provider: Add support for MX records

Author: thriqon

internal/designate/provider/provider.go

@@ -76,6 +76,22 @@ func canonicalizeDomainNames(domains []string) []string {
 	return cDomains
 }
 
+func canonicalizeDomainNamesForMX(domains []string) []string {
+	var cDomains []string
+
+	for _, d := range domains {
+		parts := strings.Split(d, " ")
+		if len(parts) == 2 {
+			// If the format does not conform to the expected one, play it safe and just pass the value on.
+			// Otherwise, canonicalize the hostname.
+			d = fmt.Sprintf("%s %s", parts[0], canonicalizeDomainName(parts[1]))
+		}
+
+		cDomains = append(cDomains, canonicalizeDomainName(d))
+	}
+	return cDomains
+}
+
 // converts domain name to FQDN
 func canonicalizeDomainName(d string) string {
 	if !strings.HasSuffix(d, ".") {
@@ -158,7 +174,7 @@ func (p designateProvider) Records(ctx context.Context) ([]*endpoint.Endpoint, e
 
 func (p designateProvider) supportedRecordType(recordType string) bool {
 	switch recordType {
-	case endpoint.RecordTypeA, endpoint.RecordTypeTXT, endpoint.RecordTypeCNAME, endpoint.RecordTypeNS:
+	case endpoint.RecordTypeA, endpoint.RecordTypeTXT, endpoint.RecordTypeCNAME, endpoint.RecordTypeNS, endpoint.RecordTypeMX:
 		return true
 	default:
 		return false
@@ -205,6 +221,9 @@ func addEndpoint(ep *endpoint.Endpoint, recordSets map[string]*recordSet, oldEnd
 	if ep.RecordType == endpoint.RecordTypeCNAME || ep.RecordType == endpoint.RecordTypeNS {
 		targets = canonicalizeDomainNames(targets)
 	}
+	if ep.RecordType == endpoint.RecordTypeMX {
+		targets = canonicalizeDomainNamesForMX(targets)
+	}
 	for _, t := range targets {
 		rs.names[t] = !delete
 	}

internal/designate/provider/provider_test.go

@@ -457,6 +457,12 @@ func testDesignateCreateRecords(t *testing.T, client *fakeDesignateClient) []*re
 			Targets:    endpoint.Targets{"ns1.test.net", "ns2.test.net", "ns3.test.net"},
 			Labels:     map[string]string{},
 		},
+		{
+			DNSName:    "mx.test.net",
+			RecordType: endpoint.RecordTypeMX,
+			Targets:    endpoint.Targets{"10 mx1.test.net", "100 mx2.test.net"},
+			Labels:     map[string]string{},
+		},
 	}
 	expected := []*recordsets.RecordSet{
 		{
@@ -496,6 +502,12 @@ func testDesignateCreateRecords(t *testing.T, client *fakeDesignateClient) []*re
 			Records: []string{"ns1.test.net.", "ns2.test.net.", "ns3.test.net."},
 			ZoneID:  "zone-2",
 		},
+		{
+			Name:    "mx.test.net.",
+			Type:    endpoint.RecordTypeMX,
+			Records: []string{"10 mx1.test.net.", "100 mx2.test.net."},
+			ZoneID:  "zone-2",
+		},
 	}
 	expectedCopy := make([]*recordsets.RecordSet, len(expected))
 	copy(expectedCopy, expected)