Async Context

Import from loggily/context. Node.js/Bun only.

Opt-in because it uses AsyncLocalStorage, which has a small runtime cost and isn't available in browsers.

Quick Start

import { enableContextPropagation } from "loggily/context"
import { createLogger } from "loggily"

enableContextPropagation()

const log = createLogger("myapp")
{
  using span = log.span("request")
  log.info?.("handling") // auto-tagged with trace_id, span_id

  // Child spans from ANY logger auto-parent via AsyncLocalStorage
  const db = createLogger("db")
  using dbSpan = db.span("query") // parentId = span.id
}

Once enabled, spans automatically parent to the current context span (even across different loggers), and log messages include trace_id and span_id.

API

Export	Description
enableContextPropagation()	Turn on AsyncLocalStorage tracking
disableContextPropagation()	Turn it off
isContextPropagationEnabled()	Check status
getCurrentSpan()	Get active { spanId, traceId, parentId } or null
runInSpanContext(ctx, fn)	Run fn in a specific span context