guarded

Wrap a function with global error handling so HTTP-aware exceptions are translated to typed domain exceptions and any other error is funneled through a single onError hook. Don't combine guarded with try/catch at the call site — let the global handler in your app deal with the typed exceptions.

Importing

import { guarded } from '@basmilius/common';

Usage

import { guarded, useService } from '@basmilius/common';
import { OrderService } from '@/services/OrderService';

const {getOrder} = useService(OrderService);

const safeGetOrder = guarded(getOrder);
const loggedGetOrder = guarded(getOrder, err => console.error(err));

guarded understands the request-error and unsanctioned-request markers from @basmilius/http-client and translates them as follows:

Trigger	Throws
isRequestError(err) && err.statusCode === 403	ForbiddenException
isUnsanctionedRequest(err)	UnauthorizedException
Any other error, when onError is provided	HandledException (after invoking onError)
Any other error, without onError	The original error is re-thrown

If a function is already guarded — guarded marks the wrapper with an internal symbol — the helper unwraps the original before re-wrapping so you never get double error-handling on the same call.

Used by

• useService — wraps every service method by default
• onError — partially-applies guarded with a captured onError callback

Type signature

declare function guarded<T extends Function>(fn: T): T;
declare function guarded<T extends Function>(
    fn: T,
    onError: (err: Error) => void
): T;

See also

• onError
• useService
• Errors