winston-daily-rotate-file

What is winston-daily-rotate-file?

The winston-daily-rotate-file npm package is a transport plugin for the winston logger that outputs log messages to a file, rotating the file automatically based on time, size, or both. It is commonly used to manage log files, ensuring they are kept to a manageable size and are rotated out over time for archival purposes.

What are winston-daily-rotate-file's main functionalities?

Time-based log rotation

This feature allows logs to be rotated daily. The '%DATE%' pattern in the filename is replaced with the current date in the 'YYYY-MM-DD' format. Logs older than 14 days are deleted, and logs are zipped when they are rotated.

const winston = require('winston');
const DailyRotateFile = require('winston-daily-rotate-file');

const logger = winston.createLogger({
  transports: [
    new DailyRotateFile({
      filename: 'application-%DATE%.log',
      datePattern: 'YYYY-MM-DD',
      zippedArchive: true,
      maxSize: '20m',
      maxFiles: '14d'
    })
  ]
});

Size-based log rotation

This feature allows logs to be rotated when they reach a certain size. In this example, the log file is rotated when it reaches 20 megabytes. The 'maxFiles' option is set to 5, which means that a maximum of 5 rotated log files will be kept.

const winston = require('winston');
const DailyRotateFile = require('winston-daily-rotate-file');

const logger = winston.createLogger({
  transports: [
    new DailyRotateFile({
      filename: 'application-%DATE%.log',
      datePattern: 'YYYY-MM-DD',
      zippedArchive: true,
      maxSize: '20m',
      maxFiles: '5'
    })
  ]
});

Customizable file compression

This feature allows the rotated log files to be compressed using gzip. The 'zippedArchive' option is set to true, enabling this functionality.

const winston = require('winston');
const DailyRotateFile = require('winston-daily-rotate-file');

const logger = winston.createLogger({
  transports: [
    new DailyRotateFile({
      filename: 'application-%DATE%.log',
      datePattern: 'YYYY-MM-DD',
      zippedArchive: true
    })
  ]
});

Other packages similar to winston-daily-rotate-file

rotating-file-stream

This package provides a stream that writes logs to a file and rotates it based on time or size, similar to winston-daily-rotate-file. It is not tied to any specific logging library and can be used with any Node.js stream-compatible logging tool.

file-stream-rotator

Similar to winston-daily-rotate-file, this package is used to rotate logs on a time basis. It does not depend on winston and can be used independently to manage log file rotation in any Node.js application.

bunyan-rotating-file-stream

This package is a rotating file stream for the Bunyan logging library. It offers functionality similar to winston-daily-rotate-file but is specifically designed to work with Bunyan instead of winston.

README

winston-daily-rotate-file

A transport for winston which logs to a rotating file each day.

Usage

  var winston = require('winston');
  require('winston-daily-rotate-file');

  var transport = new (winston.transports.DailyRotateFile)({
    filename: './log',
    datePattern: 'yyyy-MM-dd.',
    prepend: true,
    level: process.env.ENV === 'development' ? 'debug' : 'info'
  });

  var logger = new (winston.Logger)({
    transports: [
      transport
    ]
  });

  logger.info('Hello World!');

The DailyRotateFile transport can rotate files by minute, hour, day, month, year or weekday. In addition to the options accepted by the File transport, the Daily Rotate File Transport also accepts the following options:

• datePattern: A string representing the pattern to be used when appending the date to the filename (default 'yyyy-MM-dd'). The meta characters used in this string will dictate the frequency of the file rotation. For example, if your datePattern is simply 'HH' you will end up with 24 log files that are picked up and appended to every day.
• prepend: Defines if the rolling time of the log file should be prepended at the beginning of the filename (default 'false').
• localTime: A boolean to define whether time stamps should be local (default 'false' means that UTC time will be used).
• zippedArchive: A boolean to define whether or not to gzip archived log files (default 'false').
• maxDays: A number representing the maximum number of days a log file will be saved. Any log file older than this specified number of days will be removed. If not value or a 0, no log files will be removed.
• createTree: When combined with a datePattern that includes path delimiters, the transport will create the entire folder tree to the log file. Example: datePattern: '/yyyy/MM/dd.log', createTree: true will create the entire path to the log file prior to writing an entry.

Valid meta characters in the datePattern are:

• yy: Last two digits of the year.
• yyyy: Full year.
• M: The month.
• MM: The zero padded month.
• d: The day.
• dd: The zero padded day.
• H: The hour.
• HH: The zero padded hour.
• m: The minute.
• mm: The zero padded minute.
• ddd: The weekday (Mon, Tue, ..., Sun).

Metadata: Logged via util.inspect(meta);

LICENSE

MIT

AUTHOR: Charlie Robbins

MAINTAINER: Matt Berther