[context] tolerate empty candidate name

Author: dustinxie

action/protocol/context.go

@@ -13,7 +13,9 @@ import (
 	"github.com/ethereum/go-ethereum/core/vm"
 	"github.com/iotexproject/go-pkgs/hash"
 	"github.com/iotexproject/iotex-address/address"
+	"github.com/pkg/errors"
 
+	"github.com/iotexproject/iotex-core/v2/action"
 	"github.com/iotexproject/iotex-core/v2/blockchain/genesis"
 	"github.com/iotexproject/iotex-core/v2/pkg/log"
 )
@@ -123,6 +125,7 @@ type (
 		FixUnproductiveDelegates                bool
 		CorrectGasRefund                        bool
 		SufficentBalanceGuarantee               bool
+		TolerateEmptyCandidateName              bool
 		SkipSystemActionNonce                   bool
 		ValidateSystemAction                    bool
 		AllowCorrectChainIDOnly                 bool
@@ -280,6 +283,7 @@ func WithFeatureCtx(ctx context.Context) context.Context {
 			FixUnproductiveDelegates:                g.IsOkhotsk(height),
 			CorrectGasRefund:                        g.IsOkhotsk(height),
 			SufficentBalanceGuarantee:               g.IsOkhotsk(height),
+			TolerateEmptyCandidateName:              g.IsOkhotsk(height) && !g.IsPalau(height),
 			SkipSystemActionNonce:                   g.IsPalau(height),
 			ValidateSystemAction:                    g.IsQuebec(height),
 			AllowCorrectChainIDOnly:                 g.IsQuebec(height),
@@ -307,6 +311,13 @@ func WithFeatureCtx(ctx context.Context) context.Context {
 	)
 }
 
+func (fCtx *FeatureCtx) Tolerate(err error) bool {
+	if fCtx.TolerateEmptyCandidateName && errors.Cause(err) == action.ErrInvalidCanName {
+		return true
+	}
+	return false
+}
+
 // GetFeatureCtx gets FeatureCtx.
 func GetFeatureCtx(ctx context.Context) (FeatureCtx, bool) {
 	fc, ok := ctx.Value(featureContextKey{}).(FeatureCtx)

action/protocol/generic_validator.go

@@ -58,7 +58,8 @@ func (v *GenericValidator) Validate(ctx context.Context, selp *action.SealedEnve
 	if caller == nil {
 		return errors.New("failed to get address")
 	}
-	if err = selp.Envelope.SanityCheck(); err != nil {
+	featureCtx := MustGetFeatureCtx(ctx)
+	if err = selp.Envelope.SanityCheck(); err != nil && !featureCtx.Tolerate(err) {
 		return err
 	}
 	// Reject action if nonce is too low
@@ -67,10 +68,7 @@ func (v *GenericValidator) Validate(ctx context.Context, selp *action.SealedEnve
 			return action.ErrSystemActionNonce
 		}
 	} else {
-		var (
-			nonce      uint64
-			featureCtx = MustGetFeatureCtx(ctx)
-		)
+		var nonce uint64
 		if featureCtx.FixGasAndNonceUpdate || selp.Nonce() != 0 {
 			confirmedState, err := v.accountState(ctx, v.sr, caller)
 			if err != nil {