nodejs/doc/api/path.md

Path

Stability: 2 - Stable

This module contains utilities for handling and transforming file paths. The file system is not consulted to check whether paths are valid.

Use require('path') to use this module. The following methods are provided:

path.basename(path[, ext])

Return the last portion of a path, similar to the Unix basename command. path must be a string. ext, if given, must also be a string.

Examples:

path.basename('/foo/bar/baz/asdf/quux.html')
// returns 'quux.html'

path.basename('/foo/bar/baz/asdf/quux.html', '.html')
// returns 'quux'

path.delimiter

The platform-specific path delimiter, ; or ':'.

An example on *nix:

console.log(process.env.PATH)
// '/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin'

process.env.PATH.split(path.delimiter)
// returns ['/usr/bin', '/bin', '/usr/sbin', '/sbin', '/usr/local/bin']

An example on Windows:

console.log(process.env.PATH)
// 'C:\Windows\system32;C:\Windows;C:\Program Files\node\'

process.env.PATH.split(path.delimiter)
// returns ['C:\\Windows\\system32', 'C:\\Windows', 'C:\\Program Files\\node\\']

path.dirname(path)

Return the directory name of a path, similar to the Unix dirname command. path must be a string.

Example:

path.dirname('/foo/bar/baz/asdf/quux')
// returns '/foo/bar/baz/asdf'

path.extname(path)

Return the extension of the path, from the last '.' to end of string in the last portion of the path. If there is no '.' in the last portion of the path or the first character of it is '.', then it returns an empty string. path must be a string.

Examples:

path.extname('index.html')
// returns '.html'

path.extname('index.coffee.md')
// returns '.md'

path.extname('index.')
// returns '.'

path.extname('index')
// returns ''

path.extname('.index')
// returns ''

path.format(pathObject)

Returns a path string from an object. This is the opposite of path.parse.

If pathObject has dir and base properties, the returned string will be a concatenation of the dir property, the platform-dependent path separator, and the base property.

If the dir property is not supplied, the root property will be used as the dir property. However, it will be assumed that the root property already ends with the platform-dependent path separator. In this case, the returned string will be the concatenation of the root property and the base property.

If both the dir and the root properties are not supplied, then the returned string will be the contents of the base property.

If the base property is not supplied, a concatenation of the name property and the ext property will be used as the base property.

Examples:

Some Posix system examples:

// If `dir` and `base` are provided, `dir` + platform separator + `base`
// will be returned.
path.format({
    dir: '/home/user/dir',
    base: 'file.txt'
});
// returns '/home/user/dir/file.txt'

// `root` will be used if `dir` is not specified.
// `name` + `ext` will be used if `base` is not specified.
// If only `root` is provided or `dir` is equal to `root` then the
// platform separator will not be included.
path.format({
    root: '/',
    base: 'file.txt'
});
// returns '/file.txt'

path.format({
    dir: '/',
    root: '/',
    name: 'file',
    ext: '.txt'
});
// returns '/file.txt'

// `base` will be returned if `dir` or `root` are not provided.
path.format({
    base: 'file.txt'
});
// returns 'file.txt'

An example on Windows:

path.format({
    root : "C:\\",
    dir : "C:\\path\\dir",
    base : "file.txt",
    ext : ".txt",
    name : "file"
})
// returns 'C:\\path\\dir\\file.txt'

path.isAbsolute(path)

Determines whether path is an absolute path. An absolute path will always resolve to the same location, regardless of the working directory. path must be a string.

Examples on *nix:

path.isAbsolute('/foo/bar') // true
path.isAbsolute('/baz/..')  // true
path.isAbsolute('qux/')     // false
path.isAbsolute('.')        // false

Examples on Windows:

path.isAbsolute('//server')  // true
path.isAbsolute('C:/foo/..') // true
path.isAbsolute('bar\\baz')  // false
path.isAbsolute('.')         // false

Note: If the path string passed as parameter is a zero-length string, unlike other path module functions, it will be used as-is and false will be returned.

path.join([path1][, path2][, ...])

Join all arguments together and normalize the resulting path.

All arguments must be strings. In v0.8, non-string arguments were silently ignored. In v0.10 and up, an exception is thrown.

Examples:

path.join('/foo', 'bar', 'baz/asdf', 'quux', '..')
// returns '/foo/bar/baz/asdf'

path.join('foo', {}, 'bar')
// throws exception
TypeError: Arguments to path.join must be strings

Note: If the arguments to join have zero-length strings, unlike other path module functions, they will be ignored. If the joined path string is a zero-length string then '.' will be returned, which represents the current working directory.

path.normalize(path)

Normalize a path, taking care of '..' and '.' parts. path must be a string.

When multiple slashes are found, they're replaced by a single one; when the path contains a trailing slash, it is preserved. On Windows backslashes are used.

Example:

path.normalize('/foo/bar//baz/asdf/quux/..')
// returns '/foo/bar/baz/asdf'

Note: If the path string passed as argument is a zero-length string then '.' will be returned, which represents the current working directory.

path.parse(path)

Returns an object from a path. path must be a string.

An example on *nix:

path.parse('/home/user/dir/file.txt')
// returns
// {
//    root : "/",
//    dir : "/home/user/dir",
//    base : "file.txt",
//    ext : ".txt",
//    name : "file"
// }

An example on Windows:

path.parse('C:\\path\\dir\\index.html')
// returns
// {
//    root : "C:\\",
//    dir : "C:\\path\\dir",
//    base : "index.html",
//    ext : ".html",
//    name : "index"
// }

path.posix

Provide access to aforementioned path methods but always interact in a posix compatible way.

path.relative(from, to)

Solve the relative path from from to to. from and to must be strings.

At times we have two absolute paths, and we need to derive the relative path from one to the other. This is actually the reverse transform of path.resolve, which means we see that:

path.resolve(from, path.relative(from, to)) == path.resolve(to)

Examples:

path.relative('C:\\orandea\\test\\aaa', 'C:\\orandea\\impl\\bbb')
// returns '..\\..\\impl\\bbb'

path.relative('/data/orandea/test/aaa', '/data/orandea/impl/bbb')
// returns '../../impl/bbb'

Note: If the arguments to relative have zero-length strings then the current working directory will be used instead of the zero-length strings. If both the paths are the same then a zero-length string will be returned.

path.resolve([from ...], to)

Resolves to to an absolute path. All arguments must be strings.

If to isn't already absolute from arguments are prepended in right to left order, until an absolute path is found. If after using all from paths still no absolute path is found, the current working directory is used as well. The resulting path is normalized, and trailing slashes are removed unless the path gets resolved to the root directory. Empty string from arguments are ignored.

Another way to think of it is as a sequence of cd commands in a shell.

path.resolve('foo/bar', '/tmp/file/', '..', 'a/../subfile')

Is similar to:

cd foo/bar
cd /tmp/file/
cd ..
cd a/../subfile
pwd

The difference is that the different paths don't need to exist and may also be files.

Examples:

path.resolve('/foo/bar', './baz')
// returns '/foo/bar/baz'

path.resolve('/foo/bar', '/tmp/file/')
// returns '/tmp/file'

path.resolve('wwwroot', 'static_files/png/', '../gif/image.gif')
// if currently in /home/myself/node, it returns
// '/home/myself/node/wwwroot/static_files/gif/image.gif'

path.sep

The platform-specific file separator. '\\' or '/'.

An example on *nix:

'foo/bar/baz'.split(path.sep)
// returns ['foo', 'bar', 'baz']

An example on Windows:

'foo\\bar\\baz'.split(path.sep)
// returns ['foo', 'bar', 'baz']

path.win32

Provide access to aforementioned path methods but always interact in a win32 compatible way.