service: define and implement Token field composing interface

This commit:

  * defines SessionToken interface of Token field getters/setters group;

  * implements SessionToken on Token message.

service/token_test.go

@@ -0,0 +1,88 @@
+package service
+
+import (
+	"crypto/rand"
+	"testing"
+
+	"github.com/nspcc-dev/neofs-api-go/refs"
+	"github.com/stretchr/testify/require"
+)
+
+func TestTokenGettersSetters(t *testing.T) {
+	var tok SessionToken = new(Token)
+
+	{ // ID
+		id, err := refs.NewUUID()
+		require.NoError(t, err)
+
+		tok.SetID(id)
+
+		require.Equal(t, id, tok.GetID())
+	}
+
+	{ // OwnerID
+		ownerID := OwnerID{}
+		_, err := rand.Read(ownerID[:])
+		require.NoError(t, err)
+
+		tok.SetOwnerID(ownerID)
+
+		require.Equal(t, ownerID, tok.GetOwnerID())
+	}
+
+	{ // Verb
+		verb := Token_Info_Verb(3)
+
+		tok.SetVerb(verb)
+
+		require.Equal(t, verb, tok.GetVerb())
+	}
+
+	{ // Address
+		addr := Address{}
+		_, err := rand.Read(addr.CID[:])
+		require.NoError(t, err)
+		_, err = rand.Read(addr.ObjectID[:])
+		require.NoError(t, err)
+
+		tok.SetAddress(addr)
+
+		require.Equal(t, addr, tok.GetAddress())
+	}
+
+	{ // Created
+		e := uint64(5)
+
+		tok.SetCreationEpoch(e)
+
+		require.Equal(t, e, tok.CreationEpoch())
+	}
+
+	{ // ValidUntil
+		e := uint64(5)
+
+		tok.SetExpirationEpoch(e)
+
+		require.Equal(t, e, tok.ExpirationEpoch())
+	}
+
+	{ // SessionKey
+		key := make([]byte, 10)
+		_, err := rand.Read(key)
+		require.NoError(t, err)
+
+		tok.SetSessionKey(key)
+
+		require.Equal(t, key, tok.GetSessionKey())
+	}
+
+	{ // Signature
+		sig := make([]byte, 10)
+		_, err := rand.Read(sig)
+		require.NoError(t, err)
+
+		tok.SetSignature(sig)
+
+		require.Equal(t, sig, tok.GetSignature())
+	}
+}