Pascal (Lazarus/Delphi)

Download a Specific GMail Message into a Chilkat Email Object

See more GMail REST API Examples

Demonstrates how to download a GMail message into a Chilkat Email object. 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.Http,
  Chilkat.StringBuilder,
  Chilkat.Email,
  Chilkat.JsonObject;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  http: THttp;
  id: string;
  userId: string;
  url: string;
  sbJson: TStringBuilder;
  json: TJsonObject;
  sbRaw: TStringBuilder;
  email: TEmail;

begin
  success := False;

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

  http := THttp.Create;
  http.AuthToken := 'GMAIL-ACCESS-TOKEN';

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

  http.SetUrlVar('userId','me');
  http.SetUrlVar('id',id);

  //  Fetch the email.
  url := 'https://www.googleapis.com/gmail/v1/users/{$userId}/messages/{$id}?format=raw';
  sbJson := TStringBuilder.Create;
  success := http.DownloadSb(url,'utf-8',sbJson);
  if (success <> True) then
    begin
      WriteLn(http.LastErrorText);
      Exit;
    end;

  json := TJsonObject.Create;
  json.LoadSb(sbJson);
  json.EmitCompact := False;

  if (http.LastStatus <> 200) then
    begin
      WriteLn(json.Emit());
      WriteLn('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 := TStringBuilder.Create;
  json.StringOfSb('raw',sbRaw);
  sbRaw.Decode('base64url','utf-8');

  email := TEmail.Create;
  email.SetFromMimeSb(sbRaw);

  //  Now we can use the email API to do whatever we desire..
  WriteLn('From: ' + email.FromAddress);
  WriteLn('Subject: ' + email.Subject);
  //  ...


  http.Free;
  sbJson.Free;
  json.Free;
  sbRaw.Free;
  email.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.