getToken function
for getting access token
Implementation
Future getToken() async {
if (initializedClientID.isEmpty || initializedClientSecretKey.isEmpty) {
throw Exception(errk);
}
final data = {
'client_id': initializedClientID,
'client_secret': initializedClientSecretKey,
'scope': ApiKeys.scope,
'grant_type': ApiKeys.grantType,
};
final res = await http.post(Uri.parse(ApiKeys.tokenEndpoint), body: data);
accessToken = json.decode(res.body)['access_token'];
}