Protection check for stakingV4 configs

cmd/node/main.go

@@ -97,6 +97,12 @@ func startNodeRunner(c *cli.Context, log logger.Logger, version string) error {
 		return errCfg
 	}
 
+	// check config here
+	errCheckEpochsCfg := sanityCheckEnableEpochsStakingV4(cfgs, log)
+	if errCheckEpochsCfg != nil {
+		return errCfg
+	}
+
 	errCfgOverride := overridableConfig.OverrideConfigValues(cfgs.PreferencesConfig.Preferences.OverridableConfigTomlValues, cfgs)
 	if errCfgOverride != nil {
 		return errCfgOverride
@@ -248,6 +254,59 @@ func readConfigs(ctx *cli.Context, log logger.Logger) (*config.Configs, error) {
 	}, nil
 }
 
+func sanityCheckEnableEpochsStakingV4(cfg *config.Configs, log logger.Logger) error {
+	enableEpochsCfg := cfg.EpochConfig.EnableEpochs
+	stakingV4StepsInOrder := (enableEpochsCfg.StakingV4Step1EnableEpoch < enableEpochsCfg.StakingV4Step2EnableEpoch) &&
+		(enableEpochsCfg.StakingV4Step2EnableEpoch < enableEpochsCfg.StakingV4Step3EnableEpoch)
+
+	if !stakingV4StepsInOrder {
+		return fmt.Errorf("staking v4 enable epochs are not in ascending order" +
+			"; expected StakingV4Step1EnableEpoch < StakingV4Step2EnableEpoch < StakingV4Step3EnableEpoch")
+	}
+
+	stakingV4StepsInExpectedOrder := (enableEpochsCfg.StakingV4Step1EnableEpoch == enableEpochsCfg.StakingV4Step2EnableEpoch-1) &&
+		(enableEpochsCfg.StakingV4Step2EnableEpoch == enableEpochsCfg.StakingV4Step3EnableEpoch-1)
+	if !stakingV4StepsInExpectedOrder {
+		log.Warn("staking v4 enable epoch steps should be in cardinal order " +
+			"(e.g.: StakingV4Step1EnableEpoch = 2, StakingV4Step2EnableEpoch = 3, StakingV4Step3EnableEpoch = 4)" +
+			"; can leave them as they are for playground purposes" +
+			", but DO NOT use them in production, since system's behavior is undefined")
+	}
+
+	maxNodesConfigAdaptedForStakingV4 := false
+	for idx, maxNodesChangeCfg := range enableEpochsCfg.MaxNodesChangeEnableEpoch {
+		if maxNodesChangeCfg.EpochEnable == enableEpochsCfg.StakingV4Step2EnableEpoch {
+			maxNodesConfigAdaptedForStakingV4 = true
+
+			if idx == 0 {
+				log.Warn(fmt.Sprintf("found config change in MaxNodesChangeEnableEpoch for StakingV4Step3EnableEpoch = %d, ", enableEpochsCfg.StakingV4Step3EnableEpoch) +
+					"but no previous config change entry in MaxNodesChangeEnableEpoch")
+			} else {
+				prevMaxNodesChange := enableEpochsCfg.MaxNodesChangeEnableEpoch[idx-1]
+				if prevMaxNodesChange.NodesToShufflePerShard != maxNodesChangeCfg.NodesToShufflePerShard {
+					log.Warn("previous MaxNodesChangeEnableEpoch.NodesToShufflePerShard != MaxNodesChangeEnableEpoch.NodesToShufflePerShard with EnableEpoch = StakingV4Step3EnableEpoch" +
+						"; can leave them as they are for playground purposes, but DO NOT use them in production, since this will influence rewards")
+				}
+
+				numShards := cfg.GeneralConfig.GeneralSettings.GenesisMaxNumberOfShards
+				expectedMaxNumNodes := prevMaxNodesChange.MaxNumNodes - (numShards + 1) - prevMaxNodesChange.NodesToShufflePerShard
+				if expectedMaxNumNodes != maxNodesChangeCfg.MaxNumNodes {
+					return fmt.Errorf(fmt.Sprintf("expcted MaxNodesChangeEnableEpoch.MaxNumNodes for StakingV4Step3EnableEpoch = %d, but got %d",
+						expectedMaxNumNodes, maxNodesChangeCfg.MaxNumNodes))
+				}
+			}
+
+			break
+		}
+	}
+
+	if !maxNodesConfigAdaptedForStakingV4 {
+		return fmt.Errorf("no MaxNodesChangeEnableEpoch config found for EpochEnable = StakingV4Step3EnableEpoch(%d)", enableEpochsCfg.StakingV4Step3EnableEpoch)
+	}
+
+	return nil
+}
+
 func attachFileLogger(log logger.Logger, flagsConfig *config.ContextFlagsConfig) (factory.FileLoggingHandler, error) {
 	var fileLogging factory.FileLoggingHandler
 	var err error