Pascal (Lazarus/Delphi)

Upload Application Specific Data

See more Google Drive Examples

Uploads a text file (application specific data) where the contents of the file are contained in a string variable. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.AuthGoogle,
  Chilkat.JsonObject,
  Chilkat.Rest;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  jsonToken: TJsonObject;
  gAuth: TAuthGoogle;
  rest: TRest;
  bAutoReconnect: Boolean;
  json: TJsonObject;
  fileContents: string;
  jsonResponse: string;

begin
  success := False;

  success := True;

  //  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 application specific data scope.
  jsonToken := TJsonObject.Create;
  success := jsonToken.LoadFile('qa_data/tokens/googleDriveAppData.json');

  gAuth := TAuthGoogle.Create;
  gAuth.AccessToken := jsonToken.StringOf('access_token');

  rest := TRest.Create;

  //  Connect using TLS.
  bAutoReconnect := True;
  success := 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');

  json := TJsonObject.Create;
  json.EmitCompact := False;

  json.UpdateString('name','helloWorld.txt');
  json.UpdateString('description','A simple text file that says Hello World.');
  json.UpdateString('mimeType','text/plain');
  //  Specifiy the application-specific data folder.
  json.UpdateString('parents[0]','appDataFolder');
  rest.SetMultipartBodyString(json.Emit());

  WriteLn(json.Emit());

  //  The JSON looks like this:
  //  {
  //    "name": "helloWorld.txt",
  //    "description": "A simple text file that says Hello World.",
  //    "mimeType": "text/plain",
  //    "parents": [
  //      "appDataFolder"
  //    ]
  //  }

  //  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');

  fileContents := 'Hello World!';
  rest.SetMultipartBodyString(fileContents);

  jsonResponse := rest.FullRequestMultipart('POST','/upload/drive/v3/files?uploadType=multipart');
  if (rest.LastMethodSuccess <> True) then
    begin
      WriteLn(rest.LastErrorText);
      Exit;
    end;

  //  A successful response will have a status code equal to 200.
  if (rest.ResponseStatusCode <> 200) then
    begin
      WriteLn('response status code = ' + rest.ResponseStatusCode);
      WriteLn('response status text = ' + rest.ResponseStatusText);
      WriteLn('response header: ' + rest.ResponseHeader);
      WriteLn('response JSON: ' + jsonResponse);
      Exit;
    end;

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

  //  Show the full JSON response.
  json.EmitCompact := False;
  WriteLn(json.Emit());

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

  //  Get the fileId:
  WriteLn('fileId: ' + json.StringOf('id'));


  jsonToken.Free;
  gAuth.Free;
  rest.Free;
  json.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.