Pascal (Lazarus/Delphi)

Google Drive - Upload File

See more Google Drive Examples

This example demonstrates how to upload a file to Google Drive. The assumption is that the file can be loaded into memory and uploaded. It is also possible to stream large files to Google Drive, but the code required is a little more complex. 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.JsonArray,
  Chilkat.BinData,
  Chilkat.AuthGoogle,
  Chilkat.JsonObject,
  Chilkat.Rest;

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

procedure RunDemo;
var
  success: Boolean;
  gAuth: TAuthGoogle;
  rest: TRest;
  bAutoReconnect: Boolean;
  json: TJsonObject;
  folderId: string;
  parents: TJsonArray;
  jpgBytes: TBinData;
  jsonResponse: string;

begin
  success := False;

  success := True;

  //  This example 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. 
  //  See Get Google Drive OAuth2 Access Token

  gAuth := TAuthGoogle.Create;
  gAuth.AccessToken := 'GOOGLE_DRIVE_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');

  //  Construct the JSON that will contain the metadata about the file data to be uploaded...
  json := TJsonObject.Create;
  json.AppendString('name','starfish.jpg');
  json.AppendString('description','A picture of a starfish.');
  json.AppendString('mimeType','image/jpeg');

  //  To place the file in a folder, we must add a parents[] array to the JSON
  //  and add the folder ID.  
  //  In a previous example (see Lookup Google Drive Folder ID
  //  we showed how to find the folder ID for a folder in Google Drive.

  //  Use the folder ID we already looked up..
  folderId := '1Fksv-TfA1ILii1YjXsNa1-rDu8Cdrg72';

  parents := TJsonArray.Create;
  json.AppendArray2('parents',parents);

  parents.AddStringAt(-1,folderId);

  rest.SetMultipartBodyString(json.Emit());

  //  The 2nd part is the file content, which will contain the binary image data.
  rest.PartSelector := '2';
  rest.AddHeader('Content-Type','image/jpeg');

  jpgBytes := TBinData.Create;
  success := jpgBytes.LoadFile('qa_data/jpg/starfish.jpg');

  //  Add the data to our upload
  rest.SetMultipartBodyBd(jpgBytes);

  jsonResponse := rest.FullRequestMultipart('POST','/upload/drive/v3/files?uploadType=multipart');
  if (rest.LastMethodSuccess = False) 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;

  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": "starfish.jpg",
  //    "mimeType": "image/jpeg"
  //  }

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


  gAuth.Free;
  rest.Free;
  json.Free;
  parents.Free;
  jpgBytes.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.