@storybook/core-events

What is @storybook/core-events?

@storybook/core-events is a package that provides a set of core events for Storybook, a tool for developing UI components in isolation. These events facilitate communication between different parts of Storybook, such as the manager and the preview, enabling features like story selection, control updates, and more.

What are @storybook/core-events's main functionalities?

Story Selection

This feature allows you to programmatically select a story in Storybook. The code sample demonstrates how to emit a story selection event using the SELECT_STORY event type.

const { SELECT_STORY } = require('@storybook/core-events');

// Example of emitting a story selection event
const channel = addons.getChannel();
channel.emit(SELECT_STORY, { kind: 'Button', story: 'Primary' });

Control Updates

This feature allows you to update the controls (args) of a story. The code sample shows how to emit an event to update the arguments of a specific story using the UPDATE_STORY_ARGS event type.

const { UPDATE_STORY_ARGS } = require('@storybook/core-events');

// Example of emitting a control update event
const channel = addons.getChannel();
channel.emit(UPDATE_STORY_ARGS, { storyId: 'button--primary', updatedArgs: { label: 'Click Me' } });

Story Rendering

This feature allows you to listen for when a story has been rendered. The code sample demonstrates how to listen for the STORY_RENDERED event and log a message when a story is rendered.

const { STORY_RENDERED } = require('@storybook/core-events');

// Example of listening for a story rendered event
const channel = addons.getChannel();
channel.on(STORY_RENDERED, (storyId) => {
  console.log(`Story ${storyId} has been rendered`);
});

Other packages similar to @storybook/core-events

eventemitter3

EventEmitter3 is a high-performance event emitter for Node.js and the browser. It provides a similar event-driven architecture but is more general-purpose compared to @storybook/core-events, which is specifically designed for Storybook.

mitt

Mitt is a tiny functional event emitter. It offers a similar event-driven approach but is lightweight and framework-agnostic, making it suitable for a wide range of applications beyond Storybook.

node-event-emitter

Node Event Emitter is a simple and lightweight event emitter for Node.js. It provides basic event handling capabilities similar to @storybook/core-events but lacks the specialized events tailored for Storybook's ecosystem.