Pino v7 logger transport transformer to console.log colorized terminal output, for use within a pino transport pipeline

pino.colorisedTerminalTransformTransport.mjs

import { Writable } from 'stream'

export default (options) => {
	const levels = {
		// https://github.com/pinojs/pino/blob/master/docs/api.md#logger-level
		10: `\x1b[2m[>]\x1b[0m`, //trace
		20: `\x1b[35m[DEBUG]\x1b[0m`, //debug
		30: `\x1b[36m[>]`, //info
		40: `\x1b[33m[?]`, //warn
		50: `\x1b[31m[!]`, //error
		60: `\x1b[41m[!!!]`, //fatal
		Infinity: ``,
	}

	const colorizedLoggerTransportStream = new Writable({
		write(chunk, enc, cb) {
			const logEvents = chunk.toString().match(/[^\r\n]+/g) // split into lines
			logEvents.forEach((logEvent) => {
				const { level, time, msg } = JSON.parse(logEvent)
				const timestamp = new Date(time).toISOString().slice(11).substring(8, 0)
				console.log(`\x1b[2m${timestamp}\x1b[0m ${levels[level] || ''} ${msg}\x1b[0m`)
			})
			cb()
		},
	})
	return colorizedLoggerTransportStream
}