection spikes on Primary instances (#3190)

* fix: Fixed issue with context cancelled error leading to connection spikes on Master

* fix: Added tests

* fix: Updated tests

---------

Co-authored-by: Bhargav Dodla <[email protected]>
Co-authored-by: Nedyalko Dyakov <[email protected]>

Author: 3 people

error.go

@@ -38,6 +38,15 @@ type Error interface {
 
 var _ Error = proto.RedisError("")
 
+func isContextError(err error) bool {
+	switch err {
+	case context.Canceled, context.DeadlineExceeded:
+		return true
+	default:
+		return false
+	}
+}
+
 func shouldRetry(err error, retryTimeout bool) bool {
 	switch err {
 	case io.EOF, io.ErrUnexpectedEOF:

osscluster.go

@@ -1350,7 +1350,9 @@ func (c *ClusterClient) processPipelineNode(
 	_ = node.Client.withProcessPipelineHook(ctx, cmds, func(ctx context.Context, cmds []Cmder) error {
 		cn, err := node.Client.getConn(ctx)
 		if err != nil {
-			node.MarkAsFailing()
+			if !isContextError(err) {
+				node.MarkAsFailing()
+			}
 			_ = c.mapCmdsByNode(ctx, failedCmds, cmds)
 			setCmdsErr(cmds, err)
 			return err

osscluster_test.go

@@ -539,6 +539,39 @@ var _ = Describe("ClusterClient", func() {
 				AfterEach(func() {})
 
 				assertPipeline()
+
+				It("doesn't fail node with context.Canceled error", func() {
+					ctx, cancel := context.WithCancel(context.Background())
+					cancel()
+					pipe.Set(ctx, "A", "A_value", 0)
+					_, err := pipe.Exec(ctx)
+
+					Expect(err).To(HaveOccurred())
+					Expect(errors.Is(err, context.Canceled)).To(BeTrue())
+
+					clientNodes, _ := client.Nodes(ctx, "A")
+
+					for _, node := range clientNodes {
+						Expect(node.Failing()).To(BeFalse())
+					}
+				})
+
+				It("doesn't fail node with context.DeadlineExceeded error", func() {
+					ctx, cancel := context.WithTimeout(context.Background(), 1*time.Nanosecond)
+					defer cancel()
+
+					pipe.Set(ctx, "A", "A_value", 0)
+					_, err := pipe.Exec(ctx)
+
+					Expect(err).To(HaveOccurred())
+					Expect(errors.Is(err, context.DeadlineExceeded)).To(BeTrue())
+
+					clientNodes, _ := client.Nodes(ctx, "A")
+
+					for _, node := range clientNodes {
+						Expect(node.Failing()).To(BeFalse())
+					}
+				})
 			})
 
 			Describe("with TxPipeline", func() {