Logging to STDOUT and a file with node/pino

Question

I am sharing this as I struggled to get a pino logger to write to both STDOUT and a log file:

const dest = new stream.PassThrough();
dest.pipe(process.stdout);
dest.pipe(fs.createWriteStream('/logs/file.log', { flags: 'a' }));
const logger = pino({ level: 'info' }, dest);

As this appears very low level, I wonder if this is the right way to do this.

score 11 · Accepted Answer · edited Oct 11 '22 at 12:10

11

A bit late but pino-multi-stream may be what you want. I followed this section here and it works for me in TypeScript for my purpose. You could try something like this:

const fs = require('fs');
const pinoms = require('pino-multi-stream')

const streams = [
  { stream: process.stdout },
  { stream: fs.createWriteStream('/logs/file.log', { flags: 'a' }) },
]

const logger = pino({ level: 'info' }, pinoms.multistream(streams));

edited Oct 11 '22 at 12:10

Lee Goddard

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answered Apr 06 '21 at 16:01

wtwtwt

368
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7

From 10th June 2022, `pino-multi-stream` is now deprecated (https://www.npmjs.com/package/pino-multi-stream) and the repo has been archived (https://github.com/pinojs/pino-multi-stream). Pino 7/8 support multiple streams so it is recommended to use the native support instead – Woodz Nov 22 '22 at 05:11
There is also a performace hit using pino-multi-stream, don't use it if performance is important. – Brian Jul 01 '23 at 02:28

score 7 · Answer 2 · answered Mar 22 '23 at 17:42

if you are using pino 7+ you can just use the following:

const transport = pino.transport({
  targets: [
    {
      level: 'trace',
      target: 'pino/file',
      options: {
        destination: logPath,
      },
    },
    {
      level: 'trace',
      target: 'pino-pretty',
      options: {},
    },
  ],
});

export const log = pino(options, transport);

Logging to STDOUT and a file with node/pino

2 Answers2

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