refactor: factorize referral retrieval

Author: james-d-elliott

modify.go

@@ -161,18 +161,7 @@ func (l *Conn) ModifyWithResult(modifyRequest *ModifyRequest) (*ModifyResult, er
 	case ApplicationModifyResponse:
 		err := GetLDAPError(packet)
 		if err != nil {
-			if IsErrorWithCode(err, LDAPResultReferral) && len(packet.Children) >= 2 {
-				for _, child := range packet.Children[1].Children {
-					if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
-						referral, ok := child.Children[0].Value.(string)
-						if ok {
-							result.Referral = referral
-
-							break
-						}
-					}
-				}
-			}
+			result.Referral = getReferral(err, packet)
 
 			return result, err
 		}

passwdmodify.go

@@ -97,18 +97,7 @@ func (l *Conn) PasswordModify(passwordModifyRequest *PasswordModifyRequest) (*Pa
 	if packet.Children[1].Tag == ApplicationExtendedResponse {
 		err := GetLDAPError(packet)
 		if err != nil {
-			if IsErrorWithCode(err, LDAPResultReferral) && len(packet.Children) >= 2 {
-				for _, child := range packet.Children[1].Children {
-					if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
-						referral, ok := child.Children[0].Value.(string)
-						if ok {
-							result.Referral = referral
-
-							break
-						}
-					}
-				}
-			}
+			result.Referral = getReferral(err, packet)
 
 			return result, err
 		}

request.go

@@ -69,3 +69,21 @@ func (l *Conn) readPacket(msgCtx *messageContext) (*ber.Packet, error) {
 	}
 	return packet, nil
 }
+
+func getReferral(err error, packet *ber.Packet) (referral string) {
+	var ok bool
+
+	if !IsErrorWithCode(err, LDAPResultReferral) || len(packet.Children) < 2 {
+		return ""
+	}
+
+	for _, child := range packet.Children[1].Children {
+		if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
+			if referral, ok = child.Children[0].Value.(string); ok {
+				return referral
+			}
+		}
+	}
+
+	return ""
+}

v3/modify.go

@@ -161,18 +161,7 @@ func (l *Conn) ModifyWithResult(modifyRequest *ModifyRequest) (*ModifyResult, er
 	case ApplicationModifyResponse:
 		err := GetLDAPError(packet)
 		if err != nil {
-			if IsErrorWithCode(err, LDAPResultReferral) && len(packet.Children) >= 2 {
-				for _, child := range packet.Children[1].Children {
-					if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
-						referral, ok := child.Children[0].Value.(string)
-						if ok {
-							result.Referral = referral
-
-							break
-						}
-					}
-				}
-			}
+			result.Referral = getReferral(err, packet)
 
 			return result, err
 		}

v3/passwdmodify.go

@@ -97,18 +97,7 @@ func (l *Conn) PasswordModify(passwordModifyRequest *PasswordModifyRequest) (*Pa
 	if packet.Children[1].Tag == ApplicationExtendedResponse {
 		err := GetLDAPError(packet)
 		if err != nil {
-			if IsErrorWithCode(err, LDAPResultReferral) && len(packet.Children) >= 2 {
-				for _, child := range packet.Children[1].Children {
-					if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
-						referral, ok := child.Children[0].Value.(string)
-						if ok {
-							result.Referral = referral
-
-							break
-						}
-					}
-				}
-			}
+			result.Referral = getReferral(err, packet)
 
 			return result, err
 		}

v3/request.go

@@ -69,3 +69,21 @@ func (l *Conn) readPacket(msgCtx *messageContext) (*ber.Packet, error) {
 	}
 	return packet, nil
 }
+
+func getReferral(err error, packet *ber.Packet) (referral string) {
+	var ok bool
+
+	if !IsErrorWithCode(err, LDAPResultReferral) || len(packet.Children) < 2 {
+		return ""
+	}
+
+	for _, child := range packet.Children[1].Children {
+		if child.Tag == ber.TagBitString && len(child.Children) >= 1 {
+			if referral, ok = child.Children[0].Value.(string); ok {
+				return referral
+			}
+		}
+	}
+
+	return ""
+}