Pascal (Lazarus/Delphi)

Search for Files in Google Drive

See more Google Drive Examples

This example follows the same methodology for listing all files in Google Drive in pages, but applies a search filter. It shows how to apply a query parameter for filtering the file results. See the Google Drive Files list for more optional HTTP parameters. 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;
  gAuth: TAuthGoogle;
  rest: TRest;
  bAutoReconnect: Boolean;
  json: TJsonObject;
  i: Integer;
  numFiles: Integer;
  jsonResponse: string;
  pageNumber: Integer;
  pageToken: string;
  bContinueLoop: Boolean;
  bHasMorePages: Boolean;

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 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);

  //  Get 5 results per page for testing.  (The default page size is 100, with a max of 1000.
  rest.AddQueryParam('pageSize','5');

  //  Our search filter is to list all files containing ".jpg" (i.e. all JPG image files)
  rest.AddQueryParam('q','name contains ''.jpg''');

  json := TJsonObject.Create;

  //  Send the request for the 1st page.
  jsonResponse := rest.FullRequestNoBody('GET','/drive/v3/files');

  pageNumber := 1;

  bContinueLoop := rest.LastMethodSuccess and (rest.ResponseStatusCode = 200);

  while bContinueLoop = True do
    begin

      WriteLn('---- Page ' + pageNumber + ' ----');

      //  Iterate over each file in the response and show the name, id, and mimeType.
      json.Load(jsonResponse);

      numFiles := json.SizeOfArray('files');
      i := 0;
      while i < numFiles do
        begin
          json.I := i;
          WriteLn('name: ' + json.StringOf('files[i].name'));
          WriteLn('id: ' + json.StringOf('files[i].id'));
          WriteLn('mimeType: ' + json.StringOf('files[i].mimeType'));
          WriteLn('-');
          i := i + 1;
        end;

      //  Get the next page of files.
      //  If the "nextPageToken" is present in the JSON response, then use it in the "pageToken" parameter
      //  for the next request.   If no "nextPageToken" was present, then this was the last page of files.
      pageToken := json.StringOf('nextPageToken');
      bContinueLoop := False;
      bHasMorePages := json.LastMethodSuccess;
      if (bHasMorePages = True) then
        begin
          rest.ClearAllQueryParams();
          rest.AddQueryParam('pageSize','5');
          rest.AddQueryParam('pageToken',pageToken);
          rest.AddQueryParam('q','name contains ''.jpg''');

          jsonResponse := rest.FullRequestNoBody('GET','/drive/v3/files');
          bContinueLoop := rest.LastMethodSuccess and (rest.ResponseStatusCode = 200);
          pageNumber := pageNumber + 1;
        end;

    end;

  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;


  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.