INWX: Guard against single-quote TXT targets (#971)

* INWX: split out and disable TXT with single-quote test
* INWX: add check for single-quotes in TXT records

integrationTest/integration_test.go

@@ -683,7 +683,10 @@ func makeTests(t *testing.T) []*TestGroup {
 			tc("Create 1 TXT as array", txtmulti("foo", []string{"simple"})), // Same as non-TXTMulti
 			clear(),
 			tc("Create a 255-byte TXT", txt("foo", strings.Repeat("A", 255))),
-			clear(),
+		),
+
+		testgroup("single TXT with single-quote",
+			not("INWX"),
 			tc("Create TXT with single-quote", txt("foo", "blah`blah")),
 		),
 

providers/inwx/inwxProvider.go

@@ -207,6 +207,18 @@ func (api *inwxAPI) deleteRecord(RecordID int) error {
 	return api.client.Nameservers.DeleteRecord(RecordID)
 }
 
+// checkRecords ensures that there is no single-quote inside TXT records which would be ignored by INWX.
+func checkRecords(records models.Records) error {
+	for _, r := range records {
+		if r.Type == "TXT" {
+			if strings.ContainsAny(r.Target, "`") {
+				return fmt.Errorf("INWX TXT records do not support single-quotes in their target")
+			}
+		}
+	}
+	return nil
+}
+
 // GetDomainCorrections finds the currently existing records and returns the corrections required to update them.
 func (api *inwxAPI) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Correction, error) {
 	dc.Punycode()
@@ -218,6 +230,11 @@ func (api *inwxAPI) GetDomainCorrections(dc *models.DomainConfig) ([]*models.Cor
 
 	models.PostProcessRecords(foundRecords)
 
+	err = checkRecords(dc.Records)
+	if err != nil {
+		return nil, err
+	}
+
 	differ := diff.New(dc)
 	_, create, del, mod, err := differ.IncrementalDiff(foundRecords)
 	if err != nil {