Unknown rtypes should not result in panic (StackExchange#2775)

commands/getZones.go

@@ -286,8 +286,12 @@ func GetZone(args GetZoneArgs) error {
 					}
 				}
 
+				ty := rec.Type
+				if rec.Type == "UNKNOWN" {
+					ty = rec.UnknownTypeName
+				}
 				fmt.Fprintf(w, "%s\t%s\t%d\tIN\t%s\t%s%s\n",
-					rec.NameFQDN, rec.Name, rec.TTL, rec.Type, rec.GetTargetCombinedFunc(nil), cfproxy)
+					rec.NameFQDN, rec.Name, rec.TTL, ty, rec.GetTargetCombinedFunc(nil), cfproxy)
 			}
 
 		default:
@@ -363,6 +367,8 @@ func formatDsl(zonename string, rec *models.RecordConfig, defaultTTL uint32) str
 		target = `"` + target + `"`
 	case "R53_ALIAS":
 		return makeR53alias(rec, ttl)
+	case "UNKNOWN":
+		return makeUknown(rec, ttl)
 	default:
 		target = `"` + target + `"`
 	}
@@ -399,3 +405,7 @@ func makeR53alias(rec *models.RecordConfig, ttl uint32) string {
 	}
 	return rec.Type + "(" + strings.Join(items, ", ") + ")"
 }
+
+func makeUknown(rc *models.RecordConfig, ttl uint32) string {
+	return fmt.Sprintf(`// %s("%s")`, rc.UnknownTypeName, rc.GetTargetField())
+}

models/record.go

@@ -93,7 +93,7 @@ type RecordConfig struct {
 	Metadata  map[string]string `json:"meta,omitempty"`
 	Original  interface{}       `json:"-"` // Store pointer to provider-specific record object. Used in diffing.
 
-	// If you add a field to this struct, also add it to the list on MarshalJSON.
+	// If you add a field to this struct, also add it to the list in the UnmarshalJSON function.
 	MxPreference     uint16            `json:"mxpreference,omitempty"`
 	SrvPriority      uint16            `json:"srvpriority,omitempty"`
 	SrvWeight        uint16            `json:"srvweight,omitempty"`
@@ -129,6 +129,7 @@ type RecordConfig struct {
 	TlsaMatchingType uint8             `json:"tlsamatchingtype,omitempty"`
 	R53Alias         map[string]string `json:"r53_alias,omitempty"`
 	AzureAlias       map[string]string `json:"azure_alias,omitempty"`
+	UnknownTypeName  string            `json:"unknown_type_name,omitempty"`
 }
 
 // MarshalJSON marshals RecordConfig.
@@ -196,6 +197,7 @@ func (rc *RecordConfig) UnmarshalJSON(b []byte) error {
 		TlsaMatchingType uint8             `json:"tlsamatchingtype,omitempty"`
 		R53Alias         map[string]string `json:"r53_alias,omitempty"`
 		AzureAlias       map[string]string `json:"azure_alias,omitempty"`
+		UnknownTypeName  string            `json:"unknown_type_name,omitempty"`
 
 		EnsureAbsent bool `json:"ensure_absent,omitempty"` // Override NO_PURGE and delete this record
 
@@ -318,6 +320,8 @@ func (rc *RecordConfig) ToComparableNoTTL() string {
 		r := txtutil.EncodeQuoted(rc.target)
 		//fmt.Fprintf(os.Stdout, "DEBUG: ToComNoTTL cmp txts=%s q=%q\n", r, r)
 		return r
+	case "UNKNOWN":
+		return fmt.Sprintf("rtype=%s rdata=%s", rc.UnknownTypeName, rc.target)
 	}
 	return rc.GetTargetCombined()
 }

models/t_parse.go

@@ -104,8 +104,8 @@ func (rc *RecordConfig) PopulateFromStringFunc(rtype, contents, origin string, t
 	case "TLSA":
 		return rc.SetTargetTLSAString(contents)
 	default:
-		return fmt.Errorf("unknown rtype (%s) when parsing (%s) domain=(%s)",
-			rtype, contents, origin)
+		//return fmt.Errorf("unknown rtype (%s) when parsing (%s) domain=(%s)", rtype, contents, origin)
+		return MakeUnknown(rc, rtype, contents, origin)
 	}
 }
 

models/target.go

@@ -45,6 +45,7 @@ func (rc *RecordConfig) GetTargetCombinedFunc(encodeFn func(s string) string) st
 // WARNING: How TXT records are handled is buggy but we can't change it because
 // code depends on the bugs. Use Get GetTargetCombinedFunc() instead.
 func (rc *RecordConfig) GetTargetCombined() string {
+
 	// Pseudo records:
 	if _, ok := dns.StringToType[rc.Type]; !ok {
 		switch rc.Type { // #rtype_variations
@@ -60,7 +61,10 @@ func (rc *RecordConfig) GetTargetCombined() string {
 		}
 	}
 
+	// Everything else
 	switch rc.Type {
+	case "UNKNOWN":
+		return fmt.Sprintf("rtype=%s rdata=%s", rc.UnknownTypeName, rc.target)
 	case "TXT":
 		return rc.zoneFileQuoted()
 	case "SOA":

models/unknown.go

@@ -0,0 +1,9 @@
+package models
+
+func MakeUnknown(rc *RecordConfig, rtype string, contents string, origin string) error {
+	rc.Type = "UNKNOWN"
+	rc.UnknownTypeName = rtype
+	rc.target = contents
+
+	return nil
+}

pkg/prettyzone/prettyzone.go

@@ -137,6 +137,9 @@ func (z *ZoneGenData) generateZoneFileHelper(w io.Writer) error {
 
 		// type
 		typeStr := rr.Type
+		if rr.Type == "UNKNOWN" {
+			typeStr = rr.UnknownTypeName
+		}
 
 		// the remaining line
 		target := rr.GetTargetCombinedFunc(txtutil.EncodeQuoted)