etcd/server/etcdserver/version/downgrade.go
Piotr Tabor 9e1abbab6e Fix goimports in all existing files. Execution of ./scripts/fix.sh
Signed-off-by: Piotr Tabor <ptab@google.com>
2022-12-29 09:41:31 +01:00

77 lines
3.0 KiB
Go

// Copyright 2020 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package version
import (
"github.com/coreos/go-semver/semver"
"go.uber.org/zap"
"go.etcd.io/etcd/api/v3/version"
)
type DowngradeInfo struct {
// TargetVersion is the target downgrade version, if the cluster is not under downgrading,
// the targetVersion will be an empty string
TargetVersion string `json:"target-version"`
// Enabled indicates whether the cluster is enabled to downgrade
Enabled bool `json:"enabled"`
}
func (d *DowngradeInfo) GetTargetVersion() *semver.Version {
return semver.Must(semver.NewVersion(d.TargetVersion))
}
// isValidDowngrade verifies whether the cluster can be downgraded from verFrom to verTo
func isValidDowngrade(verFrom *semver.Version, verTo *semver.Version) bool {
return verTo.Equal(*allowedDowngradeVersion(verFrom))
}
// MustDetectDowngrade will detect local server joining cluster that doesn't support it's version.
func MustDetectDowngrade(lg *zap.Logger, sv, cv *semver.Version) {
// only keep major.minor version for comparison against cluster version
sv = &semver.Version{Major: sv.Major, Minor: sv.Minor}
// if the cluster disables downgrade, check local version against determined cluster version.
// the validation passes when local version is not less than cluster version
if cv != nil && sv.LessThan(*cv) {
lg.Panic(
"invalid downgrade; server version is lower than determined cluster version",
zap.String("current-server-version", sv.String()),
zap.String("determined-cluster-version", version.Cluster(cv.String())),
)
}
}
func allowedDowngradeVersion(ver *semver.Version) *semver.Version {
// Todo: handle the case that downgrading from higher major version(e.g. downgrade from v4.0 to v3.x)
return &semver.Version{Major: ver.Major, Minor: ver.Minor - 1}
}
// IsValidVersionChange checks the two scenario when version is valid to change:
// 1. Downgrade: cluster version is 1 minor version higher than local version,
// cluster version should change.
// 2. Cluster start: when not all members version are available, cluster version
// is set to MinVersion(3.0), when all members are at higher version, cluster version
// is lower than local version, cluster version should change
func IsValidVersionChange(cv *semver.Version, lv *semver.Version) bool {
cv = &semver.Version{Major: cv.Major, Minor: cv.Minor}
lv = &semver.Version{Major: lv.Major, Minor: lv.Minor}
if isValidDowngrade(cv, lv) || (cv.Major == lv.Major && cv.LessThan(*lv)) {
return true
}
return false
}