clientv3test: add comments for clientv3test

Signed-off-by: shaoqin4 <[email protected]>

client/v3/ordering/util.go

@@ -29,7 +29,7 @@ func NewOrderViolationSwitchEndpointClosure(c *clientv3.Client) OrderViolationFu
 	violationCount := int32(0)
 	return func(_ clientv3.Op, _ clientv3.OpResponse, _ int64) error {
 		// Each request is assigned by round-robin load-balancer's picker to a different
-		// endpoints. If we cycled them 5 times (even with some level of concurrency),
+		// endpoint. If we cycled them 5 times (even with some level of concurrency),
 		// with high probability no endpoint points on a member with fresh data.
 		// TODO: Ideally we should track members (resp.opp.Header) that returned
 		// stale result and explicitly temporarily disable them in 'picker'.

tests/integration/clientv3/ordering_util_test.go

@@ -24,6 +24,9 @@ import (
 	integration2 "go.etcd.io/etcd/tests/v3/framework/integration"
 )
 
+// TestEndpointSwitchResolvesViolation ensures
+// - ErrNoGreaterRev error is returned from partitioned member when it has stale revision
+// - no more error after partition recovers
 func TestEndpointSwitchResolvesViolation(t *testing.T) {
 	integration2.BeforeTest(t)
 	clus := integration2.NewCluster(t, &integration2.ClusterConfig{Size: 3})
@@ -78,8 +81,16 @@ func TestEndpointSwitchResolvesViolation(t *testing.T) {
 	if err != ordering.ErrNoGreaterRev {
 		t.Fatal("While speaking to partitioned leader, we should get ErrNoGreaterRev error")
 	}
+
+	clus.Members[2].RecoverPartition(t, clus.Members[:2]...)
+	time.Sleep(1 * time.Second) // give enough time for the operation
+	_, err = orderingKv.Get(ctx, "foo", clientv3.WithSerializable())
+	if err != nil {
+		t.Fatal("After partition recovered, third member should recover and return no error")
+	}
 }
 
+// TestUnresolvableOrderViolation ensures ErrNoGreaterRev error is returned when available members only have stale revisions
 func TestUnresolvableOrderViolation(t *testing.T) {
 	integration2.BeforeTest(t)
 	clus := integration2.NewCluster(t, &integration2.ClusterConfig{Size: 5, UseBridge: true})