`health-checker/health-checker.helpers`

Purpose

health-checker.helpers carries the pure helpers that back the HealthChecker class: the Zod schemas that validate constructor + per-check options, the default Clock / TimersLike pair, the aggregate-status function, the raw-result normaliser, and the timeout-enforcing wrapper. They are split out of health-checker.ts to keep the main class file inside the project line-count budget and to make each helper independently unit-testable through HealthChecker's tests.

Features

dependencyCheckSchema + optionsSchema — Zod boundary schemas; throw HealthCheckError(INVALID_OPTIONS) on failure when wired in.
defaultClock — () => Date.now().
defaultTimers — setTimeout / clearTimeout adapter for the TimersLike contract.
aggregateStatus(results, isCritical) — pure function mapping a result list to overall CheckStatus.
normalizeResult(name, raw, elapsed, clock) — pure normaliser preserving raw name / timestamp when present.
executeWithTimeout(thunk, ms, timers) — schedules a HealthCheckError(CHECK_TIMEOUT) rejection through the supplied TimersLike.

Usage: Basic

import { aggregateStatus } from "@suaveplan/health-check/health-checker";

const status = aggregateStatus(results, (name) => criticalNames.has(name));

Usage: Advanced

import { executeWithTimeout } from "@suaveplan/health-check/health-checker";

const result = await executeWithTimeout(
    () => probe(),
    250,
    { setTimer: setTimeout, clearTimer: clearTimeout },
);

API Reference

DEFAULT_TIMEOUT: 5000
defaultClock: Clock
defaultTimers: TimersLike
dependencyCheckSchema: ZodObject
optionsSchema: ZodObject
aggregateStatus(results, isCritical) → CheckStatus
normalizeResult(name, raw, elapsed, clock) → CheckResult
executeWithTimeout<T>(thunk, ms, timers) → Promise<T>

Implementation Notes

executeWithTimeout carries a settled flag to absorb the race between the timer firing and the thunk resolving. Either path is responsible for flipping the flag; the other path no-ops. clearTimer is only called on the resolution / rejection side because the timer-fired side has already executed and there is nothing to cancel. Rejections from the thunk are coerced into HealthCheckError(CHECK_EXECUTION_FAILED) so the outer runCheck always sees a typed error and can route on code instead of instanceof Error. The Zod schemas are constructed at module top level — instantiating them once per import keeps the per-call overhead to a single safeParse invocation.

2.6 KiB Raw Blame History

health-checker/health-checker.helpers