dump and load

etcd.go

@@ -98,7 +98,28 @@ func (e *etcd) ReadPrefix(prefix string) (Prefix, error) {
 
 	return fromJSON(get.Kvs[0].Value)
 }
-func (e *etcd) ReadAllPrefixes() ([]Prefix, error) {
+
+func (e *etcd) DeleteAllPrefixes() error {
+	e.lock.RLock()
+	defer e.lock.RUnlock()
+	ctx, cancel := context.WithTimeout(context.Background(), 50*time.Minute)
+	defaultOpts := []clientv3.OpOption{clientv3.WithPrefix(), clientv3.WithKeysOnly(), clientv3.WithSerializable()}
+	pfxs, err := e.etcdDB.Get(ctx, "", defaultOpts...)
+	defer cancel()
+	if err != nil {
+		return fmt.Errorf("unable to get all prefix cidrs:%w", err)
+	}
+
+	for _, pfx := range pfxs.Kvs {
+		_, err := e.etcdDB.Delete(ctx, string(pfx.Key))
+		if err != nil {
+			return fmt.Errorf("unable to delete prefix:%w", err)
+		}
+	}
+	return nil
+}
+
+func (e *etcd) ReadAllPrefixes() (Prefixes, error) {
 	e.lock.Lock()
 	defer e.lock.Unlock()
 
@@ -110,7 +131,7 @@ func (e *etcd) ReadAllPrefixes() ([]Prefix, error) {
 		return nil, fmt.Errorf("unable to get all prefix cidrs:%w", err)
 	}
 
-	result := []Prefix{}
+	result := Prefixes{}
 	for _, pfx := range pfxs.Kvs {
 		v, err := e.etcdDB.Get(ctx, string(pfx.Key))
 		if err != nil {

go.mod

@@ -3,15 +3,15 @@ module github.com/metal-stack/go-ipam
 go 1.18
 
 require (
-	github.com/avast/retry-go/v4 v4.0.5
+	github.com/avast/retry-go/v4 v4.1.0
 	github.com/go-redis/redis/v8 v8.11.5
 	github.com/jmoiron/sqlx v1.3.5
 	github.com/lib/pq v1.10.6
-	github.com/stretchr/testify v1.7.1
+	github.com/stretchr/testify v1.7.2
 	github.com/testcontainers/testcontainers-go v0.13.0
 	go.etcd.io/etcd/client/v3 v3.5.4
-	golang.org/x/sync v0.0.0-20220513210516-0976fa681c29
-	inet.af/netaddr v0.0.0-20211027220019-c74959edd3b6
+	golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f
+	inet.af/netaddr v0.0.0-20220617031823-097006376321
 )
 
 require (
@@ -52,12 +52,12 @@ require (
 	go.uber.org/multierr v1.6.0 // indirect
 	go.uber.org/zap v1.17.0 // indirect
 	go4.org/intern v0.0.0-20220301175310-a089fc204883 // indirect
-	go4.org/unsafe/assume-no-moving-gc v0.0.0-20211027215541-db492cf91b37 // indirect
+	go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760 // indirect
 	golang.org/x/net v0.0.0-20220516155154-20f960328961 // indirect
 	golang.org/x/sys v0.0.0-20220513210249-45d2b4557a2a // indirect
 	golang.org/x/text v0.3.7 // indirect
 	google.golang.org/genproto v0.0.0-20220505152158-f39f71e6c8f3 // indirect
 	google.golang.org/grpc v1.46.2 // indirect
 	google.golang.org/protobuf v1.28.0 // indirect
-	gopkg.in/yaml.v3 v3.0.0-20220512140231-539c8e751b99 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -78,8 +78,8 @@ github.com/alexflint/go-filemutex v0.0.0-20171022225611-72bdc8eae2ae/go.mod h1:C
 github.com/antihax/optional v1.0.0/go.mod h1:uupD/76wgC+ih3iEmQUL+0Ugr19nfwCT1kdvxnR2qWY=
 github.com/armon/consul-api v0.0.0-20180202201655-eb2c6b5be1b6/go.mod h1:grANhF5doyWs3UAsr3K4I6qtAmlQcZDesFNEHPZAzj8=
 github.com/asaskevich/govalidator v0.0.0-20190424111038-f61b66f89f4a/go.mod h1:lB+ZfQJz7igIIfQNfa7Ml4HSf2uFQQRzpGGRXenZAgY=
-github.com/avast/retry-go/v4 v4.0.5 h1:C0Fm9MjPCmgLW6Jb1zBTVRx0ycr+VUaaUZO5wpqYjqg=
-github.com/avast/retry-go/v4 v4.0.5/go.mod h1:HqmLvS2VLdStPCGDFjSuZ9pzlTqVRldCI4w2dO4m1Ms=
+github.com/avast/retry-go/v4 v4.1.0 h1:CwudD9anYv6JMVnDuTRlK6kLo4dBamiL+F3U8YDiyfg=
+github.com/avast/retry-go/v4 v4.1.0/go.mod h1:HqmLvS2VLdStPCGDFjSuZ9pzlTqVRldCI4w2dO4m1Ms=
 github.com/aws/aws-sdk-go v1.15.11/go.mod h1:mFuSZ37Z9YOHbQEwBWztmVzqXrEkub65tZoCYDt7FT0=
 github.com/beorn7/perks v0.0.0-20160804104726-4c0e84591b9a/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
 github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
@@ -685,8 +685,8 @@ github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81P
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
-github.com/stretchr/testify v1.7.1 h1:5TQK59W5E3v0r2duFAb7P95B6hEeOyEnHRa8MjYSMTY=
-github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.7.2 h1:4jaiDzPyXQvSd7D0EjG45355tLlV3VOECpq10pLC+8s=
+github.com/stretchr/testify v1.7.2/go.mod h1:R6va5+xMeoiuVRoj+gSkQ7d3FALtqAAGI1FQKckRals=
 github.com/syndtr/gocapability v0.0.0-20170704070218-db04d3cc01c8/go.mod h1:hkRG7XYTFWNJGYcbNJQlaLq0fg1yr4J4t/NcTQtrfww=
 github.com/syndtr/gocapability v0.0.0-20180916011248-d98352740cb2/go.mod h1:hkRG7XYTFWNJGYcbNJQlaLq0fg1yr4J4t/NcTQtrfww=
 github.com/syndtr/gocapability v0.0.0-20200815063812-42c35b437635/go.mod h1:hkRG7XYTFWNJGYcbNJQlaLq0fg1yr4J4t/NcTQtrfww=
@@ -753,8 +753,9 @@ go.uber.org/zap v1.17.0/go.mod h1:MXVU+bhUf/A7Xi2HNOnopQOrmycQ5Ih87HtOu4q5SSo=
 go4.org/intern v0.0.0-20211027215823-ae77deb06f29/go.mod h1:cS2ma+47FKrLPdXFpr7CuxiTW3eyJbWew4qx0qtQWDA=
 go4.org/intern v0.0.0-20220301175310-a089fc204883 h1:pq5gAii+wMY+DsJ5r9I6T7CHjHxHlb4d45gChzX2SsI=
 go4.org/intern v0.0.0-20220301175310-a089fc204883/go.mod h1:cS2ma+47FKrLPdXFpr7CuxiTW3eyJbWew4qx0qtQWDA=
-go4.org/unsafe/assume-no-moving-gc v0.0.0-20211027215541-db492cf91b37 h1:Tx9kY6yUkLge/pFG7IEMwDZy6CS2ajFc9TvQdPCW0uA=
 go4.org/unsafe/assume-no-moving-gc v0.0.0-20211027215541-db492cf91b37/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
+go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760 h1:FyBZqvoA/jbNzuAWLQE2kG820zMAkcilx6BMjGbL/E4=
+go4.org/unsafe/assume-no-moving-gc v0.0.0-20220617031537-928513b29760/go.mod h1:FftLjUGFEDu5k8lt0ddY+HcrH/qU/0qk+H8j9/nTl3E=
 golang.org/x/crypto v0.0.0-20171113213409-9f005a07e0d3/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20181009213950-7c1a557ab941/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
@@ -860,8 +861,8 @@ golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJ
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20220513210516-0976fa681c29 h1:w8s32wxx3sY+OjLlv9qltkLU5yvJzxjjgiHWLjdIcw4=
-golang.org/x/sync v0.0.0-20220513210516-0976fa681c29/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f h1:Ax0t5p6N38Ga0dThY21weqDEyz2oklo4IvDkpigvkD8=
+golang.org/x/sync v0.0.0-20220601150217-0de741cfad7f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
@@ -1131,8 +1132,8 @@ gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
 gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
 gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
-gopkg.in/yaml.v3 v3.0.0-20220512140231-539c8e751b99 h1:dbuHpmKjkDzSOMKAWl10QNlgaZUd3V1q99xc81tt2Kc=
-gopkg.in/yaml.v3 v3.0.0-20220512140231-539c8e751b99/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gotest.tools v2.2.0+incompatible h1:VsBPFP1AI068pPrMxtb/S8Zkgf9xEmTLJjfM+P5UIEo=
 gotest.tools v2.2.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
 gotest.tools/gotestsum v1.7.0/go.mod h1:V1m4Jw3eBerhI/A6qCxUE07RnCg7ACkKj9BYcAm09V8=
@@ -1145,8 +1146,8 @@ honnef.co/go/tools v0.0.0-20190418001031-e561f6794a2a/go.mod h1:rf3lG4BRIbNafJWh
 honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
 honnef.co/go/tools v0.0.1-2020.1.3/go.mod h1:X/FiERA/W4tHapMX5mGpAtMSVEeEUOyHaw9vFzvIQ3k=
-inet.af/netaddr v0.0.0-20211027220019-c74959edd3b6 h1:acCzuUSQ79tGsM/O50VRFySfMm19IoMKL+sZztZkCxw=
-inet.af/netaddr v0.0.0-20211027220019-c74959edd3b6/go.mod h1:y3MGhcFMlh0KZPMuXXow8mpjxxAk3yoDNsp4cQz54i8=
+inet.af/netaddr v0.0.0-20220617031823-097006376321 h1:B4dC8ySKTQXasnjDTMsoCMf1sQG4WsMej0WXaHxunmU=
+inet.af/netaddr v0.0.0-20220617031823-097006376321/go.mod h1:OIezDfdzOgFhuw4HuWapWq2e9l0H9tK4F1j+ETRtF3k=
 k8s.io/api v0.20.1/go.mod h1:KqwcCVogGxQY3nBlRpwt+wpAMF/KjaCc7RpywacvqUo=
 k8s.io/api v0.20.4/go.mod h1:++lNL1AJMkDymriNniQsWRkMDzRaX2Y/POTUi8yvqYQ=
 k8s.io/api v0.20.6/go.mod h1:X9e8Qag6JV/bL5G6bU8sdVRltWKmdHsFUGS3eVndqE8=

ipam.go

@@ -32,6 +32,10 @@ type Ipamer interface {
 	// PrefixesOverlapping will check if one ore more prefix of newPrefixes is overlapping
 	// with one of existingPrefixes
 	PrefixesOverlapping(existingPrefixes []string, newPrefixes []string) error
+	// Dump all stored prefixes as json formatted string
+	Dump() (string, error)
+	// Load a previously created json formatted dump, deletes all prefixes before loading
+	Load(dump string) error
 	// ReadAllPrefixCidrs retrieves all existing Prefix CIDRs from the underlying storage
 	ReadAllPrefixCidrs() ([]string, error)
 }

json.go

@@ -55,6 +55,18 @@ func (p Prefix) toJSON() ([]byte, error) {
 	return pj, nil
 }
 
+func (ps Prefixes) toJSON() ([]byte, error) {
+	var pfxjs []prefixJSON
+	for _, p := range ps {
+		pfxjs = append(pfxjs, p.toPrefixJSON())
+	}
+	pj, err := json.Marshal(pfxjs)
+	if err != nil {
+		return nil, fmt.Errorf("unable to marshal prefixes:%w", err)
+	}
+	return pj, nil
+}
+
 func fromJSON(js []byte) (Prefix, error) {
 	var pre prefixJSON
 	err := json.Unmarshal(js, &pre)
@@ -63,3 +75,16 @@ func fromJSON(js []byte) (Prefix, error) {
 	}
 	return pre.toPrefix(), nil
 }
+
+func fromJSONs(js []byte) (Prefixes, error) {
+	var pres []prefixJSON
+	err := json.Unmarshal(js, &pres)
+	if err != nil {
+		return Prefixes{}, fmt.Errorf("unable to unmarshal prefixes:%w", err)
+	}
+	var pfxs Prefixes
+	for _, pj := range pres {
+		pfxs = append(pfxs, pj.toPrefix())
+	}
+	return pfxs, nil
+}

json_test.go

@@ -0,0 +1,59 @@
+package ipam
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestPrefixes_JSON(t *testing.T) {
+
+	p1 := Prefix{
+		Cidr:                   "192.168.0.0/24",
+		ParentCidr:             "192.168.0.0/20",
+		isParent:               false,
+		availableChildPrefixes: map[string]bool{},
+		childPrefixLength:      0,
+		ips:                    map[string]bool{"192.168.0.1": true, "192.168.0.2": true},
+		version:                0,
+	}
+
+	p2 := Prefix{
+		Cidr:                   "172.17.0.0/24",
+		ParentCidr:             "172.17.0.0/20",
+		isParent:               false,
+		availableChildPrefixes: map[string]bool{},
+		childPrefixLength:      0,
+		ips:                    map[string]bool{"172.17.0.1": true, "172.17.0.2": true},
+		version:                0,
+	}
+
+	p1j, err := p1.toJSON()
+	require.NoError(t, err)
+	require.NotNil(t, p1j)
+	p2j, err := p2.toJSON()
+	require.NoError(t, err)
+	require.NotNil(t, p1j)
+
+	p1reverse, err := fromJSON(p1j)
+	require.NoError(t, err)
+	require.NotNil(t, p1reverse)
+	require.Equal(t, p1, p1reverse)
+
+	p2reverse, err := fromJSON(p2j)
+	require.NoError(t, err)
+	require.NotNil(t, p2reverse)
+	require.Equal(t, p2, p2reverse)
+
+	ps1 := Prefixes{p1, p2}
+
+	ps1j, err := ps1.toJSON()
+	require.NoError(t, err)
+	require.NotNil(t, ps1j)
+
+	ps1reverse, err := fromJSONs(ps1j)
+	require.NoError(t, err)
+	require.NotNil(t, ps1reverse)
+	require.Equal(t, ps1, ps1reverse)
+
+}

memory.go

@@ -40,11 +40,17 @@ func (m *memory) ReadPrefix(prefix string) (Prefix, error) {
 	}
 	return *result.deepCopy(), nil
 }
-func (m *memory) ReadAllPrefixes() ([]Prefix, error) {
+func (m *memory) DeleteAllPrefixes() error {
+	m.lock.RLock()
+	defer m.lock.RUnlock()
+	m.prefixes = make(map[string]Prefix)
+	return nil
+}
+func (m *memory) ReadAllPrefixes() (Prefixes, error) {
 	m.lock.RLock()
 	defer m.lock.RUnlock()
 
-	ps := make([]Prefix, 0, len(m.prefixes))
+	ps := make(Prefixes, 0, len(m.prefixes))
 	for _, v := range m.prefixes {
 		ps = append(ps, *v.deepCopy())
 	}

prefix.go

@@ -36,6 +36,8 @@ type Prefix struct {
 	version           int64           // version is used for optimistic locking
 }
 
+type Prefixes []Prefix
+
 // deepCopy to a new Prefix
 func (p Prefix) deepCopy() *Prefix {
 	return &Prefix{
@@ -128,7 +130,7 @@ type Usage struct {
 	// AvailableIPs the number of available IPs if this is not a parent prefix
 	// No more than 2^31 available IPs are reported
 	AvailableIPs uint64
-	// AcquiredIPs the number of acquire IPs if this is not a parent prefix
+	// AcquiredIPs the number of acquired IPs if this is not a parent prefix
 	AcquiredIPs uint64
 	// AvailableSmallestPrefixes is the count of available Prefixes with 2 countable Bits
 	// No more than 2^31 available Prefixes are reported
@@ -484,6 +486,43 @@ func (i *ipamer) newPrefix(cidr, parentCidr string) (*Prefix, error) {
 	return p, nil
 }
 
+func (i *ipamer) Dump() (string, error) {
+	pfxs, err := i.storage.ReadAllPrefixes()
+	if err != nil {
+		return "", err
+	}
+	js, err := pfxs.toJSON()
+	if err != nil {
+		return "", err
+	}
+	return string(js), nil
+}
+
+func (i *ipamer) Load(dump string) error {
+	existingpfxs, err := i.storage.ReadAllPrefixes()
+	if err != nil {
+		return err
+	}
+	if len(existingpfxs) > 0 {
+		return fmt.Errorf("prefixes exist, please drop existing data before loading")
+	}
+	pfxs, err := fromJSONs([]byte(dump))
+	if err != nil {
+		return err
+	}
+	err = i.storage.DeleteAllPrefixes()
+	if err != nil {
+		return err
+	}
+	for _, pfx := range pfxs {
+		_, err = i.storage.CreatePrefix(pfx)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 // ReadAllPrefixCidrs retrieves all existing Prefix CIDRs from the underlying storage
 func (i *ipamer) ReadAllPrefixCidrs() ([]string, error) {
 	return i.storage.ReadAllPrefixCidrs()

prefix_test.go

@@ -2,14 +2,13 @@ package ipam
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"reflect"
 	"strings"
 	"sync"
 	"testing"
 
-	"errors"
-
 	"github.com/stretchr/testify/require"
 	"golang.org/x/sync/errgroup"
 	"inet.af/netaddr"
@@ -318,7 +317,7 @@ func TestIpamer_AcquireIPCountsIPv4(t *testing.T) {
 		prefix, err := ipam.NewPrefix("192.168.0.0/24")
 		require.Nil(t, err)
 		require.Equal(t, prefix.availableips(), uint64(256))
-		// network an broadcast are blocked
+		// network and broadcast are blocked
 		require.Equal(t, prefix.acquiredips(), uint64(2))
 		ip1, err := ipam.AcquireIP(prefix.Cidr)
 		require.Nil(t, err)
@@ -1457,6 +1456,33 @@ func TestAcquireIPParallel(t *testing.T) {
 	})
 }
 
+func Test_ipamer_DumpAndLoad(t *testing.T) {
+
+	testWithBackends(t, func(t *testing.T, ipam *ipamer) {
+		prefix, err := ipam.NewPrefix("192.168.0.0/24")
+		require.Nil(t, err)
+		require.NotNil(t, prefix)
+
+		data, err := ipam.Dump()
+		require.Nil(t, err)
+		require.NotEmpty(t, data)
+
+		t.Log(data)
+
+		err = ipam.Load(data)
+		require.Error(t, err)
+		require.Equal(t, "prefixes exist, please drop existing data before loading", err.Error())
+
+		err = ipam.storage.DeleteAllPrefixes()
+		require.NoError(t, err)
+		err = ipam.Load(data)
+		require.NoError(t, err)
+
+		newPrefix := ipam.PrefixFrom(prefix.Cidr)
+
+		require.Equal(t, prefix, newPrefix)
+	})
+}
 func TestIpamer_ReadAllPrefixCidrs(t *testing.T) {
 
 	testWithBackends(t, func(t *testing.T, ipam *ipamer) {