Future builder error, snapshot data empty - flutter

Question

Future builder is not working snapshot data is empty. I want build my catalog with gridview.builder, i think problem might be with my Product class.
And one more question, how to access objects inside the media class in json.
When i print my snapshot.data i got this:
flutter: null
this is my code:
late Future<List<Product>> productFuture = getProducts();
static Future<List<Product>> getProducts() async {
var url = '${Constants.API_URL_DOMAIN}action=catalog&category_id=$id';
final response = await http.get(Uri.parse(url));
print(url);
final body = jsonDecode(response.body);
return body['data'].map<Product>(Product.fromJson).toList();
}
this is my Product class:
class Product {
Product({
required this.id,
required this.name,
required this.categoryName,
required this.media,
});
late final int id;
late final String name;
late final String categoryName;
late final List<Media> media;
Product.fromJson(Map<String, dynamic> json){
id = json['id'];
name = json['name'];
categoryName = json['category_name'];
media = List.from(json['media']).map((e)=>Media.fromJson(e)).toList();
}
Map<String, dynamic> toJson() {
final _data = <String, dynamic>{};
_data['id'] = id;
_data['name'] = name;
_data['category_name'] = categoryName;
_data['media'] = media.map((e)=>e.toJson()).toList();
return _data;
}
}
class Media {
Media({
required this.id,
required this.productId,
required this.type,
required this.links,
required this.position,
required this.createdAt,
required this.updatedAt,
});
late final int id;
late final int productId;
late final String type;
late final Links links;
late final String position;
late final String createdAt;
late final String updatedAt;
Media.fromJson(Map<String, dynamic> json){
id = json['id'];
productId = json['product_id'];
type = json['type'];
links = Links.fromJson(json['links']);
position = json['position'];
createdAt = json['created_at'];
updatedAt = json['updated_at'];
}
Map<String, dynamic> toJson() {
final _data = <String, dynamic>{};
_data['id'] = id;
_data['product_id'] = productId;
_data['type'] = type;
_data['links'] = links.toJson();
_data['position'] = position;
_data['created_at'] = createdAt;
_data['updated_at'] = updatedAt;
return _data;
}
}
class Links {
Links({
required this.s3,
required this.cdn,
required this.local,
});
late final String s3;
late final String cdn;
late final Local local;
Links.fromJson(Map<String, dynamic> json){
s3 = json['s3'];
cdn = json['cdn'];
local = Local.fromJson(json['local']);
}
Map<String, dynamic> toJson() {
final _data = <String, dynamic>{};
_data['s3'] = s3;
_data['cdn'] = cdn;
_data['local'] = local.toJson();
return _data;
}
}
class Local {
Local({
required this.full,
required this.thumbnails,
});
late final String full;
late final Thumbnails thumbnails;
Local.fromJson(Map<String, dynamic> json){
full = json['full'];
thumbnails = Thumbnails.fromJson(json['thumbnails']);
}
Map<String, dynamic> toJson() {
final _data = <String, dynamic>{};
_data['full'] = full;
_data['thumbnails'] = thumbnails.toJson();
return _data;
}
}
class Thumbnails {
Thumbnails({
required this.s150,
required this.s350,
required this.s750,
});
late final String s150;
late final String s350;
late final String s750;
Thumbnails.fromJson(Map<String, dynamic> json){
s150 = json['150'];
s350 = json['350'];
s750 = json['750'];
}
Map<String, dynamic> toJson() {
final _data = <String, dynamic>{};
_data['150'] = s150;
_data['350'] = s350;
_data['750'] = s750;
return _data;
}
}
My FutureBuilder
FutureBuilder<List<Product>>(
future: productFuture,
builder: (context, snapshot) {
if (snapshot.connectionState == ConnectionState.waiting) {
return Center(child: CircularProgressIndicator());
} else if (snapshot.hasData) {
final catalog = snapshot.data;
return buildCatalog(catalog!);
} else {
print(snapshot.data);
return Text("No widget to build");
}
},
);