file-timestamp-stream


This module creates
stream.Writable
to a file which is automatically rotated based on current time and uses
strftime template for file names.

Requirements

This module requires ES2021 with Node >= 16.

Installation

``shell
npm install file-timestamp-stream
`

_Additionally for Typescript:_

`shell
npm install -D @types/node
`

Usage

_Example:_

`js
import FileTimestampStream from "file-timestamp-stream"
// or
import {FileTimestampStream} from "file-timestamp-stream"
`

$3

- flags is a string with
flags
for the opened stream (default: 'a')
- fs is a custom fs module (optional)
- path is a template for new filenames (default: 'out.log')

_Example:_

Basic path based on strftime parameters:

`js
const stream = new FileTimestampStream({
path: "%Y-%m-%dT%H.log",
flags: "a",
})
`

$3

This method can be overridden in the subclass.

The method generates a filename for new files. By default, it returns a new
filename based on path and current time.

_Example:_

`ts
import strftime from "ultra-strftime"

class MyFileTimestampStream extends FileTimestampStream {
/* count how many files has been created /
counter = 0

// for pure Javascript explicit constructor is necessary
// constructor (options) { super(options); this.counter = 0 }

protected newFilename(): string {
const filename = strftime(this.path)
if (filename !== this.currentFilename) this.counter++
return filename
}
}

const stream = new MyFileTimestampStream({
path: "%Y-%m-%dT%H:%M.log",
})
`

$3

Readonly public properties based on contructor's options:

- flags
- fs
- path

Protected properties for a custom subclass:

- currentFilename contains the last opened filename
- stream` contains current
fs.WriteStream
object

$3

A path can contain strftime specifiers.

$3

This stream has to be closed to free streams and timers.

License

Copyright (c) 2017-2024 Piotr Roszatycki

MIT