.

go/neo/client_test.go

@@ -52,6 +52,10 @@ type NEOSrv interface {
 	URL() string // zurl to access this NEO server
 
 	Bugs() []string // list of known server bugs
+
+	// BugEncFixed reports whether server, instead of autodetection,
+	// supports only fixed encoding, and, if yes, which one.
+	BugEncFixed() (bool, proto.Encoding)
 }
 
 // NEOSrvOptions represents options for a NEO server.
@@ -81,7 +85,11 @@ type NEOPySrv struct {
 }
 
 func (_ *NEOPySrv) Bugs() []string {
-	return []string{}
+	return []string{"encfixed"}
+}
+
+func (_ *NEOPySrv) BugEncFixed() (bool, proto.Encoding) {
+	return true, 'N' // NEO/py 1.12
 }
 
 // StartNEOPySrv starts NEO/py server specified by options.
@@ -209,6 +217,10 @@ func (_ *NEOGoSrv) Bugs() []string {
 	return []string{"nocommit"}
 }
 
+func (_ *NEOGoSrv) BugEncFixed() (bool, proto.Encoding) {
+	return false, 0 // NEO/go server autodetects client encoding
+}
+
 // StartNEOGoSrv starts NEO/go server specified by options.
 func StartNEOGoSrv(opt NEOSrvOptions) (_ *NEOGoSrv, err error) {
 	defer xerr.Contextf(&err, "start neo/go %s/%s", opt.workdir, opt.name)
@@ -537,7 +549,24 @@ func TestEncAutodetect(t *testing.T) {
 				neonet.DialEncTryOrder = encv
 				ndrv, _, err := neoOpen(nsrv.URL(),
 							&zodb.DriverOptions{ReadOnly: true}); X(err)
-				err = ndrv.Close(); X(err)
+				defer func() {
+					err := ndrv.Close(); X(err)
+				}()
+
+				// verify that link was established with either:
+				// - encv[0] encoding (NEO/go = server supports autodetection)
+				// - server encoding  (NEO/py)
+				encOK := encv[0]
+				noautodetect, srvEnc := nsrv.BugEncFixed()
+				if noautodetect {
+					encOK = srvEnc
+				}
+				mlink, err := ndrv.masterLink(context.Background()); X(err)
+
+				enc := mlink.Encoding()
+				if enc != encOK {
+					t.Fatalf("connected with encoding %c  ; want %c", enc, encOK)
+				}
 			})
 		}
 	})

go/neo/neonet/connection.go

@@ -166,6 +166,12 @@ type NodeLink struct {
 	rxghandoff chan struct{}
 }
 
+// Encoding returns protocol encoding with which the link was handshaked. XXX
+// XXX place
+func (nl *NodeLink) Encoding() proto.Encoding {
+	return nl.enc
+}
+
 // XXX rx handoff make latency better for serial request-reply scenario but
 // does a lot of harm for case when there are several parallel requests -
 // serveRecv after handing off is put to tail of current cpu runqueue - not