update dependencies

vendor/github.com/coredns/corefile-migration/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+      represent, as a whole, an original work of authorship. For the purposes
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+      separable from, or merely link (or bind by name) to the interfaces of,
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+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
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+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
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+      Contribution(s) alone or by combination of their Contribution(s)
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+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
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+          notices within Derivative Works that You distribute, alongside
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+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
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+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/coredns/corefile-migration/migration/BUILD

@@ -0,0 +1,31 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = [
+        "migrate.go",
+        "notice.go",
+        "versions.go",
+    ],
+    importmap = "k8s.io/kubernetes/vendor/github.com/coredns/corefile-migration/migration",
+    importpath = "github.com/coredns/corefile-migration/migration",
+    visibility = ["//visibility:public"],
+    deps = ["//vendor/github.com/coredns/corefile-migration/migration/corefile:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [
+        ":package-srcs",
+        "//vendor/github.com/coredns/corefile-migration/migration/corefile:all-srcs",
+    ],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/coredns/corefile-migration/migration/corefile/BUILD

@@ -0,0 +1,24 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "go_default_library",
+    srcs = ["corefile.go"],
+    importmap = "k8s.io/kubernetes/vendor/github.com/coredns/corefile-migration/migration/corefile",
+    importpath = "github.com/coredns/corefile-migration/migration/corefile",
+    visibility = ["//visibility:public"],
+    deps = ["//vendor/github.com/caddyserver/caddy/caddyfile:go_default_library"],
+)
+
+filegroup(
+    name = "package-srcs",
+    srcs = glob(["**"]),
+    tags = ["automanaged"],
+    visibility = ["//visibility:private"],
+)
+
+filegroup(
+    name = "all-srcs",
+    srcs = [":package-srcs"],
+    tags = ["automanaged"],
+    visibility = ["//visibility:public"],
+)

vendor/github.com/coredns/corefile-migration/migration/corefile/corefile.go

@@ -0,0 +1,179 @@
+package corefile
+
+import (
+	"strings"
+
+	"github.com/caddyserver/caddy/caddyfile"
+)
+
+type Corefile struct {
+	Servers []*Server
+}
+
+type Server struct {
+	DomPorts []string
+	Plugins  []*Plugin
+}
+
+type Plugin struct {
+	Name    string
+	Args    []string
+	Options []*Option
+}
+
+type Option struct {
+	Name string
+	Args []string
+}
+
+func New(s string) (*Corefile, error) {
+	c := Corefile{}
+	cc := caddyfile.NewDispenser("migration", strings.NewReader(s))
+	depth := 0
+	var cSvr *Server
+	var cPlg *Plugin
+	for cc.Next() {
+		if cc.Val() == "{" {
+			depth += 1
+			continue
+		} else if cc.Val() == "}" {
+			depth -= 1
+			continue
+		}
+		val := cc.Val()
+		args := cc.RemainingArgs()
+		switch depth {
+		case 0:
+			c.Servers = append(c.Servers,
+				&Server{
+					DomPorts: append([]string{val}, args...),
+				})
+			cSvr = c.Servers[len(c.Servers)-1]
+		case 1:
+			cSvr.Plugins = append(cSvr.Plugins,
+				&Plugin{
+					Name: val,
+					Args: args,
+				})
+			cPlg = cSvr.Plugins[len(cSvr.Plugins)-1]
+		case 2:
+			cPlg.Options = append(cPlg.Options,
+				&Option{
+					Name: val,
+					Args: args,
+				})
+		}
+	}
+	return &c, nil
+}
+
+func (c *Corefile) ToString() (out string) {
+	strs := []string{}
+	for _, s := range c.Servers {
+		strs = append(strs, s.ToString())
+	}
+	return strings.Join(strs, "\n")
+}
+
+func (s *Server) ToString() (out string) {
+	str := strings.Join(s.DomPorts, " ")
+	strs := []string{}
+	for _, p := range s.Plugins {
+		strs = append(strs, strings.Repeat(" ", indent)+p.ToString())
+	}
+	if len(strs) > 0 {
+		str += " {\n" + strings.Join(strs, "\n") + "\n}\n"
+	}
+	return str
+}
+
+func (p *Plugin) ToString() (out string) {
+	str := strings.Join(append([]string{p.Name}, p.Args...), " ")
+	strs := []string{}
+	for _, o := range p.Options {
+		strs = append(strs, strings.Repeat(" ", indent*2)+o.ToString())
+	}
+	if len(strs) > 0 {
+		str += " {\n" + strings.Join(strs, "\n") + "\n" + strings.Repeat(" ", indent*1) + "}"
+	}
+	return str
+}
+
+func (o *Option) ToString() (out string) {
+	str := strings.Join(append([]string{o.Name}, o.Args...), " ")
+	return str
+}
+
+func (s *Server) FindMatch(def []*Server) (*Server, bool) {
+NextServer:
+	for _, sDef := range def {
+		for i, dp := range sDef.DomPorts {
+			if dp == "*" {
+				continue
+			}
+			if dp == "***" {
+				return sDef, true
+			}
+			if i >= len(s.DomPorts) || dp != s.DomPorts[i] {
+				continue NextServer
+			}
+		}
+		if len(sDef.DomPorts) != len(s.DomPorts) {
+			continue
+		}
+		return sDef, true
+	}
+	return nil, false
+}
+
+func (p *Plugin) FindMatch(def []*Plugin) (*Plugin, bool) {
+NextPlugin:
+	for _, pDef := range def {
+		if pDef.Name != p.Name {
+			continue
+		}
+		for i, arg := range pDef.Args {
+			if arg == "*" {
+				continue
+			}
+			if arg == "***" {
+				return pDef, true
+			}
+			if i >= len(p.Args) || arg != p.Args[i] {
+				continue NextPlugin
+			}
+		}
+		if len(pDef.Args) != len(p.Args) {
+			continue
+		}
+		return pDef, true
+	}
+	return nil, false
+}
+
+func (o *Option) FindMatch(def []*Option) (*Option, bool) {
+NextPlugin:
+	for _, oDef := range def {
+		if oDef.Name != o.Name {
+			continue
+		}
+		for i, arg := range oDef.Args {
+			if arg == "*" {
+				continue
+			}
+			if arg == "***" {
+				return oDef, true
+			}
+			if i >= len(o.Args) || arg != o.Args[i] {
+				continue NextPlugin
+			}
+		}
+		if len(oDef.Args) != len(o.Args) {
+			continue
+		}
+		return oDef, true
+	}
+	return nil, false
+}
+
+const indent = 4

vendor/github.com/coredns/corefile-migration/migration/migrate.go

@@ -0,0 +1,445 @@
+package migration
+
+// This package provides a set of functions to help handle migrations of CoreDNS Corefiles to be compatible with new
+// versions of CoreDNS. The task of upgrading CoreDNS is the responsibility of a variety of Kubernetes management tools
+// (e.g. kubeadm and others), and the precise behavior may be different for each one. This library abstracts some basic
+// helper functions that make this easier to implement.
+
+import (
+	"fmt"
+	"sort"
+
+	"github.com/coredns/corefile-migration/migration/corefile"
+)
+
+// Deprecated returns a list of deprecation notifications affecting the guven Corefile.  Notifications are returned for
+// any deprecated, removed, or ignored plugins/directives present in the Corefile.  Notifications are also returned for
+// any new default plugins that would be added in a migration.
+func Deprecated(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) ([]Notice, error) {
+	return getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, all)
+}
+
+// Unsupported returns a list notifications of plugins/options that are not handled supported by this migration tool,
+// but may still be valid in CoreDNS.
+func Unsupported(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) ([]Notice, error) {
+	return getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, unsupported)
+}
+
+func getStatus(fromCoreDNSVersion, toCoreDNSVersion, corefileStr, status string) ([]Notice, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return nil, nil
+	}
+	err := validUpMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return nil, err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return nil, err
+	}
+	notices := []Notice{}
+	v := fromCoreDNSVersion
+	for {
+		v = Versions[v].nextVersion
+		for _, s := range cf.Servers {
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if status == unsupported {
+					if present {
+						continue
+					}
+					notices = append(notices, Notice{Plugin: p.Name, Severity: status, Version: v})
+					continue
+				}
+				if !present {
+					continue
+				}
+				if vp.status != "" && vp.status != newdefault {
+					notices = append(notices, Notice{
+						Plugin:     p.Name,
+						Severity:   vp.status,
+						Version:    v,
+						ReplacedBy: vp.replacedBy,
+						Additional: vp.additional,
+					})
+					continue
+				}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if status == unsupported {
+						if present {
+							continue
+						}
+						notices = append(notices, Notice{
+							Plugin:     p.Name,
+							Option:     o.Name,
+							Severity:   status,
+							Version:    v,
+							ReplacedBy: vo.replacedBy,
+							Additional: vo.additional,
+						})
+						continue
+					}
+					if !present {
+						continue
+					}
+					if vo.status != "" && vo.status != newdefault {
+						notices = append(notices, Notice{Plugin: p.Name, Option: o.Name, Severity: vo.status, Version: v})
+						continue
+					}
+				}
+				if status != unsupported {
+				CheckForNewOptions:
+					for name, vo := range Versions[v].plugins[p.Name].options {
+						if vo.status != newdefault {
+							continue
+						}
+						for _, o := range p.Options {
+							if name == o.Name {
+								continue CheckForNewOptions
+							}
+						}
+						notices = append(notices, Notice{Plugin: p.Name, Option: name, Severity: newdefault, Version: v})
+					}
+				}
+			}
+			if status != unsupported {
+			CheckForNewPlugins:
+				for name, vp := range Versions[v].plugins {
+					if vp.status != newdefault {
+						continue
+					}
+					for _, p := range s.Plugins {
+						if name == p.Name {
+							continue CheckForNewPlugins
+						}
+					}
+					notices = append(notices, Notice{Plugin: name, Option: "", Severity: newdefault, Version: v})
+				}
+			}
+		}
+		if v == toCoreDNSVersion {
+			break
+		}
+	}
+	return notices, nil
+}
+
+// Migrate returns the Corefile converted to toCoreDNSVersion, or an error if it cannot.  This function only accepts
+// a forward migration, where the destination version is => the start version.
+// If deprecations is true, deprecated plugins/options will be migrated as soon as they are deprecated.
+// If deprecations is false, deprecated plugins/options will be migrated only once they become removed or ignored.
+func Migrate(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string, deprecations bool) (string, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return corefileStr, nil
+	}
+	err := validUpMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return "", err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return "", err
+	}
+	v := fromCoreDNSVersion
+	for {
+		v = Versions[v].nextVersion
+		newSrvs := []*corefile.Server{}
+		for _, s := range cf.Servers {
+			newPlugs := []*corefile.Plugin{}
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if !present {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if !deprecations && vp.status == deprecated {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if vp.action != nil {
+					p, err := vp.action(p)
+					if err != nil {
+						return "", err
+					}
+					if p == nil {
+						// remove plugin, skip options processing
+						continue
+					}
+				}
+				newOpts := []*corefile.Option{}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if !present {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if !deprecations && vo.status == deprecated {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if vo.action == nil {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					o, err := vo.action(o)
+					if err != nil {
+						return "", err
+					}
+					if o == nil {
+						// remove option
+						continue
+					}
+					newOpts = append(newOpts, o)
+				}
+				newPlug := &corefile.Plugin{
+					Name:    p.Name,
+					Args:    p.Args,
+					Options: newOpts,
+				}
+			CheckForNewOptions:
+				for name, vo := range Versions[v].plugins[p.Name].options {
+					if vo.status != newdefault {
+						continue
+					}
+					for _, o := range p.Options {
+						if name == o.Name {
+							continue CheckForNewOptions
+						}
+					}
+					newPlug, err = vo.add(newPlug)
+					if err != nil {
+						return "", err
+					}
+				}
+
+				newPlugs = append(newPlugs, newPlug)
+			}
+			newSrv := &corefile.Server{
+				DomPorts: s.DomPorts,
+				Plugins:  newPlugs,
+			}
+		CheckForNewPlugins:
+			for name, vp := range Versions[v].plugins {
+				if vp.status != newdefault {
+					continue
+				}
+				for _, p := range s.Plugins {
+					if name == p.Name {
+						continue CheckForNewPlugins
+					}
+				}
+				newSrv, err = vp.add(newSrv)
+				if err != nil {
+					return "", err
+				}
+			}
+
+			newSrvs = append(newSrvs, newSrv)
+		}
+
+		cf = &corefile.Corefile{Servers: newSrvs}
+
+		// apply any global corefile level post processing
+		if Versions[v].postProcess != nil {
+			cf, err = Versions[v].postProcess(cf)
+			if err != nil {
+				return "", err
+			}
+		}
+
+		if v == toCoreDNSVersion {
+			break
+		}
+	}
+	return cf.ToString(), nil
+}
+
+// MigrateDown returns the Corefile converted to toCoreDNSVersion, or an error if it cannot. This function only accepts
+// a downward migration, where the destination version is <= the start version.
+func MigrateDown(fromCoreDNSVersion, toCoreDNSVersion, corefileStr string) (string, error) {
+	if fromCoreDNSVersion == toCoreDNSVersion {
+		return corefileStr, nil
+	}
+	err := validDownMigration(fromCoreDNSVersion, toCoreDNSVersion)
+	if err != nil {
+		return "", err
+	}
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return "", err
+	}
+	v := fromCoreDNSVersion
+	for {
+		newSrvs := []*corefile.Server{}
+		for _, s := range cf.Servers {
+			newPlugs := []*corefile.Plugin{}
+			for _, p := range s.Plugins {
+				vp, present := Versions[v].plugins[p.Name]
+				if !present {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				if vp.downAction == nil {
+					newPlugs = append(newPlugs, p)
+					continue
+				}
+				p, err := vp.downAction(p)
+				if err != nil {
+					return "", err
+				}
+				if p == nil {
+					// remove plugin, skip options processing
+					continue
+				}
+
+				newOpts := []*corefile.Option{}
+				for _, o := range p.Options {
+					vo, present := Versions[v].plugins[p.Name].options[o.Name]
+					if !present {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					if vo.downAction == nil {
+						newOpts = append(newOpts, o)
+						continue
+					}
+					o, err := vo.downAction(o)
+					if err != nil {
+						return "", err
+					}
+					if o == nil {
+						// remove option
+						continue
+					}
+					newOpts = append(newOpts, o)
+				}
+				newPlug := &corefile.Plugin{
+					Name:    p.Name,
+					Args:    p.Args,
+					Options: newOpts,
+				}
+				newPlugs = append(newPlugs, newPlug)
+			}
+			newSrv := &corefile.Server{
+				DomPorts: s.DomPorts,
+				Plugins:  newPlugs,
+			}
+			newSrvs = append(newSrvs, newSrv)
+		}
+
+		cf = &corefile.Corefile{Servers: newSrvs}
+
+		if v == toCoreDNSVersion {
+			break
+		}
+		v = Versions[v].priorVersion
+	}
+	return cf.ToString(), nil
+}
+
+// Default returns true if the Corefile is the default for a given version of Kubernetes.
+// Or, if k8sVersion is empty, Default returns true if the Corefile is the default for any version of Kubernetes.
+func Default(k8sVersion, corefileStr string) bool {
+	cf, err := corefile.New(corefileStr)
+	if err != nil {
+		return false
+	}
+NextVersion:
+	for _, v := range Versions {
+		for _, release := range v.k8sReleases {
+			if k8sVersion != "" && k8sVersion != release {
+				continue
+			}
+		}
+		defCf, err := corefile.New(v.defaultConf)
+		if err != nil {
+			continue
+		}
+		// check corefile against k8s release default
+		if len(cf.Servers) != len(defCf.Servers) {
+			continue NextVersion
+		}
+		for _, s := range cf.Servers {
+			defS, found := s.FindMatch(defCf.Servers)
+			if !found {
+				continue NextVersion
+			}
+			if len(s.Plugins) != len(defS.Plugins) {
+				continue NextVersion
+			}
+			for _, p := range s.Plugins {
+				defP, found := p.FindMatch(defS.Plugins)
+				if !found {
+					continue NextVersion
+				}
+				if len(p.Options) != len(defP.Options) {
+					continue NextVersion
+				}
+				for _, o := range p.Options {
+					_, found := o.FindMatch(defP.Options)
+					if !found {
+						continue NextVersion
+					}
+				}
+			}
+		}
+		return true
+	}
+	return false
+}
+
+// Released returns true if dockerImageSHA matches any released image of CoreDNS.
+func Released(dockerImageSHA string) bool {
+	for _, v := range Versions {
+		if v.dockerImageSHA == dockerImageSHA {
+			return true
+		}
+	}
+	return false
+}
+
+// ValidVersions returns a list of all versions defined
+func ValidVersions() []string {
+	var vStrs []string
+	for vStr := range Versions {
+		vStrs = append(vStrs, vStr)
+	}
+	sort.Strings(vStrs)
+	return vStrs
+}
+
+func validateVersion(fromCoreDNSVersion string) error {
+	if _, ok := Versions[fromCoreDNSVersion]; !ok {
+		return fmt.Errorf("start version '%v' not supported", fromCoreDNSVersion)
+	}
+	return nil
+}
+
+func validUpMigration(fromCoreDNSVersion, toCoreDNSVersion string) error {
+	err := validateVersion(fromCoreDNSVersion)
+	if err != nil {
+		return err
+	}
+	for next := Versions[fromCoreDNSVersion].nextVersion; next != ""; next = Versions[next].nextVersion {
+		if next != toCoreDNSVersion {
+			continue
+		}
+		return nil
+	}
+	return fmt.Errorf("cannot migrate up to '%v' from '%v'", toCoreDNSVersion, fromCoreDNSVersion)
+}
+
+func validDownMigration(fromCoreDNSVersion, toCoreDNSVersion string) error {
+	err := validateVersion(fromCoreDNSVersion)
+	if err != nil {
+		return err
+	}
+	for prior := Versions[fromCoreDNSVersion].priorVersion; prior != ""; prior = Versions[prior].priorVersion {
+		if prior != toCoreDNSVersion {
+			continue
+		}
+		return nil
+	}
+	return fmt.Errorf("cannot migrate down to '%v' from '%v'", toCoreDNSVersion, fromCoreDNSVersion)
+}

vendor/github.com/coredns/corefile-migration/migration/notice.go

@@ -0,0 +1,48 @@
+package migration
+
+import "fmt"
+
+// Notice is a migration warning
+type Notice struct {
+	Plugin     string
+	Option     string
+	Severity   string // 'deprecated', 'removed', or 'unsupported'
+	ReplacedBy string
+	Additional string
+	Version    string
+}
+
+func (n *Notice) ToString() string {
+	s := ""
+	if n.Option == "" {
+		s += fmt.Sprintf(`Plugin "%v" `, n.Plugin)
+	} else {
+		s += fmt.Sprintf(`Option "%v" in plugin "%v" `, n.Option, n.Plugin)
+	}
+	if n.Severity == unsupported {
+		s += "is unsupported by this migration tool in " + n.Version + "."
+	} else if n.Severity == newdefault {
+		s += "is added as a default in " + n.Version + "."
+	} else {
+		s += "is " + n.Severity + " in " + n.Version + "."
+	}
+	if n.ReplacedBy != "" {
+		s += fmt.Sprintf(` It is replaced by "%v".`, n.ReplacedBy)
+	}
+	if n.Additional != "" {
+		s += " " + n.Additional
+	}
+	return s
+}
+
+const (
+	// The following statuses are used to indicate the state of support/deprecation in a given release.
+	deprecated  = "deprecated"  // deprecated, but still completely functional
+	ignored     = "ignored"     // if included in the corefile, it will be ignored by CoreDNS
+	removed     = "removed"     // completely removed from CoreDNS, and would cause CoreDNS to exit if present in the Corefile
+	newdefault  = "newdefault"  // added to the default corefile.  CoreDNS may not function properly if it is not present in the corefile.
+	unsupported = "unsupported" // the plugin/option is not supported by the migration tool
+
+	// The following statuses are used for selecting/filtering notifications
+	all = "all" // show all statuses
+)