[#127] apistatus: Support WRONG_MAGIC_NUMBER status

Define `WrongMagicNumber` type for which encapsulates the work with
incorrect network magic. Provide method to read/write the correct magic
(which is a status detail in NeoFS API V2 protocol).

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

client/status/common.go

@@ -1,6 +1,8 @@
 package apistatus
 
 import (
+	"encoding/binary"
+
 	"github.com/nspcc-dev/neofs-api-go/v2/status"
 )
 
@@ -53,3 +55,71 @@ func (x ServerInternal) Message() string {
 func WriteInternalServerErr(x *ServerInternal, err error) {
 	x.SetMessage(err.Error())
 }
+
+// WrongMagicNumber describes failure status related to incorrect network magic.
+// Instances provide Status and StatusV2 interfaces.
+type WrongMagicNumber struct {
+	v2 status.Status
+}
+
+func (x WrongMagicNumber) Error() string {
+	return errMessageStatusV2(
+		globalizeCodeV2(status.WrongMagicNumber, status.GlobalizeCommonFail),
+		x.v2.Message(),
+	)
+}
+
+// implements method of the FromStatusV2 local interface.
+func (x *WrongMagicNumber) fromStatusV2(st *status.Status) {
+	x.v2 = *st
+}
+
+// ToStatusV2 implements StatusV2 interface method.
+// If the value was returned by FromStatusV2, returns the source message.
+// Otherwise, returns message with
+//  * code: WRONG_MAGIC_NUMBER;
+//  * string message: empty;
+//  * details: empty.
+func (x WrongMagicNumber) ToStatusV2() *status.Status {
+	x.v2.SetCode(globalizeCodeV2(status.WrongMagicNumber, status.GlobalizeCommonFail))
+	return &x.v2
+}
+
+// WriteCorrectMagic writes correct network magic.
+func (x *WrongMagicNumber) WriteCorrectMagic(magic uint64) {
+	// serialize the number
+	buf := make([]byte, 8)
+
+	binary.BigEndian.PutUint64(buf, magic)
+
+	// create corresponding detail
+	var d status.Detail
+
+	d.SetID(status.DetailIDCorrectMagic)
+	d.SetValue(buf)
+
+	// attach the detail
+	x.v2.AppendDetails(&d)
+}
+
+// CorrectMagic returns network magic returned by the server.
+// Second value indicates presence status:
+//   * -1 if number is presented in incorrect format
+//   * 0 if number is not presented
+//   * +1 otherwise
+func (x WrongMagicNumber) CorrectMagic() (magic uint64, ok int8) {
+	x.v2.IterateDetails(func(d *status.Detail) bool {
+		if d.ID() == status.DetailIDCorrectMagic {
+			if val := d.Value(); len(val) == 8 {
+				magic = binary.BigEndian.Uint64(val)
+				ok = 1
+			} else {
+				ok = -1
+			}
+		}
+
+		return ok != 0
+	})
+
+	return
+}

client/status/common_test.go

@@ -3,6 +3,7 @@ package apistatus_test
 import (
 	"testing"
 
+	"github.com/nspcc-dev/neofs-api-go/v2/status"
 	apistatus "github.com/nspcc-dev/neofs-sdk-go/client/status"
 	"github.com/stretchr/testify/require"
 )
@@ -24,3 +25,28 @@ func TestServerInternal_Message(t *testing.T) {
 	require.Equal(t, msg, res)
 	require.Equal(t, msg, resv2)
 }
+
+func TestWrongMagicNumber_CorrectMagic(t *testing.T) {
+	const magic = 1337
+
+	var st apistatus.WrongMagicNumber
+
+	res, ok := st.CorrectMagic()
+	require.Zero(t, res)
+	require.Zero(t, ok)
+
+	st.WriteCorrectMagic(magic)
+
+	res, ok = st.CorrectMagic()
+	require.EqualValues(t, magic, res)
+	require.EqualValues(t, 1, ok)
+
+	// corrupt the value
+	apistatus.ToStatusV2(st).IterateDetails(func(d *status.Detail) bool {
+		d.SetValue([]byte{1, 2, 3}) // any slice with len != 8
+		return true
+	})
+
+	_, ok = st.CorrectMagic()
+	require.EqualValues(t, -1, ok)
+}

client/status/v2.go

@@ -44,6 +44,8 @@ func FromStatusV2(st *status.Status) Status {
 		switch status.LocalizeCommonFail(&code); code {
 		case status.Internal:
 			decoder = new(ServerInternal)
+		case status.WrongMagicNumber:
+			decoder = new(WrongMagicNumber)
 		}
 	}
 

client/status/v2_test.go

@@ -49,6 +49,16 @@ func TestToStatusV2(t *testing.T) {
 			}),
 			codeV2: 1024,
 		},
+		{
+			status: (statusConstructor)(func() apistatus.Status {
+				var st apistatus.WrongMagicNumber
+
+				st.WriteCorrectMagic(322)
+
+				return st
+			}),
+			codeV2: 1025,
+		},
 	} {
 		var st apistatus.Status
 
@@ -117,6 +127,16 @@ func TestFromStatusV2(t *testing.T) {
 			}),
 			codeV2: 1024,
 		},
+		{
+			status: (statusConstructor)(func() apistatus.Status {
+				var st apistatus.WrongMagicNumber
+
+				st.WriteCorrectMagic(322)
+
+				return st
+			}),
+			codeV2: 1025,
+		},
 	} {
 		var st apistatus.Status
 

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/mr-tron/base58 v1.2.0
 	github.com/nspcc-dev/hrw v1.0.9
 	github.com/nspcc-dev/neo-go v0.98.0
-	github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220114101721-227a871a04ac
+	github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220127135316-32dd0bb3f9c5
 	github.com/nspcc-dev/neofs-crypto v0.3.0
 	github.com/stretchr/testify v1.7.0
 	go.uber.org/zap v1.18.1

go.sum

@@ -177,8 +177,8 @@ github.com/nspcc-dev/neo-go v0.73.1-pre.0.20200303142215-f5a1b928ce09/go.mod h1:
 github.com/nspcc-dev/neo-go v0.98.0 h1:yyW4sgY88/pLf0949qmgfkQXzRKC3CI/WyhqXNnwMd8=
 github.com/nspcc-dev/neo-go v0.98.0/go.mod h1:E3cc1x6RXSXrJb2nDWXTXjnXk3rIqVN8YdFyWv+FrqM=
 github.com/nspcc-dev/neofs-api-go/v2 v2.11.0-pre.0.20211201134523-3604d96f3fe1/go.mod h1:oS8dycEh8PPf2Jjp6+8dlwWyEv2Dy77h/XhhcdxYEFs=
-github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220114101721-227a871a04ac h1:65C4z7pybLT2HjtY96abZj6kbgVp34AbrApn5DD+ZxY=
-github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220114101721-227a871a04ac/go.mod h1:oS8dycEh8PPf2Jjp6+8dlwWyEv2Dy77h/XhhcdxYEFs=
+github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220127135316-32dd0bb3f9c5 h1:y9tbmUYhcr052QXsa4/IfUKAi2cx3TGDsEZUAow3P/Y=
+github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220127135316-32dd0bb3f9c5/go.mod h1:oS8dycEh8PPf2Jjp6+8dlwWyEv2Dy77h/XhhcdxYEFs=
 github.com/nspcc-dev/neofs-crypto v0.2.0/go.mod h1:F/96fUzPM3wR+UGsPi3faVNmFlA9KAEAUQR7dMxZmNA=
 github.com/nspcc-dev/neofs-crypto v0.2.3/go.mod h1:8w16GEJbH6791ktVqHN9YRNH3s9BEEKYxGhlFnp0cDw=
 github.com/nspcc-dev/neofs-crypto v0.3.0 h1:zlr3pgoxuzrmGCxc5W8dGVfA9Rro8diFvVnBg0L4ifM=