(Delphi DLL) Download a Specific GMail Message into a Chilkat Email Object

Demonstrates how to download a GMail message into a Chilkat Email object.

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, Http, StringBuilder, Email, JsonObject;

...

procedure TForm1.Button1Click(Sender: TObject);
var
success: Boolean;
http: HCkHttp;
id: PWideChar;
userId: PWideChar;
url: PWideChar;
sbJson: HCkStringBuilder;
json: HCkJsonObject;
sbRaw: HCkStringBuilder;
email: HCkEmail;

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

http := CkHttp_Create();
CkHttp_putAuthToken(http,'GMAIL-ACCESS-TOKEN');

// The id of the GMail message to download.
id := '166e50fed0b9b0cb';
userId := 'me';

CkHttp_SetUrlVar(http,'userId','me');
CkHttp_SetUrlVar(http,'id',id);

// Fetch the email.
url := 'https://www.googleapis.com/gmail/v1/users/{$userId}/messages/{$id}?format=raw';
sbJson := CkStringBuilder_Create();
success := CkHttp_DownloadSb(http,url,'utf-8',sbJson);
if (success <> True) then
  begin
    Memo1.Lines.Add(CkHttp__lastErrorText(http));
    Exit;
  end;

json := CkJsonObject_Create();
CkJsonObject_LoadSb(json,sbJson);
CkJsonObject_putEmitCompact(json,False);

if (CkHttp_getLastStatus(http) <> 200) then
  begin
    Memo1.Lines.Add(CkJsonObject__emit(json));
    Memo1.Lines.Add('Failed.');
    Exit;
  end;

// The returned JSON contains something like this:

// {
//   "id": "166e50fed0b9b0cb",
//   "threadId": "166e50fed0b9b0cb",
//   "labelIds": [
//     "CATEGORY_SOCIAL",
//     "INBOX"
//   ],
//   "snippet": "...",
//   "historyId": "582477",
//   "internalDate": "1541441317000",
//   "sizeEstimate": 28603,
//   "raw": "BASE64URL_CONTENT"
// }

// The RFC822 MIME of the email is contained in the "raw" as a base64URL encoded string.
// Let's decode and load into a Chilkat email object..
sbRaw := CkStringBuilder_Create();
CkJsonObject_StringOfSb(json,'raw',sbRaw);
CkStringBuilder_Decode(sbRaw,'base64url','utf-8');

email := CkEmail_Create();
CkEmail_SetFromMimeSb(email,sbRaw);

// Now we can use the email API to do whatever we desire..
Memo1.Lines.Add('From: ' + CkEmail__fromAddress(email));
Memo1.Lines.Add('Subject: ' + CkEmail__subject(email));
// ...

CkHttp_Dispose(http);
CkStringBuilder_Dispose(sbJson);
CkJsonObject_Dispose(json);
CkStringBuilder_Dispose(sbRaw);
CkEmail_Dispose(email);

end;