From 4dd6accb5cee05ff1f975dab7965a0dbe1caafd9 Mon Sep 17 00:00:00 2001
From: Alex Wilcox <alex.wilcox@cloudsecure.ltd>
Date: Fri, 20 Dec 2024 01:27:16 +0000
Subject: [PATCH] Add update function

---
 internal/services/dns/dns_zone_resource.go | 101 ++++++++++++++++++---
 1 file changed, 88 insertions(+), 13 deletions(-)

diff --git a/internal/services/dns/dns_zone_resource.go b/internal/services/dns/dns_zone_resource.go
index f85fd608c3e8..a24c1ae49639 100644
--- a/internal/services/dns/dns_zone_resource.go
+++ b/internal/services/dns/dns_zone_resource.go
@@ -23,7 +23,6 @@ import (
 )
 
 var (
-	_ sdk.Resource                   = DnsZoneResource{}
 	_ sdk.ResourceWithUpdate         = DnsZoneResource{}
 	_ sdk.ResourceWithStateMigration = DnsZoneResource{}
 )
@@ -194,26 +193,24 @@ func (r DnsZoneResource) Create() sdk.ResourceFunc {
 			}
 
 			id := zones.NewDnsZoneID(subscriptionId, model.ResourceGroupName, model.Name)
-			if metadata.ResourceData.IsNewResource() {
-				existing, err := client.Get(ctx, id)
-				if err != nil {
-					if !response.WasNotFound(existing.HttpResponse) {
-						return fmt.Errorf("checking for presence of existing %s: %+v", id, err)
-					}
-				}
-
+			existing, err := client.Get(ctx, id)
+			if err != nil {
 				if !response.WasNotFound(existing.HttpResponse) {
-					return metadata.ResourceRequiresImport(r.ResourceType(), id)
+					return fmt.Errorf("checking for presence of existing %s: %+v", id, err)
 				}
 			}
 
+			if !response.WasNotFound(existing.HttpResponse) {
+				return metadata.ResourceRequiresImport(r.ResourceType(), id)
+			}
+
 			parameters := zones.Zone{
 				Location: location.Normalize("global"),
 				Tags:     pointer.To(model.Tags),
 			}
 
 			if _, err := client.CreateOrUpdate(ctx, id, parameters, zones.DefaultCreateOrUpdateOperationOptions()); err != nil {
-				return fmt.Errorf("creating/updating %s: %+v", id, err)
+				return fmt.Errorf("creating %s: %+v", id, err)
 			}
 
 			if len(model.SoaRecord) == 1 {
@@ -246,7 +243,7 @@ func (r DnsZoneResource) Create() sdk.ResourceFunc {
 
 				soaRecordId := recordsets.NewRecordTypeID(id.SubscriptionId, id.ResourceGroupName, id.DnsZoneName, recordsets.RecordTypeSOA, "@")
 				if _, err := recordSetsClient.CreateOrUpdate(ctx, soaRecordId, rsParameters, recordsets.DefaultCreateOrUpdateOperationOptions()); err != nil {
-					return fmt.Errorf("creating/updating %s: %+v", soaRecordId, err)
+					return fmt.Errorf("creating %s: %+v", soaRecordId, err)
 				}
 			}
 
@@ -305,7 +302,85 @@ func (DnsZoneResource) Read() sdk.ResourceFunc {
 }
 
 func (r DnsZoneResource) Update() sdk.ResourceFunc {
-	return r.Create()
+	return sdk.ResourceFunc{
+		Timeout: 30 * time.Minute,
+		Func: func(ctx context.Context, metadata sdk.ResourceMetaData) error {
+			client := metadata.Client.Dns.Zones
+			recordSetsClient := metadata.Client.Dns.RecordSets
+
+			var model DnsZoneResourceModel
+			if err := metadata.Decode(&model); err != nil {
+				return fmt.Errorf("decoding: %+v", err)
+			}
+
+			id, err := zones.ParseDnsZoneID(metadata.ResourceData.Id())
+			if err != nil {
+				return err
+			}
+
+			existing, err := client.Get(ctx, *id)
+			if err != nil {
+				return fmt.Errorf("retrieving %s: %+v", *id, err)
+			}
+
+			if existing.Model == nil {
+				return fmt.Errorf("retrieving %s: `model` was nil", id)
+			}
+
+			if existing.Model.Properties == nil {
+				return fmt.Errorf("retrieving %s: `properties` was nil", id)
+			}
+
+			payload := zones.Zone{
+				Location: existing.Model.Location,
+				Tags:     existing.Model.Tags,
+			}
+
+			if metadata.ResourceData.HasChange("tags") {
+				payload.Tags = pointer.To(model.Tags)
+			}
+
+			if _, err := client.CreateOrUpdate(ctx, *id, payload, zones.DefaultCreateOrUpdateOperationOptions()); err != nil {
+				return fmt.Errorf("updating %s: %+v", id, err)
+			}
+
+			if metadata.ResourceData.HasChange("soa_record") && len(model.SoaRecord) == 1 {
+				soaRecordID := recordsets.NewRecordTypeID(id.SubscriptionId, id.ResourceGroupName, id.DnsZoneName, recordsets.RecordTypeSOA, "@")
+				soaRecordResp, err := recordSetsClient.Get(ctx, soaRecordID)
+				if err != nil {
+					return fmt.Errorf("retrieving %s to update SOA: %+v", id, err)
+				}
+
+				props := soaRecordResp.Model.Properties
+				if props == nil || props.SOARecord == nil {
+					return fmt.Errorf("could not read SOA properties for %s", id)
+				}
+
+				inputSOARecord := expandDNSZoneSOARecord(model.SoaRecord[0])
+
+				inputSOARecord.Host = props.SOARecord.Host
+
+				rsParameters := recordsets.RecordSet{
+					Properties: &recordsets.RecordSetProperties{
+						TTL:       pointer.To(model.SoaRecord[0].Ttl),
+						Metadata:  pointer.To(model.SoaRecord[0].Tags),
+						SOARecord: inputSOARecord,
+					},
+				}
+
+				if len(id.DnsZoneName+strings.TrimSuffix(*rsParameters.Properties.SOARecord.Email, ".")) > 253 {
+					return fmt.Errorf("`email` which is concatenated with DNS Zone `name` cannot exceed 253 characters excluding a trailing period")
+				}
+
+				soaRecordId := recordsets.NewRecordTypeID(id.SubscriptionId, id.ResourceGroupName, id.DnsZoneName, recordsets.RecordTypeSOA, "@")
+				if _, err := recordSetsClient.CreateOrUpdate(ctx, soaRecordId, rsParameters, recordsets.DefaultCreateOrUpdateOperationOptions()); err != nil {
+					return fmt.Errorf("updating %s: %+v", soaRecordId, err)
+				}
+			}
+
+			return nil
+		},
+	}
 }
 
 func (r DnsZoneResource) Delete() sdk.ResourceFunc {