var
  AURL, APOSTData: string;
  APOSTData2: TStringList;
  httpsend: THTTPSend;
  stream:tstringstream;
  result:TStringList;
begin
  AURL := 'https://api.stage.mdlp.crpt.ru/api/v1/documents/send';
  APOSTData2 := TStringList.create;
  APOSTData2.LoadFromFile('C:\doc.txt');
  stream:=TStringStream.Create('');
  APOSTData2.SaveToStream(stream);

  httpsend:=THTTPSend.Create;
  httpsend.MimeType:='application/json';
  httpsend.Headers.Add('Authorization: token 5607d0e8-c76c-4f0a-a6e7-f30f03f26e7b');
  httpsend.Document.LoadFromStream(stream);

  try
    httpsend.HTTPMethod('post', AURL);
    result := TStringList.Create;
    result.LoadFromStream(httpsend.Document);
  finally
    showmessage(inttostr(httpsend.ResultCode));
    result.SaveToFile('C:\mark2.txt');
  end;

  vPerson : TPerson;
  vAuth: TAuth;
begin
  //vPerson := TPerson.NewFrom(123, 'Fabricio', 'fabricio.colombo.mva@gmail.com');
  vAuth:=TAuth.NewAuth('9199fe04-42c3-4e81-83b5-120eb5f129f2', '01db16f2-9a4e-4d9f-b5e8-c68f12566fd5', '6d30ff5df90437f98c443317f0beda9cdf626117', 'SIGNED_CODE');
  RestClient1.Resource('http://api.stage.mdlp.crpt.ru/api/v1/auth')
             .Accept(RestUtils.MediaType_Json)
             .ContentType(RestUtils.MediaType_Json)
//          .Post(vPerson);
             .Post(vAuth);
  ShowMessage(Inttostr(RestClient1.ResponseCode));

  type
 {$METHODINFO ON}
  TPerson = class(TObject)
 {$METHODINFO OFF}
   public
    id: Integer;
    name: String;
    email: String;
    createDate: TDateTime;
    class function NewFrom(Id: Integer; Name, EMail: String): TPerson;
  end;

type
 {$METHODINFO ON}
  TAuth = class(TObject)
   {$METHODINFO OFF}
 public
    client_secret: String;
    client_id: String;
    user_id: String;
    auth_type: String;
  class function NewAuth(client_secret, client_id, user_id, auth_type: String): TAuth;
  end;

implementation

{ TPerson }

class function TPerson.NewFrom(Id: Integer; Name, EMail: String): TPerson;
begin
  Result := TPerson.Create;
  Result.Id := Id;
  Result.Name := Name;
  Result.EMail := EMail;
end;

class function TAuth.NewAuth(client_secret, client_id, user_id, auth_type: String): TAuth;
begin
  Result := TAuth.Create;
  Result.client_secret := client_secret;
  Result.client_id := client_id;
  Result.user_id := user_id;
  Result.auth_type := auth_type;
end;