(Delphi DLL) Google Drive Multipart Upload String

Demonstrates a file upload to Google Drive where the contents of the file are contained in a string variable.

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;
jsonResponse: PWideChar;

begin
// This example will upload a file to Google Drive.
success := True;

// It requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

gAuth := CkAuthGoogle_Create();
CkAuthGoogle_putScope(gAuth,'https://www.googleapis.com/auth/drive');
CkAuthGoogle_putSubEmailAddress(gAuth,'some.user@example.com');
CkAuthGoogle_putExpireNumSeconds(gAuth,3600);

// Obtain an access token as shown in one of the following examples:
// See Get Access Token using a Service Account JSON Key
// See Get Access Token using a P12 File

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 key)
success := CkRest_SetAuthGoogle(rest,gAuth);

// A multipart upload to Google Drive needs a multipart/related Content-Type
success := 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');
success := CkRest_AddHeader(rest,'Content-Type','application/json; charset=UTF-8');

json := CkJsonObject_Create();
success := CkJsonObject_AddStringAt(json,-1,'title','helloWorld.txt');
success := CkJsonObject_AddStringAt(json,-1,'description','A simple text file that says Hello World.');
success := CkJsonObject_AddStringAt(json,-1,'mimeType','text/plain');
success := 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');
success := CkRest_AddHeader(rest,'Content-Type','text/plain');
success := CkRest_SetMultipartBodyString(rest,'Hello World!');

// POST https://www.googleapis.com/upload/drive/v2/files
jsonResponse := CkRest__fullRequestMultipart(rest,'POST','/upload/drive/v2/files?uploadType=multipart');
if (CkRest_getLastMethodSuccess(rest) <> True) then
  begin
    Memo1.Lines.Add(CkRest__lastErrorText(rest));
    Exit;
  end;

// Show the JSON response.
Memo1.Lines.Add('Response Status Code: ' + IntToStr(CkRest_getResponseStatusCode(rest)));
Memo1.Lines.Add('Json Response: ' + jsonResponse);

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

end;