Remove v2 apply logic

v2 store is no longer available in v3.6. We can remove apply logic for it as they will never be used. Only v2 PUT is neeeded as it applies to v3 storage and etcd v3.5 uses it for setting member attributes and cluster version. Signed-off-by: Marek Siarkowicz <[email protected]>
serathius · Nov 22, 2023 · b5ef67a · b5ef67a
1 parent fd0882b
commit b5ef67a
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Showing 4 changed files with 101 additions and 365 deletions.
diff --git a/server/config/v2_deprecation.go b/server/config/v2_deprecation.go
@@ -17,8 +17,6 @@ package config
 type V2DeprecationEnum string
 
 const (
-	// No longer supported in v3.6
-	V2_DEPR_0_NOT_YET = V2DeprecationEnum("not-yet")
 	// Default in v3.6.  Meaningful v2 state is not allowed.
 	// The V2 files are maintained for v3.5 rollback.
 	V2_DEPR_1_WRITE_ONLY = V2DeprecationEnum("write-only")

diff --git a/server/etcdserver/apply_v2.go b/server/etcdserver/apply_v2.go
@@ -22,6 +22,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/coreos/go-semver/semver"
+	"go.etcd.io/etcd/server/v3/config"
 
 	"go.etcd.io/etcd/pkg/v3/pbutil"
 	"go.etcd.io/etcd/server/v3/etcdserver/api"
@@ -37,11 +38,7 @@ const v2Version = "v2"
 
 // ApplierV2 is the interface for processing V2 raft messages
 type ApplierV2 interface {
-	Delete(r *RequestV2) Response
-	Post(r *RequestV2) Response
 	Put(r *RequestV2, shouldApplyV3 membership.ShouldApplyV3) Response
-	QGet(r *RequestV2) Response
-	Sync(r *RequestV2) Response
 }
 
 func NewApplierV2(lg *zap.Logger, s v2store.Store, c *membership.RaftCluster) ApplierV2 {
@@ -57,64 +54,28 @@ type applierV2store struct {
 	cluster *membership.RaftCluster
 }
 
-func (a *applierV2store) Delete(r *RequestV2) Response {
-	switch {
-	case r.PrevIndex > 0 || r.PrevValue != "":
-		return toResponse(a.store.CompareAndDelete(r.Path, r.PrevValue, r.PrevIndex))
-	default:
-		return toResponse(a.store.Delete(r.Path, r.Dir, r.Recursive))
-	}
-}
-
-func (a *applierV2store) Post(r *RequestV2) Response {
-	return toResponse(a.store.Create(r.Path, r.Dir, r.Val, true, r.TTLOptions()))
-}
-
 func (a *applierV2store) Put(r *RequestV2, shouldApplyV3 membership.ShouldApplyV3) Response {
-	ttlOptions := r.TTLOptions()
-	exists, existsSet := pbutil.GetBool(r.PrevExist)
-	switch {
-	case existsSet:
-		if exists {
-			if r.PrevIndex == 0 && r.PrevValue == "" {
-				return toResponse(a.store.Update(r.Path, r.Val, ttlOptions))
-			}
-			return toResponse(a.store.CompareAndSwap(r.Path, r.PrevValue, r.PrevIndex, r.Val, ttlOptions))
+	if storeMemberAttributeRegexp.MatchString(r.Path) {
+		id := membership.MustParseMemberIDFromKey(a.lg, path.Dir(r.Path))
+		var attr membership.Attributes
+		if err := json.Unmarshal([]byte(r.Val), &attr); err != nil {
+			a.lg.Panic("failed to unmarshal", zap.String("value", r.Val), zap.Error(err))
 		}
-		return toResponse(a.store.Create(r.Path, r.Dir, r.Val, false, ttlOptions))
-	case r.PrevIndex > 0 || r.PrevValue != "":
-		return toResponse(a.store.CompareAndSwap(r.Path, r.PrevValue, r.PrevIndex, r.Val, ttlOptions))
-	default:
-		if storeMemberAttributeRegexp.MatchString(r.Path) {
-			id := membership.MustParseMemberIDFromKey(a.lg, path.Dir(r.Path))
-			var attr membership.Attributes
-			if err := json.Unmarshal([]byte(r.Val), &attr); err != nil {
-				a.lg.Panic("failed to unmarshal", zap.String("value", r.Val), zap.Error(err))
-			}
-			if a.cluster != nil {
-				a.cluster.UpdateAttributes(id, attr, shouldApplyV3)
-			}
-			// return an empty response since there is no consumer.
-			return Response{}
+		if a.cluster != nil {
+			a.cluster.UpdateAttributes(id, attr, shouldApplyV3)
 		}
-		// TODO remove v2 version set to avoid the conflict between v2 and v3 in etcd 3.6
-		if r.Path == membership.StoreClusterVersionKey() {
-			if a.cluster != nil {
-				// persist to backend given v2store can be very stale
-				a.cluster.SetVersion(semver.Must(semver.NewVersion(r.Val)), api.UpdateCapability, shouldApplyV3)
-			}
-			return Response{}
+		// return an empty response since there is no consumer.
+		return Response{}
+	}
+	// TODO remove v2 version set to avoid the conflict between v2 and v3 in etcd 3.6
+	if r.Path == membership.StoreClusterVersionKey() {
+		if a.cluster != nil {
+			// persist to backend given v2store can be very stale
+			a.cluster.SetVersion(semver.Must(semver.NewVersion(r.Val)), api.UpdateCapability, shouldApplyV3)
 		}
-		return toResponse(a.store.Set(r.Path, r.Dir, r.Val, ttlOptions))
+		return Response{}
 	}
-}
-
-func (a *applierV2store) QGet(r *RequestV2) Response {
-	return toResponse(a.store.Get(r.Path, r.Recursive, r.Sorted))
-}
-
-func (a *applierV2store) Sync(r *RequestV2) Response {
-	a.store.DeleteExpiredKeys(time.Unix(0, r.Time))
+	a.lg.Panic("detected disallowed v2 WAL for stage --v2-deprecation=write-only", zap.String("method", r.Method))
 	return Response{}
 }
 
@@ -136,16 +97,13 @@ func (s *EtcdServer) applyV2Request(r *RequestV2, shouldApplyV3 membership.Shoul
 	}(time.Now())
 
 	switch r.Method {
-	case "POST":
-		return s.applyV2.Post(r)
 	case "PUT":
 		return s.applyV2.Put(r, shouldApplyV3)
-	case "DELETE":
-		return s.applyV2.Delete(r)
-	case "QGET":
-		return s.applyV2.QGet(r)
-	case "SYNC":
-		return s.applyV2.Sync(r)
+	case "POST", "DELETE", "QGET", "SYNC":
+		if s.Cfg.V2Deprecation.IsAtLeast(config.V2_DEPR_1_WRITE_ONLY) {
+			s.lg.Panic("detected disallowed v2 WAL for stage --v2-deprecation=write-only", zap.String("method", r.Method))
+		}
+		return Response{}
 	default:
 		// This should never be reached, but just in case:
 		return Response{Err: errors.ErrUnknownMethod}
@@ -160,7 +118,3 @@ func (r *RequestV2) TTLOptions() v2store.TTLOptionSet {
 	}
 	return ttlOptions
 }
-
-func toResponse(ev *v2store.Event, err error) Response {
-	return Response{Event: ev, Err: err}
-}