@triggery/mobx

Read MobX observable state from a Triggery condition without engaging MobX dependency tracking on the host component.

Install

pnpm add @triggery/core @triggery/react @triggery/mobx mobx

Usage

import { makeAutoObservable } from 'mobx';
import { createTrigger } from '@triggery/core';
import { useMobxCondition } from '@triggery/mobx';

class SettingsStore {
  sound = true;
  notifications = true;
  constructor() {
    makeAutoObservable(this);
  }
}

const settings = new SettingsStore();

const messageTrigger = createTrigger<{
  events: { 'new-message': { text: string } };
  conditions: { settings: { sound: boolean; notifications: boolean } };
  actions: { showToast: { body: string } };
}>({
  id: 'message-received',
  events: ['new-message'],
  required: ['settings'],
  handler({ event, conditions, actions }) {
    if (!conditions.settings.notifications) return;
    actions.showToast?.({ body: event.payload.text });
  },
});

function SettingsBridge() {
  useMobxCondition(messageTrigger, 'settings', () => ({
    sound: settings.sound,
    notifications: settings.notifications,
  }));
  return null;
}

How it works

The read function runs only when a trigger fires. MobX dependency tracking (autorun, reaction, observer) is not engaged from the hook, so:

• No component re-renders from this hook.
• No subscriber stays alive between fires.

If components also need to render the observable, wrap them in observer (or use useObserver from mobx-react-lite) — the two paths are orthogonal.

API

useMobxCondition<S, K>(
  trigger: Trigger<S>,
  name: K,
  read: () => ConditionMap<S>[K],
): void

read is a plain function. Use .get() on boxes, dot-access on observable.object, etc. — exactly as you'd read MobX state anywhere else.

Documentation

Full documentation, recipes and API reference at https://triggeryjs.github.io/packages/mobx/.

Related packages

• @triggery/core — Required peer.
• @triggery/react — Required peer.
• @triggery/zustand — Alternative adapter for Zustand stores.
• @triggery/redux — Alternative adapter for Redux stores.

See the full package list in the repo README.

License

MIT © Aleksey Skhomenko