Home

Awesome

pino-http  Build Status

High-speed HTTP logger for Node.js

To our knowledge, pino-http is the fastest HTTP logger in town.

Benchmarks

Benchmarks log each request/response pair while returning 'hello world', using autocannon with 100 connections and 10 pipelined requests.

All benchmarks where taken on a Macbook Pro 2013 (2.6GHZ i7, 16GB of RAM).

Install

npm i pino-http --save

Example

'use strict'

const http = require('http')
const server = http.createServer(handle)

const logger = require('pino-http')()

function handle (req, res) {
  logger(req, res)
  req.log.info('something else')
  res.end('hello world')
}

server.listen(3000)

$ node example.js | pino-pretty
[2016-03-31T16:53:21.079Z] INFO (46316 on MBP-di-Matteo): something else
    req: {
      "id": 1,
      "method": "GET",
      "url": "/",
      "headers": {
        "host": "localhost:3000",
        "user-agent": "curl/7.43.0",
        "accept": "*/*"
      },
      "remoteAddress": "::1",
      "remotePort": 64386
    }
[2016-03-31T16:53:21.087Z] INFO (46316 on MBP-di-Matteo): request completed
    res: {
      "statusCode": 200,
      "header": "HTTP/1.1 200 OK\r\nX-Powered-By: restify\r\nContent-Type: text/html; charset=utf-8\r\nContent-Length: 11\r\nETag: W/\"b-XrY7u+Ae7tCTyyK7j1rNww\"\r\nDate: Thu, 31 Mar 2016 16:53:21 GMT\r\nConnection: keep-alive\r\n\r\n"
    }
    responseTime: 10
    req: {
      "id": 1,
      "method": "GET",
      "url": "/",
      "headers": {
        "host": "localhost:3000",
        "user-agent": "curl/7.43.0",
        "accept": "*/*"
      },
      "remoteAddress": "::1",
      "remotePort": 64386
    }

API

pinoHttp([opts], [stream])

opts: it has all the options as pino and

stream: the destination stream. Could be passed in as an option too.

Examples

Use as Express middleware
const express = require('express')
const logger = require('pino-http')

const app = express()

app.use(logger())

function handle (req, res) {
  req.log.info('something else')
  res.end('hello world')
}

app.listen(3000)
Logger options
'use strict'

const http = require('http')
const server = http.createServer(handle)
const { randomUUID } = require('node:crypto')
const pino = require('pino')
const logger = require('pino-http')({
  // Reuse an existing logger instance
  logger: pino(),

  // Define a custom request id function
  genReqId: function (req, res) {
    const existingID = req.id ?? req.headers["x-request-id"]
    if (existingID) return existingID
    const id = randomUUID()
    res.setHeader('X-Request-Id', id)
    return id
  },

  // Define custom serializers
  serializers: {
    err: pino.stdSerializers.err,
    req: pino.stdSerializers.req,
    res: pino.stdSerializers.res
  },

  // Set to `false` to prevent standard serializers from being wrapped.
  wrapSerializers: true,

  // Logger level is `info` by default
  useLevel: 'info',

  // Define a custom logger level
  customLogLevel: function (req, res, err) {
    if (res.statusCode >= 400 && res.statusCode < 500) {
      return 'warn'
    } else if (res.statusCode >= 500 || err) {
      return 'error'
    } else if (res.statusCode >= 300 && res.statusCode < 400) {
      return 'silent'
    }
    return 'info'
  },

  // Define a custom success message
  customSuccessMessage: function (req, res) {
    if (res.statusCode === 404) {
      return 'resource not found'
    }
    return `${req.method} completed`
  },

  // Define a custom receive message
  customReceivedMessage: function (req, res) {
    return 'request received: ' + req.method
  },

  // Define a custom error message
  customErrorMessage: function (req, res, err) {
    return 'request errored with status code: ' + res.statusCode
  },

  // Override attribute keys for the log object
  customAttributeKeys: {
    req: 'request',
    res: 'response',
    err: 'error',
    responseTime: 'timeTaken'
  },

  // Define additional custom request properties
  customProps: function (req, res) {
    return {
      customProp: req.customProp,
      // user request-scoped data is in res.locals for express applications
      customProp2: res.locals.myCustomData
    }
  }
})

function handle (req, res) {
  logger(req, res)
  req.log.info('something else')
  res.log.info('just in case you need access to logging when only the response is in scope')
  res.end('hello world')
}

server.listen(3000)
Structured Object Hooks

It is possible to override the default structured object with your own. The hook is provided with the pino-http base object so that you can merge in your own keys.

This is useful in scenarios where you want to augment core pino-http logger object with your own event labels.

If you simply want to change the message which is logged then check out the custom[Received|Error|Success]Message hooks e.g. customReceivedMessage

const logger = require('pino-http')({
  //... remaining config omitted for brevity
  customReceivedObject: (req, res, val) => {
    return {
      category: 'ApplicationEvent',
      eventCode: 'REQUEST_RECEIVED'
    };
  },

  customSuccessObject: (req, res, val) => {
    return {
      ...val,
      category: 'ApplicationEvent',
      eventCode:
        res.statusCode < 300
          ? 'REQUEST_PROCESSED'
          : 'REQUEST_FAILED'
    };
  },

  customErrorObject: (req, res, error, val) => {
    const store = storage.getStore();
    const formattedBaggage = convertBaggageToObject(store?.baggage);

    return {
      ...val,
      category: 'ApplicationEvent',
      eventCode: 'REQUEST_FAILED'
    };
  }

  // ...remaining config omitted for brevity
})
PinoHttp.logger (P.Logger)

The pinoHttp instance has a property logger, which references to an actual logger instance, used by pinoHttp. This instance will be a child of an instance, passed as opts.logger, or a fresh one, if no opts.logger is passed. It can be used, for example, for doing most of the things, possible to do with any pino instance, for example changing logging level in runtime, like so:

const pinoHttp = require('pinoHttp')();
pinoHttp.logger.level = 'silent';
pinoHttp.startTime (Symbol)

The pinoHttp function has a property called startTime which contains a symbol that is used to attach and reference a start time on the HTTP res object. If the function returned from pinoHttp is not the first function to be called in an HTTP servers request listener function then the responseTime key in the log output will be offset by any processing that happens before a response is logged. This can be corrected by manually attaching the start time to the res object with the pinoHttp.startTime symbol, like so:

const http = require('http')
const logger = require('pino-http')()
const someImportantThingThatHasToBeFirst = require('some-important-thing')
http.createServer((req, res) => {
  res[logger.startTime] = Date.now()
  someImportantThingThatHasToBeFirst(req, res)
  logger(req, res)
  res.log.info('log is available on both req and res');
  res.end('hello world')
}).listen(3000)
Custom formatters

You can customize the format of the log output by passing a Pino transport.

const logger = require('pino-http')({
  quietReqLogger: true, // turn off the default logging output
  transport: {
    target: 'pino-http-print', // use the pino-http-print transport and its formatting output
    options: {
      destination: 1,
      all: true,
      translateTime: true
    }
  }
})

Default serializers

pinoHttp.stdSerializers.req

Generates a JSONifiable object from the HTTP request object passed to the createServer callback of Node's HTTP server.

It returns an object in the form:

{
  pid: 93535,
  hostname: 'your host',
  level: 30,
  msg: 'my request',
  time: '2016-03-07T12:21:48.766Z',
  v: 0,
  req: {
    id: 42,
    method: 'GET',
    url: '/',
    headers: {
      host: 'localhost:50201',
      connection: 'close'
    },
    remoteAddress: '::ffff:127.0.0.1',
    remotePort: 50202
  }
}
pinoHttp.stdSerializers.res

Generates a JSONifiable object from the HTTP response object passed to the createServer callback of Node's HTTP server.

It returns an object in the form:

{
  pid: 93581,
  hostname: 'myhost',
  level: 30,
  msg: 'my response',
  time: '2016-03-07T12:23:18.041Z',
  v: 0,
  res: {
    statusCode: 200,
    header: 'HTTP/1.1 200 OK\r\nDate: Mon, 07 Mar 2016 12:23:18 GMT\r\nConnection: close\r\nContent-Length: 5\r\n\r\n'
  }
}

Custom serializers

Each of the standard serializers can be extended by supplying a corresponding custom serializer. For example, let's assume the request object has custom properties attached to it, and that all of the custom properties are prefixed by foo. In order to show these properties, along with the standard serialized properties, in the resulting logs, we can supply a serializer like:

const logger = require('pino-http')({
  serializers: {
    req (req) {
      Object.keys(req.raw).forEach((k) => {
        if (k.startsWith('foo')) {
          req[k] = req.raw[k]
        }
      })
      return req
    }
  }
})

If you prefer to work with the raw value directly, or you want to honor the custom serializers already defined by opts.logger, you can pass in opts.wrapSerializers as false:

const logger = require('pino-http')({
  wrapSerializers: false,
  serializers: {
    req (req) {
      // `req` is the raw `IncomingMessage` object, not the already serialized request from `pino.stdSerializers.req`.
      return {
        message: req.foo
      };
    }
  }
})
Logging request body

Logging of requests' bodies is disabled by default since it can cause security risks such as having private user information (password, other GDPR-protected data, etc.) logged (and persisted in most setups). However if enabled, sensitive information can be redacted as per redaction documentation.

Furthermore, logging more bytes does slow down throughput. This video by pino maintainers Matteo Collina & David Mark Clements goes into this in more detail.

After considering these factors, logging of the request body can be achieved as follows:

const http = require('http')
const logger = require('pino-http')({
  serializers: {
    req(req) {
      req.body = req.raw.body;
      return req;
    },
  },
});
Custom serializers + custom log attribute keys

If custom attribute keys for req, res, or err log keys have been provided, serializers will be applied with the following order of precedence:

serializer matching custom key > serializer matching default key > default pino serializer

Team

Matteo Collina

https://github.com/mcollina

https://www.npmjs.com/~matteo.collina

https://twitter.com/matteocollina

David Mark Clements

https://github.com/davidmarkclements

https://www.npmjs.com/~davidmarkclements

https://twitter.com/davidmarkclem

<a name="acknowledgements"></a>

Acknowledgements

This project was kindly sponsored by nearForm.

Logo and identity designed by Beibhinn Murphy O'Brien: https://www.behance.net/BeibhinnMurphyOBrien.

License

MIT