Logging

The logging module provides structured, leveled logging with pluggable transports. Log entries are plain objects — easy to forward to any log aggregation service.

Import

import { createLogger } from '@loewen-digital/fullstack/logging'

Basic usage

import { createLogger } from '@loewen-digital/fullstack/logging'

const logger = createLogger({ driver: 'console', level: 'info' })

logger.info('User logged in', { userId: 42 })
logger.warn('Rate limit approaching', { ip: '1.2.3.4', count: 95 })
logger.error('Payment failed', { orderId: 'ord_123', reason: 'insufficient_funds' })

Log levels

Levels follow the standard severity hierarchy. A configured level only emits that level and above.

Level	Use for
debug	Detailed development diagnostics
info	Normal application events
warn	Recoverable issues worth noting
error	Failures that need attention
fatal	Unrecoverable errors

Child loggers

Create a child logger with pre-set context fields:

const requestLogger = logger.child({ requestId: 'req_abc', userId: 7 })
requestLogger.info('Processing payment') // includes requestId and userId automatically

Driver options

Driver	Description
console	Pretty-prints to stdout. Default for development.
file	Appends newline-delimited JSON to a log file.
http	POSTs log batches to an HTTP endpoint (Logtail, Axiom, etc.).

Config options

Option	Type	Default	Description
driver	'console' | 'file' | 'http'	'console'	Transport driver
level	'debug' | 'info' | 'warn' | 'error' | 'fatal'	'info'	Minimum log level
file.path	string	—	Path to log file (file driver)
http.url	string	—	Endpoint URL (http driver)
http.headers	Record<string, string>	{}	Additional request headers