network: specify error message

For better user experience.

pkg/network/relay_reason.go

@@ -1,5 +1,7 @@
 package network
 
+//go:generate stringer -type=RelayReason -output=relay_reason_string.go
+
 // RelayReason is the type which describes the different relay outcome.
 type RelayReason uint8
 

pkg/network/relay_reason_string.go

@@ -0,0 +1,29 @@
+// Code generated by "stringer -type=RelayReason -output=relay_reason_string.go"; DO NOT EDIT.
+
+package network
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[RelaySucceed-0]
+	_ = x[RelayAlreadyExists-1]
+	_ = x[RelayOutOfMemory-2]
+	_ = x[RelayUnableToVerify-3]
+	_ = x[RelayInvalid-4]
+	_ = x[RelayPolicyFail-5]
+	_ = x[RelayUnknown-6]
+}
+
+const _RelayReason_name = "RelaySucceedRelayAlreadyExistsRelayOutOfMemoryRelayUnableToVerifyRelayInvalidRelayPolicyFailRelayUnknown"
+
+var _RelayReason_index = [...]uint8{0, 12, 30, 46, 65, 77, 92, 104}
+
+func (i RelayReason) String() string {
+	if i >= RelayReason(len(_RelayReason_index)-1) {
+		return "RelayReason(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _RelayReason_name[_RelayReason_index[i]:_RelayReason_index[i+1]]
+}

pkg/network/server.go

@@ -154,7 +154,7 @@ func newServerFromConstructors(config ServerConfig, chain blockchainer.Blockchai
 			n, err := notary.NewNotary(cfg, s.notaryRequestPool, func(tx *transaction.Transaction) error {
 				r := s.RelayTxn(tx)
 				if r != RelaySucceed {
-					return fmt.Errorf("can't pool notary tx: hash %s, reason: %d", tx.Hash().StringLE(), byte(r))
+					return fmt.Errorf("can't relay completed notary transaction: hash %s, reason: %s", tx.Hash().StringLE(), r.String())
 				}
 				return nil
 			})