(Delphi DLL) Upload File from String

Uploads a text file where the contents of the file are contained in a string variable.

See Google Drive Files: create for more details.

Also See Google Drive Multipart Upload for more details.

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;
fileContents: PWideChar;
jsonResponse: PWideChar;

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);

// A multipart upload to Google Drive needs a multipart/related Content-Type
CkRest_AddHeader(rest,'Content-Type','multipart/related');

// Specify each part of the request.

// The 1st part is JSON with information about the file.
CkRest_putPartSelector(rest,'1');
CkRest_AddHeader(rest,'Content-Type','application/json; charset=UTF-8');

json := CkJsonObject_Create();
CkJsonObject_AppendString(json,'name','helloWorld.txt');
CkJsonObject_AppendString(json,'description','A simple text file that says Hello World.');
CkJsonObject_AppendString(json,'mimeType','text/plain');
CkRest_SetMultipartBodyString(rest,CkJsonObject__emit(json));

// The 2nd part is the file content.
// In this case, we'll upload a simple text file containing "Hello World!"
CkRest_putPartSelector(rest,'2');
CkRest_AddHeader(rest,'Content-Type','text/plain');

fileContents := 'Hello World!';
CkRest_SetMultipartBodyString(rest,fileContents);

jsonResponse := CkRest__fullRequestMultipart(rest,'POST','/upload/drive/v3/files?uploadType=multipart');
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;

// Show the JSON response.
CkJsonObject_Load(json,jsonResponse);

// Show the full JSON response.
CkJsonObject_putEmitCompact(json,False);
Memo1.Lines.Add(CkJsonObject__emit(json));

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

// Get the fileId:
Memo1.Lines.Add('fileId: ' + CkJsonObject__stringOf(json,'id'));

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

end;