migrate experimental-downgrade-check-time to downgrade-check-time

Signed-off-by: Ajay Sundar Karuppasamy <ajaysundar@google.com>

server/embed/config.go

@@ -141,6 +141,7 @@ var (
 		"experimental-bootstrap-defrag-threshold-megabytes": "bootstrap-defrag-threshold-megabytes",
 		"experimental-max-learners":                         "max-learners",
 		"experimental-memory-mlock":                         "memory-mlock",
+		"experimental-downgrade-check-time":                 "downgrade-check-time",
 	}
 )
 
@@ -487,7 +488,12 @@ type Config struct {
 	// Setting this is unsafe and will cause data loss.
 	UnsafeNoFsync bool `json:"unsafe-no-fsync"`
 
+	// ExperimentalDowngradeCheckTime is the duration between two downgrade status checks (in seconds).
+	// Deprecated in v3.6 and scheduled to be removed in v3.7.
+	// TODO: Delete `ExperimentalDowngradeCheckTime` in v3.7.
 	ExperimentalDowngradeCheckTime time.Duration `json:"experimental-downgrade-check-time"`
+	// DowngradeCheckTime is the duration between two downgrade status checks (in seconds).
+	DowngradeCheckTime time.Duration `json:"downgrade-check-time"`
 
 	// MemoryMlock enables mlocking of etcd owned memory pages.
 	// The setting improves etcd tail latency in environments were:
@@ -617,6 +623,7 @@ func NewConfig() *Config {
 		EnableGRPCGateway:     true,
 
 		ExperimentalDowngradeCheckTime: DefaultDowngradeCheckTime,
+		DowngradeCheckTime:             DefaultDowngradeCheckTime,
 		MemoryMlock:                    false,
 		// TODO: delete in v3.7
 		ExperimentalMemoryMlock:             false,
@@ -827,7 +834,9 @@ func (cfg *Config) AddFlags(fs *flag.FlagSet) {
 	// TODO: delete in v3.7
 	fs.DurationVar(&cfg.ExperimentalWatchProgressNotifyInterval, "experimental-watch-progress-notify-interval", cfg.ExperimentalWatchProgressNotifyInterval, "Duration of periodic watch progress notifications. Deprecated in v3.6 and will be decommissioned in v3.7. Use --watch-progress-notify-interval instead.")
 	fs.DurationVar(&cfg.WatchProgressNotifyInterval, "watch-progress-notify-interval", cfg.WatchProgressNotifyInterval, "Duration of periodic watch progress notifications.")
-	fs.DurationVar(&cfg.ExperimentalDowngradeCheckTime, "experimental-downgrade-check-time", cfg.ExperimentalDowngradeCheckTime, "Duration of time between two downgrade status checks.")
+	fs.DurationVar(&cfg.DowngradeCheckTime, "downgrade-check-time", cfg.DowngradeCheckTime, "Duration of time between two downgrade status checks.")
+	// TODO: delete in v3.7
+	fs.DurationVar(&cfg.ExperimentalDowngradeCheckTime, "experimental-downgrade-check-time", cfg.ExperimentalDowngradeCheckTime, "Duration of time between two downgrade status checks. Deprecated in v3.6 and will be decommissioned in v3.7. Use --downgrade-check-time instead.")
 	// TODO: delete in v3.7
 	fs.DurationVar(&cfg.ExperimentalWarningApplyDuration, "experimental-warning-apply-duration", cfg.ExperimentalWarningApplyDuration, "Time duration after which a warning is generated if request takes more time. Deprecated in v3.6 and will be decommissioned in v3.7. Use --warning-watch-progress-duration instead.")
 	fs.DurationVar(&cfg.WarningApplyDuration, "warning-apply-duration", cfg.WarningApplyDuration, "Time duration after which a warning is generated if watch progress takes more time.")

server/embed/etcd.go

@@ -229,7 +229,7 @@ func StartEtcd(inCfg *Config) (e *Etcd, err error) {
 		CompactionBatchLimit:                 cfg.CompactionBatchLimit,
 		CompactionSleepInterval:              cfg.ExperimentalCompactionSleepInterval,
 		WatchProgressNotifyInterval:          cfg.WatchProgressNotifyInterval,
-		DowngradeCheckTime:                   cfg.ExperimentalDowngradeCheckTime,
+		DowngradeCheckTime:                   cfg.DowngradeCheckTime,
 		WarningApplyDuration:                 cfg.WarningApplyDuration,
 		WarningUnaryRequestDuration:          cfg.WarningUnaryRequestDuration,
 		MemoryMlock:                          cfg.MemoryMlock,

server/etcdmain/config.go

@@ -72,6 +72,7 @@ var (
 		"experimental-bootstrap-defrag-threshold-megabytes": "--experimental-bootstrap-defrag-threshold-megabytes is deprecated in v3.6 and will be decommissioned in v3.7. Use '--bootstrap-defrag-threshold-megabytes' instead.",
 		"experimental-max-learners":                         "--experimental-max-learners is deprecated in v3.6 and will be decommissioned in v3.7. Use '--max-learners' instead.",
 		"experimental-memory-mlock":                         "--experimental-memory-mlock is deprecated in v3.6 and will be decommissioned in v3.7. Use '--memory-mlock' instead.",
+		"experimental-downgrade-check-time":                 "--experimental-downgrade-check-time is deprecated in v3.6 and will be decommissioned in v3.7. Use '--downgrade-check-time' instead.",
 	}
 )
 
@@ -209,6 +210,10 @@ func (cfg *config) parse(arguments []string) error {
 		cfg.ec.MemoryMlock = cfg.ec.ExperimentalMemoryMlock
 	}
 
+	if cfg.ec.FlagsExplicitlySet["experimental-downgrade-check-time"] {
+		cfg.ec.DowngradeCheckTime = cfg.ec.ExperimentalDowngradeCheckTime
+	}
+
 	// `V2Deprecation` (--v2-deprecation) is deprecated and scheduled for removal in v3.8. The default value is enforced, ignoring user input.
 	cfg.ec.V2Deprecation = cconfig.V2DeprDefault
 

server/etcdmain/config_test.go

@@ -475,6 +475,77 @@ func TestParseFeatureGateFlags(t *testing.T) {
 	}
 }
 
+// TestDowngradeCheckTimeFlagMigration tests the migration from
+// --experimental-downgrade-check-time to --downgrade-check-time
+func TestDowngradeCheckTimeFlagMigration(t *testing.T) {
+	testCases := []struct {
+		name                           string
+		downgradeCheckTime             string
+		experimentalDowngradeCheckTime string
+		wantErr                        bool
+		wantConfig                     time.Duration
+	}{
+		{
+			name:       "default",
+			wantConfig: embed.DefaultDowngradeCheckTime,
+		},
+		{
+			name:                           "cannot set both experimental flag and non experimental flag",
+			experimentalDowngradeCheckTime: "1m",
+			downgradeCheckTime:             "2m",
+			wantErr:                        true,
+		},
+		{
+			name:                           "can set experimental flag",
+			experimentalDowngradeCheckTime: "1m",
+			wantConfig:                     time.Minute,
+		},
+		{
+			name:               "can set non-experimental flag",
+			downgradeCheckTime: "2m",
+			wantConfig:         2 * time.Minute,
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			cmdLineArgs := []string{}
+			yc := struct {
+				ExperimentalDowngradeCheckTime time.Duration `json:"experimental-downgrade-check-time,omitempty"`
+				DowngradeCheckTime             time.Duration `json:"downgrade-check-time,omitempty"`
+			}{}
+
+			if tc.downgradeCheckTime != "" {
+				cmdLineArgs = append(cmdLineArgs, fmt.Sprintf("--downgrade-check-time=%s", tc.downgradeCheckTime))
+				downgradeCheckTime, err := time.ParseDuration(tc.downgradeCheckTime)
+				require.NoError(t, err)
+				yc.DowngradeCheckTime = downgradeCheckTime
+			}
+
+			if tc.experimentalDowngradeCheckTime != "" {
+				cmdLineArgs = append(cmdLineArgs, fmt.Sprintf("--experimental-downgrade-check-time=%s", tc.experimentalDowngradeCheckTime))
+				experimentalDowngradeCheckTime, err := time.ParseDuration(tc.experimentalDowngradeCheckTime)
+				require.NoError(t, err)
+				yc.ExperimentalDowngradeCheckTime = experimentalDowngradeCheckTime
+			}
+
+			cfgFromCmdLine, errFromCmdLine, cfgFromFile, errFromFile := generateCfgsFromFileAndCmdLine(t, yc, cmdLineArgs)
+
+			if tc.wantErr {
+				if errFromCmdLine == nil || errFromFile == nil {
+					t.Fatal("expect parse error")
+				}
+				return
+			}
+			if errFromCmdLine != nil || errFromFile != nil {
+				t.Fatal("error parsing config")
+			}
+
+			require.Equal(t, tc.wantConfig, cfgFromCmdLine.ec.DowngradeCheckTime)
+			require.Equal(t, tc.wantConfig, cfgFromFile.ec.DowngradeCheckTime)
+		})
+	}
+}
+
 // TestCompactHashCheckTimeFlagMigration tests the migration from
 // --experimental-compact-hash-check-time to --compact-hash-check-time
 // TODO: delete in v3.7
@@ -1131,6 +1202,7 @@ func TestConfigFileDeprecatedOptions(t *testing.T) {
 		ExperimentalWarningApplyDuration              time.Duration `json:"experimental-warning-apply-duration,omitempty"`
 		ExperimentalBootstrapDefragThresholdMegabytes uint          `json:"experimental-bootstrap-defrag-threshold-megabytes,omitempty"`
 		ExperimentalMaxLearners                       int           `json:"experimental-max-learners,omitempty"`
+		ExperimentalDowngradeCheckTime                time.Duration `json:"experimental-downgrade-check-time,omitempty"`
 	}
 
 	testCases := []struct {
@@ -1155,6 +1227,7 @@ func TestConfigFileDeprecatedOptions(t *testing.T) {
 				ExperimentalWarningApplyDuration:              3 * time.Minute,
 				ExperimentalBootstrapDefragThresholdMegabytes: 100,
 				ExperimentalMaxLearners:                       1,
+				ExperimentalDowngradeCheckTime:                1 * time.Minute,
 			},
 			expectedFlags: map[string]struct{}{
 				"experimental-compact-hash-check-enabled":           {},
@@ -1165,6 +1238,7 @@ func TestConfigFileDeprecatedOptions(t *testing.T) {
 				"experimental-warning-apply-duration":               {},
 				"experimental-bootstrap-defrag-threshold-megabytes": {},
 				"experimental-max-learners":                         {},
+				"experimental-downgrade-check-time":                 {},
 			},
 		},
 		{

server/etcdmain/help.go

@@ -320,7 +320,11 @@ Experimental feature:
   --experimental-compaction-sleep-interval
     Sets the sleep interval between each compaction batch.
   --experimental-downgrade-check-time
+    Duration of time between two downgrade status checks. Deprecated in v3.6 and will be decommissioned in v3.7. Use "downgrade-check-time" instead.
+  --downgrade-check-time
     Duration of time between two downgrade status checks.
+  --downgrade-check-time
+    Duration of time between two downgrade status checks. Deprecated in v3.6 and will be decommissioned in v3.7. Use "downgrade-check-time" instead.
   --experimental-enable-lease-checkpoint-persist 'false'
     Enable persisting remainingTTL to prevent indefinite auto-renewal of long lived leases. Always enabled in v3.6. Should be used to ensure smooth upgrade from v3.5 clusters with this feature enabled. Requires experimental-enable-lease-checkpoint to be enabled.
   --experimental-memory-mlock