Enforcing the use of actions

It should come as no surprise that MobX strongly recommends using actions for modifying observables. In fact, this can be made mandatory by configuring MobX to always enforce this policy, also called the strict mode. The configure() function can be used to set the enforceActions option to true. MobX will now throw an error if you try to modify an observable outside of an action.

Going back to our previous example with cart, if we try to modify it outside an action, MobX will fail with an error, as you can see from the following example:

import { observable, configure } from 'mobx';

configure({
    enforceActions: true,
});

// Modifying outside of an action
cart.items.push({ name: 'test', quantity: 1 });
cart.modified = new Date();

Error: [mobx] Since strict-mode is enabled, changing observed observable values outside actions is not allowed. Please wrap the code in an `action` if this change is intended. Tried to modify: ObservableObject@1.items