[Flutter] Getting categories in Flutter News Toolkit

While trying to retrieve categories from the categories endpoint, I have ran into this error: _TypeError (type 'List<dynamic>' is not a subtype of type 'Map<String, dynamic>' in type cast)

This error is thrown by the return in the extension from the myprojectname_api_client.dart:

Future<CategoriesResponse> getCategories() async {
final uri = Uri.parse('$_baseUrl/categories');
final response = await _httpClient.get(
uri,
headers: await _getRequestHeaders(),
);
final body = response.json();

if (response.statusCode != HttpStatus.ok) {
throw BernardinaiApiRequestFailure(
body: body,
statusCode: response.statusCode,
);
}

return CategoriesResponse.fromJson(body);
}

//------------

extension on http.Response {
Map<String, dynamic> json() {
try {
final decodedBody = utf8.decode(bodyBytes);
log("MyLog $body");
return jsonDecode(decodedBody) as Map<String, dynamic>;
} catch (error, stackTrace) {
Error.throwWithStackTrace(
BernardinaiApiMalformedResponse(error: error),
stackTrace,
);
}
}
}


The log shows that the decodeBody contains the full JSON from the categories endpoints.

The getCategories method in my custom class that implements NewsDataSource class looks like this:

Future<List<Category>> getCategories() async {
final uri = Uri.parse('https://www.mynewsurl.com/wp-json/wp/v2/categories');
final categoriesResponse = await http.get(uri);

if (categoriesResponse.statusCode == HttpStatus.ok) {
// Parse the response body into a Map
final Map<String, dynamic> categoriesData = jsonDecode(categoriesResponse.body) as Map<String, dynamic>;

// Access the 'categories' list from the map
final List<dynamic> categoriesList = categoriesData['categories'] as List<dynamic>;
log("MyLog categoriesList: $categoriesList");

// Extract category names and return them as a list of Category enums
final List<Category> categories = categoriesList.map((dynamic categoryData) {
final String categoryName = categoryData as String; // Explicitly cast to String
log("MyLog categoryName: $categoryName");

return Category.fromString(categoryName); // Use fromString to get the enum
}).toList();

log("MyLog categories to return: $categories");

return categories; // Returns list of category names
} else {
// Handle error cases by throwing a custom exception
throw BernardinaiApiRequestFailure(
statusCode: categoriesResponse.statusCode,
body: jsonDecode(categoriesResponse.body) as Map<String, dynamic>,
);
}
}

///------

class CategoriesInfo {
const CategoriesInfo(this.slug);

final String slug;

CategoriesInfo.fromJson(Map<String, dynamic> json)
: slug = _isKebabCase(json['slug'] as String)
? _convertToCamelCase(json['slug'] as String)
: json['slug'] as String;

Map<String, dynamic> toJson() {
log("mano as veikiu");
return {
'slug': slug,
};
}

static bool _isKebabCase(String input) {
log("MyLog checking what case is used");
return input.contains('-');
}

static String _convertToCamelCase(String input) {
log("MANO slugas: $input");
List<String> parts = input.split('-');
if (parts.length == 1) return input;

String camelCase = parts[0];
for (int i = 1; i < parts.length; i++) {
camelCase += parts[0].toUpperCase() + parts.substring(1);
}

return camelCase;
}
}


I tried to change the extension type to List, but then all the other methods are throwing the same error, so now I am wondering if the Future<List<Category>> getCategories() should not be a list but a map? But it was defined like that in the template, so maybe it's one of the bugs? Or perhaps I am not seeing something? I am completely lost and the documentation is of no help to me, so any help will be appreciated.

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