Node File Paths
How to interact with file paths and manipulate them in Node
Every file in the system has a path.
On Linux and macOS, a path might look like:
/users/flavio/file.txt
while Windows computers are different, and have a structure such as:
C:\users\flavio\file.txt
You need to pay attention when using paths in your applications, as this difference must be taken into account.
You include this module in your files using
const path = require('path')
and you can start using its methods.
Getting information out of a path
Given a path, you can extract information out of it using those methods:
dirname
: get the parent folder of a filebasename
: get the filename partextname
: get the file extension
Example:
const notes = '/users/flavio/notes.txt'
path.dirname(notes) // /users/flavio
path.basename(notes) // notes.txt
path.extname(notes) // .txt
You can get the file name without the extension by specifying a second argument to basename
:
path.basename(notes, path.extname(notes)) //notes
Working with paths
You can join two or more parts of a path by using path.join()
:
const name = 'flavio'
path.join('/', 'users', name, 'notes.txt') //'/users/flavio/notes.txt'
You can get the absolute path calculation of a relative path using path.resolve()
:
path.resolve('flavio.txt') //'/Users/flavio/flavio.txt' if run from my home folder
In this case Node will append /flavio.txt
to the current working directory. If you specify a second parameter folder, resolve
will use the first as a base for the second:
path.resolve('tmp', 'flavio.txt')//'/Users/flavio/tmp/flavio.txt' if run from my home folder
If the first parameter starts with a slash, that means it’s an absolute path:
path.resolve('/etc', 'flavio.txt')//'/etc/flavio.txt'
path.normalize()
is another useful function, that will try and calculate the actual path, when it contains relative specifiers like .
or ..
, or double slashes:
path.normalize('/users/flavio/..//test.txt') ///users/test.txt
Both resolve and normalize will not check if the path exists. They just calculate a path based on the information they got.
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