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Dart

PayPal Send Invoice Reminder

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Sends a PayPal invoice reminder to a customer.

Note: This example requires Chilkat v9.5.0.65 or greater.

Chilkat Dart Downloads

Dart
import 'package:chilkat/chilkat.dart';

void main() {
  // Note: Requires Chilkat v9.5.0.65 or greater.

  // This requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  // Load our previously obtained access token. (see PayPal OAuth2 Access Token)
  final jsonToken = CkJsonObject();
  jsonToken.loadFile('qa_data/tokens/paypal.json');

  // Build the Authorization request header field value.
  final sbAuth = CkStringBuilder();
  // token_type should be "Bearer"
  sbAuth.append(jsonToken.stringOf('token_type'));
  sbAuth.append(' ');
  sbAuth.append(jsonToken.stringOf('access_token'));

  // Make the initial connection.
  // A single REST object, once connected, can be used for many PayPal REST API calls.
  // The auto-reconnect indicates that if the already-established HTTPS connection is closed,
  // then it will be automatically re-established as needed.
  final rest = CkRest();
  final bAutoReconnect = true;
  try {
    rest.connect('api.sandbox.paypal.com', 443, true, bAutoReconnect);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // ----------------------------------------------------------------------------------------------
  // The code above this comment could be placed inside a function/subroutine within the application
  // because the connection does not need to be made for every request.  Once the connection is made
  // the app may send many requests..
  // ----------------------------------------------------------------------------------------------

  // Build the JSON request body containing the reminder information:
  final json = CkJsonObject();
  json.emitCompact = false;
  json.updateString('subject', 'Past due');
  json.updateString('note', 'Please pay soon');
  json.updateBool('send_to_merchant', true);
  print(json.emit());

  // The JSON created by the above code:

  // 	{ 
  // 	  "subject": "Past due",
  // 	  "note": "Please pay soon",
  // 	  "send_to_merchant": true,
  // 	}

  // Build a path using a previously-sent invoice ID.
  final sbPath = CkStringBuilder();
  sbPath.append('/v1/invoicing/invoices/invoice_id/remind');
  final numReplacements = sbPath.replace('invoice_id', 'INV2-ZG2H-HKAW-PMWU-N6ZR');

  json.emitCompact = true;
  final sbRequestBody = CkStringBuilder();
  final sbResponseBody = CkStringBuilder();

  rest.addHeader('Content-Type', 'application/json');
  rest.addHeader('Authorization', sbAuth.getAsString());
  json.emitSb(sbRequestBody);

  try {
    rest.fullRequestSb('POST', sbPath.getAsString(), sbRequestBody, sbResponseBody);
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  print('Response Status Code = ${rest.responseStatusCode}');

  // Did we get a 202 accepted response?
  if (rest.responseStatusCode != 202) {
    print(sbResponseBody.getAsString());
    print('Failed.');
    return;
  }

  // If the 202 response is received, the response body would be empty...
  print('Success.');
}