pino-http  

High-speed HTTP logger for Node.js

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

* Installation
* Usage
* Benchmarks
* API
* Team
* Acknowledgements
* License

Benchmarks

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

* http-ndjson (equivalent info): 7730.73 req/sec
* http-ndjson (standard minimum info): 9522.37 req/sec
* pino-http: 21496 req/sec
* pino-http (extreme): 25770.91 req/sec
* no logger: 46139.64 req/sec

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

Install

``
npm i pino-http --save
`

Example

`js
'use strict'

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

var 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
[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

$3

opts: it has all the options as pino and

* logger: pino-http can reuse a pino instance if passed with the logger property
* genReqId: you can pass a function which gets used to generate a request id. The first argument is the request itself. As fallback pino-http is just using an integer. This default might not be the desired behavior if you're running multiple instances of the app
* useLevel: the logger level pino-http is using to log out the response. default: info
customLogLevel: set to a function (res, err) => { / returns level name string */ }. This function will be invoked to determine the level at which the log should be issued. This option is mutually exclusive with the useLevel option. The first argument is the HTTP response. The second argument is an error object if an error has occurred in the request.

* stream: same as the second parameter

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

#### Examples

##### Logger options

`js
'use strict'

var http = require('http')
var server = http.createServer(handle)
var pino = require('pino')
var logger = require('pino-http')({
// Reuse an existing logger instance
logger: pino(),

// Define a custom request id function
genReqId: function (req) { return req.id },

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

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


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

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

server.listen(3000)
`

##### 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:

`js
var http = require('http')
var logger = require('pino-http')()
var someImportantThingThatHasToBeFirst = require('some-important-thing')
http.createServer((req, res) => {
res[logger.startTime] = Date.now()
someImportantThingThatHasToBeFirst(req, res)
logger(req, res)
res.end('hello world')
}).listen(3000)
`

#### 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:

`js
{
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:

`js
{
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:

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

Team

$3

$3

Acknowledgements

This project was kindly sponsored by nearForm.

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

License

MIT