@objectstack/observability

Vendor-neutral observability primitives for the ObjectStack framework.

import {
  type MetricsRegistry,
  type Logger,
  NoopMetricsRegistry,
  ConsoleMetricsRegistry,
  OtlpHttpMetricsRegistry,
  JsonLogger,
  SEMCONV,
} from '@objectstack/observability';

What lives here

Three contracts plus matching exporters:

| Contract | Implementations | | ------------------ | -------------------------------------------------------------------------- | | MetricsRegistry | Noop, InMemory, Console, OtlpHttp | | ErrorReporter | Noop, InMemory, Console | | Logger | Noop, Console, Json |

Plus SEMCONV — canonical Prometheus-style metric names emitted by the framework runtime and services.

Wiring

// Self-hosted (any K8s with an OpenTelemetry Collector):
const metrics = new OtlpHttpMetricsRegistry({
  endpoint: 'http://otel-collector:4318',
  resource: { 'service.name': 'objectos', 'deployment.environment': 'prod' },
});

// Cloudflare Workers (handled in apps/cloud — see that repo's exporter):
//   const metrics = new AnalyticsEngineRegistry(env.AE);

// Local dev:
const metrics = new ConsoleMetricsRegistry();

// Tests:
const metrics = new InMemoryMetricsRegistry();
expect(metrics.totalCounter('http_requests_total', { status: '500' })).toBe(0);

The runtime, service-storage, service-cache, and service-package accept a MetricsRegistry and emit the standard names from SEMCONV. Hosts swap implementations at deployment time without touching business code.

Design rules

1. Never throw. Every metric / log / report call site must survive a broken sink.
2. Low cardinality. Use route (pattern), not the raw URL; use shard, not the tenant id.
3. OTLP buffer is flush-on-demand, not interval-driven. Long-running hosts call flush() on a schedule; Workers call it inside ctx.waitUntil at the end of a request.
4. No vendor SDKs. This package depends only on @objectstack/spec. Vendor-specific exporters (Sentry, Cloudflare AE, Datadog) live in the deployment repos that need them.

See docs/design/observability.md (TBD) for the full architecture and the deployment-side wiring contracts.