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Dart

Upload File from String

See more Google Drive Examples

Uploads a text file where the contents of the file are contained in a string variable.

See Google Drive Files: create for more details.

Also See Google Drive Multipart Upload for more details.

Chilkat Dart Downloads

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

void main() {
  // It requires the Chilkat API to have been previously unlocked.
  // See Global Unlock Sample for sample code.

  // This example uses a previously obtained access token having permission for the 
  // Google Drive scope.

  final gAuth = CkAuthGoogle();
  gAuth.accessToken = 'GOOGLE-DRIVE-ACCESS-TOKEN';

  final rest = CkRest();

  // Connect using TLS.
  final bAutoReconnect = true;
  rest.connect('www.googleapis.com', 443, true, bAutoReconnect);

  // Provide the authentication credentials (i.e. the access token)
  rest.setAuthGoogle(gAuth);

  // A multipart upload to Google Drive needs a multipart/related Content-Type
  rest.addHeader('Content-Type', 'multipart/related');

  // Specify each part of the request.

  // The 1st part is JSON with information about the file.
  rest.partSelector = '1';
  rest.addHeader('Content-Type', 'application/json; charset=UTF-8');

  final json = CkJsonObject();
  json.appendString('name', 'helloWorld.txt');
  json.appendString('description', 'A simple text file that says Hello World.');
  json.appendString('mimeType', 'text/plain');
  rest.setMultipartBodyString(json.emit());

  // The 2nd part is the file content.
  // In this case, we'll upload a simple text file containing "Hello World!"
  rest.partSelector = '2';
  rest.addHeader('Content-Type', 'text/plain');

  final fileContents = 'Hello World!';
  rest.setMultipartBodyString(fileContents);

  final String jsonResponse;
  try {
    jsonResponse = rest.fullRequestMultipart('POST', '/upload/drive/v3/files?uploadType=multipart');
  } on ChilkatException catch (e) {
    print(e.lastErrorText);
    return;
  }

  // A successful response will have a status code equal to 200.
  if (rest.responseStatusCode != 200) {
    print('response status code = ${rest.responseStatusCode}');
    print('response status text = ${rest.responseStatusText}');
    print('response header: ${rest.responseHeader}');
    print('response JSON: $jsonResponse');
    return;
  }

  // Show the JSON response.
  json.load(jsonResponse);

  // Show the full JSON response.
  json.emitCompact = false;
  print(json.emit());

  // A successful response looks like this:
  // {
  //   "kind": "drive#file",
  //   "id": "0B53Q6OSTWYoldmJ0Z3ZqT2x5MFk",
  //   "name": "Untitled",
  //   "mimeType": "text/plain"
  // }

  // Get the fileId:
  print('fileId: ${json.stringOf('id')}');
}