[#119] client: Configure network magic

In the latest NeoFS protocol update, each request is provided with a
network magic number. We have to provide the ability to set it on
the client.

Add `WithNetworkMagic` option constructor which accepts magic number.
Write the number to meta header of the all requests.

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

client/opts.go

@@ -27,6 +27,9 @@ type (
 		key      *ecdsa.PrivateKey
 		session  *session.Token
 		bearer   *token.BearerToken
+		// network magic is a client config, but it's convenient to copy it here (see v2MetaHeaderFromOpts)
+		// the value remains the same between calls
+		netMagic uint64
 	}
 
 	clientOptions struct {
@@ -41,6 +44,8 @@ type (
 		//
 		// default is false
 		parseNeoFSErrors bool
+
+		netMagic uint64
 	}
 
 	v2SessionReqInfo struct {
@@ -56,6 +61,8 @@ func (c *Client) defaultCallOptions() *callOptions {
 		version: version.Current(),
 		ttl:     2,
 		key:     c.opts.key,
+		// copy client's static value is a bit overhead, but it is the easiest way at the time of feature intro
+		netMagic: c.opts.netMagic,
 	}
 }
 
@@ -115,6 +122,8 @@ func v2MetaHeaderFromOpts(options *callOptions) *v2session.RequestMetaHeader {
 
 	meta.SetSessionToken(options.session.ToV2())
 
+	meta.SetNetworkMagic(options.netMagic)
+
 	return meta
 }
 
@@ -210,3 +219,10 @@ func WithNeoFSErrorParsing() Option {
 		opts.parseNeoFSErrors = true
 	}
 }
+
+// WithNetworkMagic returns option to specify NeoFS network magic.
+func WithNetworkMagic(magic uint64) Option {
+	return func(opts *clientOptions) {
+		opts.netMagic = magic
+	}
+}

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 v2.11.1
+	github.com/nspcc-dev/neofs-api-go/v2 v2.11.2-0.20220114101721-227a871a04ac
 	github.com/nspcc-dev/neofs-crypto v0.3.0
 	github.com/stretchr/testify v1.7.0
 	go.uber.org/zap v1.18.1