Future<PayPalAccessCredentials> obtainAccessCredentials()

Asynchronously obtains an access token from the PayPal API.

Source

Future<PayPalAccessCredentials> obtainAccessCredentials() async {
  var authString = BASE64.encode("$clientId:$clientSecret".codeUnits);
  var response = await post("$paypalEndpoint/oauth2/token",
      body: "grant_type=client_credentials",
      headers: {
        "Accept": "application/json",
        "Accept-Language": "en_US",
        "Authorization": "Basic $authString",
        "Content-Type": "application/x-www-form-urlencoded"
      });
  return new PayPalAccessCredentials.fromJson(response.body);
}