Instrument Fastify APIs.

The framework adapter uses @apirelio/core for the common event contract and bounded asynchronous transport.

npm install @apirelio/fastify @apirelio/core

The plugin times requests in onRequest, remembers framework errors in onError and captures the final route and status in onResponse.

import Fastify from 'fastify'
import apirelioFastify from '@apirelio/fastify'

const app = Fastify()
await app.register(apirelioFastify, {
  apiKey: process.env.APIRELIO_API_KEY ?? '',
  service: 'billing-api',
  environment: 'production',
  includeRoutes: ['/api/**'],
  excludeRoutes: ['/api/health', '/api/internal/**'],
  resolveCustomer: request => request.user ? {
    id: String(request.user.companyId),
    plan: request.user.companyPlan,
  } : null,
})

Use stable external IDs from your authentication model. Customer names and plans can evolve without breaking analytics history.

resolveApplication: request => ({
  id: String(request.headers['x-application-id']),
}),
resolveErrorCode: (_request, _reply, error) =>
  error && 'code' in error ? String(error.code) : null

Fastify onClose automatically flushes the bounded queue when the server closes.

includeRoutes accepts exact paths or prefixes ending in /**. Explicit excludeRoutes always take precedence, keeping health checks, internal endpoints and presentation routes out of API analytics.

Request and response bodies, authorization values, cookies, query values, email addresses and client IP addresses are not captured. Custom scalar metadata must be explicitly allow-listed.