fetch static method

JSPromise fetch(dynamic input, [ dynamic init ])

Implementation

static JSPromise fetch(dynamic input, [dynamic init]) {
  String url = input?.toString() ?? '';
  String method = 'GET';
  Map<String, String> headers = {};
  dynamic body;

  if (init is Map) {
    if (init['method'] != null) method = init['method'].toString();
    if (init['headers'] is Map) {
      headers = Map<String, String>.fromEntries((init['headers'] as Map)
          .entries
          .map((e) => MapEntry(e.key.toString(), e.value.toString())));
    }
    if (init['body'] != null) {
      body = init['body'];
      if (body is Map) {
        body = jsonEncode(body);
        headers.putIfAbsent(
            'Content-Type', () => 'application/json; charset=utf-8');
      }
    }
  }

  Future<http.Response> fut;
  switch (method.toUpperCase()) {
    case 'POST':
      fut = http.post(Uri.parse(url), headers: headers, body: body);
      break;
    case 'PUT':
      fut = http.put(Uri.parse(url), headers: headers, body: body);
      break;
    case 'PATCH':
      fut = http.patch(Uri.parse(url), headers: headers, body: body);
      break;
    case 'DELETE':
      fut = http.delete(Uri.parse(url), headers: headers, body: body);
      break;
    default:
      fut = http.get(Uri.parse(url), headers: headers);
  }

  return JSPromise.fromFuture(
      fut.then((resp) => JSResponse(resp)).catchError((e) => throw e));
}