(Delphi DLL) Search for Files in Google Drive

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.

Chilkat for Delphi Downloads Chilkat non-ActiveX DLL for Delphi Chilkat ActiveX DLL for Delphi * The examples here use the non-ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, AuthGoogle, JsonObject, Rest;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
gAuth: HCkAuthGoogle;
rest: HCkRest;
bAutoReconnect: Boolean;
json: HCkJsonObject;
i: Integer;
numFiles: Integer;
jsonResponse: PWideChar;
pageNumber: Integer;
pageToken: PWideChar;
bContinueLoop: Boolean;
bHasMorePages: Boolean;

begin
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 := CkAuthGoogle_Create();
CkAuthGoogle_putAccessToken(gAuth,'GOOGLE-DRIVE-ACCESS-TOKEN');

rest := CkRest_Create();

// Connect using TLS.
bAutoReconnect := True;
success := CkRest_Connect(rest,'www.googleapis.com',443,True,bAutoReconnect);

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

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

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

json := CkJsonObject_Create();

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

pageNumber := 1;

bContinueLoop := CkRest_getLastMethodSuccess(rest) and (CkRest_getResponseStatusCode(rest) = 200);

while bContinueLoop = True do
  begin

    Memo1.Lines.Add('---- Page ' + IntToStr(pageNumber) + ' ----');

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

    numFiles := CkJsonObject_SizeOfArray(json,'files');
    i := 0;
    while i < numFiles do
      begin
        CkJsonObject_putI(json,i);
        Memo1.Lines.Add('name: ' + CkJsonObject__stringOf(json,'files[i].name'));
        Memo1.Lines.Add('id: ' + CkJsonObject__stringOf(json,'files[i].id'));
        Memo1.Lines.Add('mimeType: ' + CkJsonObject__stringOf(json,'files[i].mimeType'));
        Memo1.Lines.Add('-');
        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 := CkJsonObject__stringOf(json,'nextPageToken');
    bContinueLoop := False;
    bHasMorePages := CkJsonObject_getLastMethodSuccess(json);
    if (bHasMorePages = True) then
      begin
        CkRest_ClearAllQueryParams(rest);
        CkRest_AddQueryParam(rest,'pageSize','5');
        CkRest_AddQueryParam(rest,'pageToken',pageToken);
        CkRest_AddQueryParam(rest,'q','name contains ''.jpg''');

        jsonResponse := CkRest__fullRequestNoBody(rest,'GET','/drive/v3/files');
        bContinueLoop := CkRest_getLastMethodSuccess(rest) and (CkRest_getResponseStatusCode(rest) = 200);
        pageNumber := pageNumber + 1;
      end;

  end;

if (CkRest_getLastMethodSuccess(rest) <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

// A successful response will have a status code equal to 200.
if (CkRest_getResponseStatusCode(rest) <> 200) then
  begin
    Memo1.Lines.Add('response status code = ' + IntToStr(CkRest_getResponseStatusCode(rest)));
    Memo1.Lines.Add('response status text = ' + CkRest__responseStatusText(rest));
    Memo1.Lines.Add('response header: ' + CkRest__responseHeader(rest));
    Memo1.Lines.Add('response JSON: ' + jsonResponse);
    Exit;
  end;

CkAuthGoogle_Dispose(gAuth);
CkRest_Dispose(rest);
CkJsonObject_Dispose(json);

end;