API REFERENCE

Hooks

import type { HookName, HookHandler } from '@rasenganjs/futon';

HookSystem isn't imported directly — every Futon instance owns one at app.hooks. See Hooks for the full lifecycle explanation and examples.

HookSystem

class HookSystem {
  on(name: HookName, handler: HookHandler): void;
  off(name: HookName, handler: HookHandler): void;
  has(name: HookName): boolean;
  emit(name: HookName, ...args: unknown[]): Promise<void>;
  clear(): void;
}
MethodDescription
on(name, handler)Register a handler. Handlers run in registration order and may be async.
off(name, handler)Remove a previously registered handler.
has(name)Whether any handler is registered for name — used internally to skip emit()'s overhead when unused.
emit(name, ...args)Fire all handlers for name, awaiting every async one. If a handler throws, the error is swallowed and the remaining handlers still run.
clear()Remove every registered handler across all hook names — mainly useful for test teardown.
Registering and removing a hook
const onRequest = (ctx) => console.log(ctx.request.method, ctx.request.url);
 
app.hooks.on('beforeRequest', onRequest);
app.hooks.off('beforeRequest', onRequest);

HookName

type HookName = 'beforeRequest' | 'afterResponse' | 'onError';
HookFiresHandler receives
'beforeRequest'Once per request, before the middleware chain runs.(ctx)
'afterResponse'After the Response is produced — both success and error paths.(ctx, response)
'onError'When an unhandled error escapes the middleware chain.(error, ctx)

HookHandler

type HookHandler = (...args: unknown[]) => void | Promise<void>;

The generic handler shape — its effective arguments depend on which HookName it's registered under (see the table above).

Adapters
Errors