file-timestamp-stream

file-timestamp-stream

This module creates stream.Writable to a file which is automatically rotated based on current time.

Requirements

This module requires ES6 with Node >= 6.

Installation

npm install file-timestamp-stream

Additionally for Typescript:

npm install -D @types/node

Transpiling this module with own settings in tsconfig.json:

{
  "compilerOptions": {
    "paths": {
      "file-timestamp-stream": ["node_modules/file-timestamp-stream/src/file-timestamp-stream"]
    }
  }
}

Usage

Example:

const { FileTimestampStream } = require('file-timestamp-stream')

Typescript:

import FileTimestampStream from 'file-timestamp-stream'

Options

• newFilename is a custom function with this object as an only argument which returns new filename (default: returns new filename based on path and current time)
• flags is a string with flags for 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:

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

Custom filename generator:

const strftime = require('ultra-strftime')

// count how many files was created
let counter = 0

const stream = new FileTimestampStream({
  path: '%Y-%m-%dT%H:%M.log',
  newFilename
})

function newFilename (fileTimestampStream) {
  const filename = strftime(fileTimestampStream.path)
  if (filename !== fileTimestampStream.currentFilename) counter++
  return filename
}

Properties

• currentFilename contains last opened filename
• stream contains fs.WriteStream object

Path template format

Path can contain strftime specifiers.

License

Copyright (c) 2017-2018 Piotr Roszatycki piotr.roszatycki@gmail.com

MIT