fix(dns): keep comments intact with zero values of UpdateDNSRecordParams

.changelog/1393.txt

@@ -0,0 +1,3 @@
+```release-note:bug
+dns: keep comments when calling UpdateDNSRecord with zero values of UpdateDNSRecordParams
+```

dns.go

@@ -34,7 +34,7 @@ type DNSRecord struct {
 	Proxied    *bool       `json:"proxied,omitempty"`
 	Proxiable  bool        `json:"proxiable,omitempty"`
 	Locked     bool        `json:"locked,omitempty"`
-	Comment    string      `json:"comment,omitempty"`
+	Comment    string      `json:"comment,omitempty"` // the server will omit the comment field when the comment is empty
 	Tags       []string    `json:"tags,omitempty"`
 }
 
@@ -57,8 +57,8 @@ type ListDNSRecordsParams struct {
 	Name      string        `url:"name,omitempty"`
 	Content   string        `url:"content,omitempty"`
 	Proxied   *bool         `url:"proxied,omitempty"`
-	Comment   string        `url:"comment,omitempty"`
-	Tags      []string      `url:"tag,omitempty"` // potentially multiple `tag=`
+	Comment   string        `url:"comment,omitempty"` // currently, the server does not support searching for records with an empty comment
+	Tags      []string      `url:"tag,omitempty"`     // potentially multiple `tag=`
 	TagMatch  string        `url:"tag-match,omitempty"`
 	Order     string        `url:"order,omitempty"`
 	Direction ListDirection `url:"direction,omitempty"`
@@ -77,7 +77,7 @@ type UpdateDNSRecordParams struct {
 	Priority *uint16     `json:"priority,omitempty"`
 	TTL      int         `json:"ttl,omitempty"`
 	Proxied  *bool       `json:"proxied,omitempty"`
-	Comment  string      `json:"comment"`
+	Comment  *string     `json:"comment,omitempty"` // nil will keep the current comment, while StringPtr("") will empty it
 	Tags     []string    `json:"tags"`
 }
 
@@ -193,7 +193,7 @@ type CreateDNSRecordParams struct {
 	Proxied    *bool       `json:"proxied,omitempty" url:"proxied,omitempty"`
 	Proxiable  bool        `json:"proxiable,omitempty"`
 	Locked     bool        `json:"locked,omitempty"`
-	Comment    string      `json:"comment,omitempty" url:"comment,omitempty"`
+	Comment    string      `json:"comment,omitempty" url:"comment,omitempty"` // to the server, there's no difference between "no comment" and "empty comment"
 	Tags       []string    `json:"tags,omitempty"`
 }
 

dns_test.go

@@ -616,7 +616,63 @@ func TestUpdateDNSRecord_ClearComment(t *testing.T) {
 
 	_, err := client.UpdateDNSRecord(context.Background(), ZoneIdentifier(testZoneID), UpdateDNSRecordParams{
 		ID:      dnsRecordID,
-		Comment: "",
+		Comment: StringPtr(""),
+	})
+	require.NoError(t, err)
+}
+
+func TestUpdateDNSRecord_KeepComment(t *testing.T) {
+	setup()
+	defer teardown()
+
+	input := DNSRecord{
+		ID: "372e67954025e0ba6aaa6d586b9e0b59",
+	}
+
+	handler := func(w http.ResponseWriter, r *http.Request) {
+		assert.Equal(t, http.MethodPatch, r.Method, "Expected method 'PATCH', got %s", r.Method)
+
+		var v DNSRecord
+		err := json.NewDecoder(r.Body).Decode(&v)
+		require.NoError(t, err)
+		v.ID = "372e67954025e0ba6aaa6d586b9e0b59"
+		assert.Equal(t, input, v)
+
+		w.Header().Set("content-type", "application/json")
+		fmt.Fprint(w, `{
+			"success": true,
+			"errors": [],
+			"messages": [],
+			"result": {
+				"id": "372e67954025e0ba6aaa6d586b9e0b59",
+				"type": "A",
+				"name": "example.com",
+				"content": "198.51.100.4",
+				"proxiable": true,
+				"proxied": false,
+				"ttl": 120,
+				"locked": false,
+				"zone_id": "d56084adb405e0b7e32c52321bf07be6",
+				"zone_name": "example.com",
+				"created_on": "2014-01-01T05:20:00Z",
+				"modified_on": "2014-01-01T05:20:00Z",
+				"comment":null,
+				"tags":[],
+				"data": {},
+				"meta": {
+					"auto_added": true,
+					"source": "primary"
+				}
+			}
+		}`)
+	}
+
+	dnsRecordID := "372e67954025e0ba6aaa6d586b9e0b59"
+
+	mux.HandleFunc("/zones/"+testZoneID+"/dns_records/"+dnsRecordID, handler)
+
+	_, err := client.UpdateDNSRecord(context.Background(), ZoneIdentifier(testZoneID), UpdateDNSRecordParams{
+		ID: dnsRecordID,
 	})
 	require.NoError(t, err)
 }