Method HandleGET_mxnWindow

Modules/RESTAPI/src/mitkRenderingController.cpp:1676–1770

}

void RenderingController::HandleGET_mxnWindow(const httplib::Request& req, httplib::Response& res) const
{
  const auto id = ReadRequiredPathParam(req, "id");

  // Shape-only check: malformed ids never reach the bridge dispatch.
  if (!IsValidMxNWindowId(id))
  {
    const auto error = ErrorResponse::InvalidRequest(
      "Malformed MxN window id '" + id + "'. Expected pattern: <prefix>__<bare> with URL-segment-safe characters.",
      req.path);
    this->SendErrorResponse(res, 400, error);
    return;
  }

  if (m_RenderWindowBridge == nullptr || !m_RenderWindowBridge->HasMxNWindowListProvider())
  {
    const auto error = ErrorResponse::RenderWindowNotAvailable(req.path);
    this->SendErrorResponse(res, 503, error);
    return;
  }

  std::vector<MxNWindowInfo> windows;
  try
  {
    windows = m_RenderWindowBridge->ListMxNWindows();
  }
  catch (const mitk::Exception& e)
  {
    // mitk::Exception from the bridge layer signals a binding-contract
    // violation surfaced via mitkThrow (e.g. an unparseable v2
    // view_direction). Map to 422 RENDERING_ERROR -- the request shape was
    // valid; the rendering backend reports an unrecoverable state. The
    // generic MapBridgeException below would otherwise emit 500
    // INTERNAL_ERROR, which is the wrong status class for a downstream
    // contract failure.
    const auto error = ErrorResponse::RenderingError(e.what(), req.path);
    this->SendErrorResponse(res, 422, error);
    return;
  }
  catch (const std::exception& e)
  {
    const auto [status, payload] = MapBridgeException(e, req.path);
    this->SendErrorResponse(res, status, payload);
    return;
  }

  // TODO(v3): replace the O(n) scan with a per-window descriptor query once
  // the bridge surface exposes a GetMxNWindowDescriptor(id) callback.
  // Tracked alongside the v3 migration checklist in
  // QmitkRestApiBridgeBindings.cpp; acceptable at v1.2 scale (dozens of
  // cells at most).
  const auto it = std::find_if(windows.begin(), windows.end(),
    [&](const MxNWindowInfo& w) { return w.id == id; });
  if (it == windows.end())
  {
    const auto error = ErrorResponse::RenderWindowNotFound(id, req.path);
    this->SendErrorResponse(res, 404, error);
    return;