Openfuse SDK for Node.js

Node.js client for the Openfuse circuit breaker service. Zero runtime dependencies.

Installation

npm install @openfuseio/sdk

Requirements

• Node.js >= 22.0.0
• Openfuse account with an SDK client configured

Usage

import { OpenfuseCloud } from '@openfuseio/sdk'

const client = new OpenfuseCloud({
  systemSlug: 'checkout',
  clientId: 'your-client-id',
  clientSecret: 'your-client-secret',
})

await client.bootstrap()

const recommendations = await client.withBreaker('recommendations', () => fetchRecommendations(userId),
  { onOpen: () => [] },
)

If recommendations breaker is open, onOpen returns an empty array immediately, no network call attempted.

Circuit Breaker States

• Closed — Requests flow through normally
• Open — Requests blocked, fallback triggered
• Half-Open — Probe requests allowed to test recovery

API Reference

Core Methods

| Method | Description | | ----------------------------- | ----------------------------------------------------- | | bootstrap() | Fetch breaker configuration. Call once at startup. | | withBreaker(slug, fn, opts) | Execute function with circuit breaker protection. | | shutdown() | Flush metrics and clean up. Call before process exit. |

State Methods

| Method | Description | | ------------------------- | ------------------------------------- | | isOpen(slug, signal?) | Returns true if breaker is open. | | isClosed(slug, signal?) | Returns true if breaker is closed. | | getBreaker(slug) | Returns breaker details. | | listBreakers() | Returns all breakers for the system. | | invalidate() | Clear cached state and flush metrics. |

withBreaker Options

await client.withBreaker('my-breaker', () => doSomething(), {
  onOpen: () => fallbackValue, // Called when breaker is open
  onUnknown: () => degradedValue, // Called when state can't be determined
  timeout: 5000, // Timeout in ms for the wrapped function
  signal: abortController.signal, // AbortSignal for cancellation
})

Self-Hosted

import { Openfuse } from '@openfuseio/sdk'

const client = new Openfuse({
  baseUrl: 'https://openfuse.internal.mycompany.com',
  systemSlug: 'checkout',
  clientId: 'your-client-id',
  clientSecret: 'your-client-secret',
})

await client.bootstrap()

License

Elastic License 2.0