WinCCOA WebComponent Dashboard — wui-oarxjs-data

This package is part of the workspace for the WinCC Open Architecture WebComponent Dashboard, built using Lit and managed with Nx.

Usage information and reference details can be found in the WinCC OA documentation.

Overview

Cached, reference-counted wrappers around the bare-metal OaRxJsApi (from @etm-professional-control/oa-rx-js-api). Pick the handlers in this package when the same data is consumed by more than one component or service — they share a single underlying server subscription per DP and emit cached values immediately on subscribe.

Use the underlying OaRxJsApi directly for one-off subscriptions or when you need its full feature surface; use the handlers here when you want subscription sharing, ref-counting, and immediate cached values. See @etm-professional-control/oa-rx-js-api README for the underlying API.

Services

Resolved via tsyringe. Subscribe to one or more datapoints in a single call. Multiple subscribers to the same DP share one underlying connection.

import { DpConnectHandler } from '@wincc-oa/wui-oarxjs-data/dp-connect-handler.js';
import { container } from 'tsyringe';

const dpConnectHandler = container.resolve<DpConnectHandler>(DpConnectHandler);

dpConnectHandler.dpConnect(['System1:Dp1.', 'System1:Dp2.']).subscribe((values) => {
  // emission shape: { 'System1:Dp1.': v1, 'System1:Dp2.': v2 } — keyed by dpName
  const v1 = values['System1:Dp1.'] as number;
  const v2 = values['System1:Dp2.'] as number;
});

Options:

dpConnectHandler.dpConnect(dataPaths, {
  throwErrorOnMissingDataPaths: true, // surface missing-DP errors instead of returning silent empties
  throttle: true // sample updates to ~1/s via a central timer (default: false)
});

| Aspect | OaRxJsApi.dpConnect | DpConnectHandler.dpConnect | | -------------- | --------------------------------------------------------- | ----------------------------------------------------------------------- | | Signature | dpName: string \| string[] | dataPaths: string[] (array only) | | Emission shape | { dp: string[], value: unknown[] } (positional) | { [dpName: string]: unknown } (keyed by name) | | Initial value | First emission when backend responds (use true 2nd arg) | From cache, immediately on subscribe | | Sharing | One server connection per call | Reference-counted; subscribers share one underlying connection | | Throttling | None | Optional throttle option | | When to pick | One-off subscription, single owner | DP shared across components/services, or you want cached initial values |

Used by

• wui-context-dpconnect (and other wui-context-* elements that read DPs) — see @wincc-oa/wui-oarxjs-context README
• Long-lived shared services in the dashboard resolve DpConnectHandler rather than calling OaRxJsApi.dpConnect directly

License

MIT