Pascal (Lazarus/Delphi)

Upload Binary File from Memory

See more Google Drive Examples

This example demonstrates how to upload a binary file from memory. It uploads the file to a subdirectory of our choosing. 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.JsonArray,
  Chilkat.FileAccess,
  Chilkat.Rest,
  Chilkat.JsonObject,
  Chilkat.Cache;

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

procedure RunDemo;
var
  success: Boolean;
  gAuth: TAuthGoogle;
  rest: TRest;
  bAutoReconnect: Boolean;
  json: TJsonObject;
  gdCache: TCache;
  folderId: string;
  parents: TJsonArray;
  fac: TFileAccess;
  jpgBytes: TBytes;
  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.

  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','hedgehogs.jpg');
  json.AppendString('description','A cute photo of two hedgehogs.');
  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 Build Local Metadata Cache
  //  we built a local cache to make it easy to lookup file IDs given a file path.
  //  Let's find the file ID for the folder "testFolder/abc/123"
  gdCache := TCache.Create;
  gdCache.Level := 0;
  gdCache.AddRoot('C:/ckCache/googleDrive');

  folderId := gdCache.FetchText('testFolder/abc/123');
  if (gdCache.LastMethodSuccess <> True) then
    begin
      WriteLn('Filepath not found in cache.');
      Exit;
    end;

  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');

  fac := TFileAccess.Create;

  //  Read a JPG file from the local filesystem.
  jpgBytes := fac.ReadEntireFile('qa_data/jpg/hedgehogs.jpg');

  //  Add the bytes to our upload
  rest.SetMultipartBodyBinary(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;

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

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


  gAuth.Free;
  rest.Free;
  json.Free;
  gdCache.Free;
  parents.Free;
  fac.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.