TIL node modules fs and os

POSTED ON: Jan 04, 2023

TAGS: node streams os

Today I learned about the NodeJS OS module and folder structure

Working with folders in Node.js #

The Node.js fs core module provides many handy methods you can use to work with folders.

Use-cases:

• Use fs.access() to check if the folder exists and Node.js can access it with its permissions.

• fs.readFile() method to read the contents of a file and the fs.writeFile() method to write data to a file. These methods are useful for working with text files, JSON files, and other types of data.

• fs.mkdir() to create a new directory, fs.readdir() to list the contents of a directory, and fs.rmdir() to remove a directory.

• fs.watch() method, which allows you to monitor a file or directory for changes. When a change occurs, you can execute a callback function to perform some action, such as updating a cache or reloading a web page.

• fs.chmod() method allows you to set the permissions for a file or directory.

• fs.createReadStream() and fs.createWriteStream(). These methods are useful for working with large files or for streaming data over a network.

• fs.stat() method allows you to retrieve information about a file or directory, such as its size, last modified date, and file type.

via Node.js Files

The Node.js os module #

This module provides many functions that you can use to retrieve information from the underlying operating system and the computer the program runs on, and interact with it.

• Retrieving system information, such as the amount of free memory os.freemem(), the CPU architecture os.machine(), the hostname os.hostname(), and the operating system version os.version().

• os.cpus() to retrieve information about the system's CPUs, os.loadavg() to retrieve the system's load average, and os.uptime() to retrieve the system's uptime.

• os.userInfo([options]) Returns information about the currently effective user. On POSIX platforms, this is typically a subset of the password file. The returned object includes the username, uid, gid, shell, and homedir. On Windows, the uid and gid fields are -1, and shell is null.

• os.tmpdir() to retrieve the system's temporary directory and os.homedir() to retrieve the current user's home directory.
  via Node.js OS

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