getRankings method
Gets all the rankings.
Implementation
Future<List<Ranking>> getRankings() async {
final response = await _context.client.get(
Uri.https(authority, '$path/rankings'),
);
ClientException.checkIsSuccessStatusCode(response);
return (json.decode(response.body) as List)
.map((e) => Ranking.fromJson(e))
.toList();
}