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Redact sensitive information from your pino logs.




noir([serializers = {}], paths = [], censor = '[Redacted]') => {Pino Serializer Object}


The paths parameter should be an array of strings, describing the nested location of a key in an object.

The path can be represented in dot notation, a.b.c, and/or bracket notation a[b[c]], a.b[c], a[b].c.

Paths also supports the asterisk wildcard (*) to redact all keys within an object. For instance a.b.* applied to the object {a: b: {c: 'foo', d: 'bar'}} will result in the redaction of properties c and d in that object ({"a": "b": {"c": "[Redacted]", "d": "[Redacted]"}}).


The censor can be of any type, for instance an object like {redacted: true} is allowed, as is null. Explicitly passing undefined as the censor will in most cases cause the property to be stripped from the object. Edge cases occur when an array key is redacted, in which case null will appear in the array (this is ultimately a nuance of JSON.stringify, try JSON.stringify(['a', undefined, 'c']))

serializers (optional)

An object containing a previous serializers object. The output of those serializers will be redacted. In this way it is possible to chain standard serializers with pino-noir.


var noir = require('pino-noir')
var redaction = noir([
  'key', '', '', 'check.*', 'also[*]'
], 'Ssshh!')
var pino = require('pino')({
  serializers: redaction
  key: 'will be redacted',
  path: {
    to: {key: 'sensitive', another: 'thing'},
    leading: {to: {another: {key: 'wow'}}}
  check: {out: 'the', wildards: 'yo!'},
  also: ['works', {with: 'arrays'}]
// {"pid":89590,"hostname":"x","level":30,"time":1475104592035,"key":"Ssshh!","path":{"to":{"key":"Ssshh!","another":"thing"},"leading":{"to":{"another":{"key":"Ssshh!"}}}},"check":{"out":"Ssshh!","wildards":"Ssshh!"},"also":["Ssshh!","Ssshh!"],"v":1}

Pino Web Loggers

Pino-noir is also directly compatible with hapi-pino, express-pino-logger, koa-pino-logger, restify-pino-logger.

In each case, use the same serializers option as with pino.

For instance, with express-pino-logger:

var express = require('express')
var noir = require('pino-noir')
var app = express()
  serializers: noir(['key', '', 'check.*', 'also[*]'], 'Ssshh!')

Another example, with Hapi:

const Hapi = require('hapi')
const noir = require('pino-noir')
const server = new Hapi.Server()
  register: require('hapi-pino'),
  options: {
    serializers: noir(['key', '', 'check.*', 'also[*]'], 'Ssshh!')
}, (err) => { /* etc. */ })


Overhead in benchmarks ranges from 0% to 20% depending on the case.

benchPinoTopLevel*10000: 289.380ms
benchNoirTopLevel*10000: 288.425ms
benchPinoNested*10000: 327.763ms
benchNoirNested*10000: 363.749ms
benchPinoDeepNested*10000: 377.189ms
benchNoirDeepNested*10000: 408.555ms
benchPinoVeryDeepNested*10000: 441.848ms
benchNoirVeryDeepNested*10000: 503.567ms
benchPinoWildcardStructure*10000: 395.972ms
benchNoirWildcards*10000: 476.951ms

In these benchmarks, redacting top level keys adds no overhead to logging, redacting using wildcards in a deep nested structure adds 20% overhead.

Redacting various nested structures adds between 8-13% overhead.

Other benchmark runs showed (roughly speaking) deviation of around ¬Ī3%.