file-stream-rotator
NodeJS file stream rotator
Purpose
To provide an automated rotation of Express/Connect logs based on date.
Install
npm install file-stream-rotator
Usage
// Default date added at the end of the file
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test.log", frequency:"daily", verbose: false});
// Default date added using file pattern
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test-%DATE%.log", frequency:"daily", verbose: false});
// Custom date added using file pattern using moment.js formats
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test-%DATE%.log", frequency:"daily", verbose: false, date_format: "YYYY-MM-DD"});
// Rotate when the date format as calculated by momentjs is different (e.g monthly)
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test-%DATE%.log", frequency:"custom", verbose: false, date_format: "YYYY-MM"});
// Rotate when the date format as calculated by momentjs is different (e.g weekly)
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test-%DATE%.log", frequency:"custom", verbose: false, date_format: "YYYY-ww"});
// Rotate when the date format as calculated by momentjs is different (e.g AM/PM)
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test-%DATE%.log", frequency:"custom", verbose: false, date_format: "YYYY-MM-DD-A"});
// Rotate on given minutes using the 'm' option i.e. 5m or 30m
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test.log", frequency:"5m", verbose: false});
// Rotate on the hour or any specified number of hours
var rotatingLogStream = require('file-stream-rotator').getStream({filename:"/tmp/test.log", frequency:"1h", verbose: false});
//.....
// Use new stream in express
app.use(express.logger({stream: rotatingLogStream, format: "default"}));
//.....
You can listen to the open, close, error and finish events generated by the open stream. You can also listen for custom events:
rotate: that will pass two parameters to the callback: oldFilename and newFilename new: that will pass two parameters to the callback: oldFilename and newFilename
You can also limit the size of each file by adding the size option using "k", "m" and "g" to specify the size of the file in kiloybytes, megabytes or gigabytes. When it rotates a file based on size, it will add a number to the end and increment it for every time the file rotates in the given period as shown below.
3078 7 Mar 13:09:58 2017 testlog-2017-03-07.13.09.log.20
2052 7 Mar 13:10:00 2017 testlog-2017-03-07.13.09.log.21
3078 7 Mar 13:10:05 2017 testlog-2017-03-07.13.10.log.1
3078 7 Mar 13:10:08 2017 testlog-2017-03-07.13.10.log.2
3078 7 Mar 13:10:11 2017 testlog-2017-03-07.13.10.log.3
3078 7 Mar 13:10:14 2017 testlog-2017-03-07.13.10.log.4
The example below will rotate files daily but each file will be limited to 5MB.
// Rotate every day or every 5 megabytes, whatever comes first.
var rotatingLogStream = require('file-stream-rotator').getStream(
{
filename:"/tmp/test-%DATE%.log",
frequency:"custom",
verbose: false,
date_format: "YYYY-MM-DD",
size: "5M" // its letter denominating the size is case insensitive
}
);
rotatingLogStream.on('rotate',function(oldFile,newFile){
// do something with old file like compression or delete older than X days.
})
NPM Maintainers
The npm module for this library will be maintained by:
License
file-stream-rotator is licensed under the MIT license.