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Type Alias: EventMiddleware()<T>

EventMiddleware<T> = (event: string, data: T, next: () => Promise<void> | void) => Promise<void> | void

Defined in: electron/events/TypedEventBus.ts:128

Middleware function for event processing.

Type Parameters​

T​

T = unknown

The type of event data payload.

Parameters​

event​

string

Name of the event being processed.

data​

T

Event data payload (read-only for inspection).

next​

() => Promise<void> | void

Function to call to continue to the next middleware.

Returns​

Promise<void> | void

A promise that resolves when the middleware chain is complete.

Remarks​

Middleware can inspect event data, add logging, collect metrics, perform validation, or handle other cross-cutting concerns. Middleware should NOT modify the data object, as modifications will not be reflected in the final event delivered to listeners. Call next() to continue processing or throw an error to stop the middleware chain. Data transformations should be performed before calling TypedEventBus.emitTyped.

Example​

const loggingMiddleware: EventMiddleware = async (event, data, next) => {
    console.log(`Processing event: ${event}`);
    await next(); // Continue to next middleware
    console.log(`Completed event: ${event}`);
};

Throws​

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global\_Objects/Error if the middleware wishes to abort event processing.