EvFlow is a simple event management library that supports dependency management, lifecycle hooks, middleware, and event publishing/subscription. It's designed for use cases involving general business flow control.
npm install evflowEvFlow provides a legacy build for compatibility with older browsers.
If your project needs to support older versions of browsers, please import it as follows:
import {Dispatcher} from 'evflow/legacy';import {Dispatcher} from 'evflow';
const hub = new Dispatcher();
// Register dependencies
hub.add('payment_processed');
hub.add('inventory_check');
// Register main event (dependencies already exist)
hub.add('order_created', ['payment_processed', 'inventory_check']);
// Register handlers for all dependencies
hub.handle('payment_processed', async () => {
console.log('Processing payment...');
return {success: true};
});
hub.handle('inventory_check', async () => {
console.log('Checking inventory...');
return {stock: 100};
});
hub.handle('order_created', async (_, paymentResult, inventoryResult) => {
console.log('Order created!', paymentResult, inventoryResult);
});
// Dispatch event
await hub.run('order_created');
// Console logs
/*
Processing payment...
Checking inventory...
Order created! { success: true } { stock: 100 }
*/| Method | Description |
|---|---|
add(event, deps?, tags?) |
Registers an event. |
handle(eventId, handler) |
Registers an event handler. |
run(eventId, options?) |
Dispatches a single event. |
runAll(eventIds?, mode?, options?) |
Dispatches multiple events. |
use(middleware) |
Adds middleware to the event flow. |
subscribe(eventId, callback) |
Subscribes to state changes for a given event. |
unsubscribe(eventId, callback) |
Unsubscribes from an event's state changes. |
onLifecycle(phase, hook) |
Registers a global lifecycle hook. |
onEvent(eventId, phase, hook) |
Registers a lifecycle hook for a specific event. |
clear() |
Clears all registered events, handlers, and state. |
Contributions are welcome! Feel free to submit issues or pull requests.