fs-extra
adds file system methods that aren't included in the native fs
module. It is a drop in replacement for fs
.
Why?
I got tired of including mkdirp
, rimraf
, and cp -r
in most of my projects.
Installation
npm install --save fs-extra
Usage
fs-extra
is a drop in replacement for native fs
. All methods in fs
are unmodified and attached to fs-extra
.
You don't ever need to include the original fs
module again:
var fs = require('fs')
you can now do this:
var fs = require('fs-extra')
or if you prefer to make it clear that you're using fs-extra
and not fs
, you may want
to name your fs
variable fse
like so:
var fse = require('fs-extra')
you can also keep both, but it's redundant:
var fs = require('fs')
var fse = require('fs-extra')
Methods
NOTE: You can still use the native Node.js methods. They are copied over to fs-extra
.
copy()
copy(src, dest, [options], callback)
Copy a file or directory. The directory can have contents. Like cp -r
.
Options:
clobber (boolean): overwrite existing file or directory
preserveTimestamps (boolean): will set last modification and access times to the ones of the original source files, default is false
.
Sync: copySync()
Examples:
var fs = require('fs-extra')
fs.copy('/tmp/myfile', '/tmp/mynewfile', function (err) {
if (err) return console.error(err)
console.log("success!")
})
fs.copy('/tmp/mydir', '/tmp/mynewdir', function (err) {
if (err) return console.error(err)
console.log('success!')
})
createOutputStream(file, [options])
Exactly like createWriteStream
, but if the directory does not exist, it's created.
Examples:
var fs = require('fs-extra')
var ws = fs.createOutputStream('/tmp/some/file.txt')
ws.write('hello\n')
Note on naming: you'll notice that fs-extra has some methods like fs.outputJson
, fs.outputFile
, etc that use the
word output
to denote that if the containing directory does not exist, it should be created. If you can think of a
better succinct nomenclature for these methods, please open an issue for discussion. Thanks.
emptyDir(dir, [callback])
Ensures that a directory is empty. If the directory does not exist, it is created. The directory itself is not deleted.
Alias: emptydir()
Sync: emptyDirSync()
, emptydirSync()
Example:
var fs = require('fs-extra')
fs.emptyDir('/tmp/some/dir', function (err) {
if (!err) console.log('success!')
})
ensureFile(file, callback)
Ensures that the file exists. If the file that is requested to be created is in directories that do not exist, these directories are created. If the file already exists, it is NOT MODIFIED.
Alias: createFile()
Sync: createFileSync()
,ensureFileSync()
Example:
var fs = require('fs-extra')
var file = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureFile(file, function (err) {
console.log(err)
})
ensureDir(dir, callback)
Ensures that the directory exists. If the directory structure does not exist, it is created.
Sync: ensureDirSync()
Example:
var fs = require('fs-extra')
var dir = '/tmp/this/path/does/not/exist'
fs.ensureDir(dir, function (err) {
console.log(err)
})
ensureLink(srcpath, dstpath, callback)
Ensures that the link exists. If the directory structure does not exist, it is created.
Sync: ensureLinkSync()
Example:
var fs = require('fs-extra')
var srcpath = '/tmp/file.txt'
var dstpath = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureLink(srcpath, dstpath, function (err) {
console.log(err)
})
ensureSymlink(srcpath, dstpath, [type], callback)
Ensures that the symlink exists. If the directory structure does not exist, it is created.
Sync: ensureSymlinkSync()
Example:
var fs = require('fs-extra')
var srcpath = '/tmp/file.txt'
var dstpath = '/tmp/this/path/does/not/exist/file.txt'
fs.ensureSymlink(srcpath, dstpath, function (err) {
console.log(err)
})
mkdirs(dir, callback)
Creates a directory. If the parent hierarchy doesn't exist, it's created. Like mkdir -p
.
Alias: mkdirp()
Sync: mkdirsSync()
/ mkdirpSync()
Examples:
var fs = require('fs-extra')
fs.mkdirs('/tmp/some/long/path/that/prob/doesnt/exist', function (err) {
if (err) return console.error(err)
console.log("success!")
})
fs.mkdirsSync('/tmp/another/path')
move(src, dest, [options], callback)
Moves a file or directory, even across devices.
Options:
clobber (boolean): overwrite existing file or directory
limit (number): number of concurrent moves, see ncp for more information
Example:
var fs = require('fs-extra')
fs.move('/tmp/somefile', '/tmp/does/not/exist/yet/somefile', function (err) {
if (err) return console.error(err)
console.log("success!")
})
outputFile(file, data, callback)
Almost the same as writeFile
(i.e. it overwrites), except that if the parent directory does not exist, it's created.
Sync: outputFileSync()
Example:
var fs = require('fs-extra')
var file = '/tmp/this/path/does/not/exist/file.txt'
fs.outputFile(file, 'hello!', function (err) {
console.log(err)
fs.readFile(file, 'utf8', function (err, data) {
console.log(data)
})
})
outputJson(file, data, [options], callback)
Almost the same as writeJson
, except that if the directory does not exist, it's created.
options
are what you'd pass to jsonFile.writeFile()
.
Alias: outputJSON()
Sync: outputJsonSync()
, outputJSONSync()
Example:
var fs = require('fs-extra')
var file = '/tmp/this/path/does/not/exist/file.txt'
fs.outputJson(file, {name: 'JP'}, function (err) {
console.log(err)
fs.readJson(file, function(err, data) {
console.log(data.name)
})
})
readJson(file, [options], callback)
Reads a JSON file and then parses it into an object. options
are the same
that you'd pass to jsonFile.readFile
.
Alias: readJSON()
Sync: readJsonSync()
, readJSONSync()
Example:
var fs = require('fs-extra')
fs.readJson('./package.json', function (err, packageObj) {
console.log(packageObj.version)
})
readJsonSync()
can take a throws
option set to false
and it won't throw if the JSON is invalid. Example:
var fs = require('fs-extra')
var file = path.join('/tmp/some-invalid.json')
var data = '{not valid JSON'
fs.writeFileSync(file, data)
var obj = fs.readJsonSync(file, {throws: false})
console.log(obj)
remove(dir, callback)
Removes a file or directory. The directory can have contents. Like rm -rf
.
Sync: removeSync()
Examples:
var fs = require('fs-extra')
fs.remove('/tmp/myfile', function (err) {
if (err) return console.error(err)
console.log('success!')
})
fs.removeSync('/home/jprichardson')
writeJson(file, object, [options], callback)
Writes an object to a JSON file. options
are the same that
you'd pass to jsonFile.writeFile()
.
Alias: writeJSON()
Sync: writeJsonSync()
, writeJSONSync()
Example:
var fs = require('fs-extra')
fs.writeJson('./package.json', {name: 'fs-extra'}, function (err) {
console.log(err)
})
Third Party
Promises
Use Bluebird. See https://github.com/petkaantonov/bluebird/blob/master/API.md#promisification. fs-extra
is
explicitly listed as supported.
var Promise = require('bluebird')
var fs = Promise.promisifyAll(require('fs-extra'))
Or you can use the package fs-extra-promise
that marries the two together.
TypeScript
If you like TypeScript, you can use fs-extra
with it: https://github.com/borisyankov/DefinitelyTyped/tree/master/fs-extra
File / Directory Watching
If you want to watch for changes to files or directories, then you should use chokidar.
Misc.
- mfs - Monitor your fs-extra calls.
Wanna hack on fs-extra
? Great! Your help is needed! fs-extra is one of the most depended upon Node.js packages. This project
uses JavaScript Standard Style - if the name or style choices bother you,
you're gonna have to get over it :) If standard
is good enough for npm
, it's good enough for fs-extra
.
What's needed?
- First, take a look at existing issues. Those are probably going to be where the priority lies.
- More tests for edge cases. Specifically on different platforms. There can never be enough tests.
- Really really help with the Windows tests. See appveyor outputs for more info.
- Improve test coverage. See coveralls output for more info.
- A directory walker. Probably this one: https://github.com/thlorenz/readdirp imported into
fs-extra
. - After the directory walker is integrated, any function that needs to traverse directories like
copy
, remove
, or mkdirs
should be built on top of it. - After the aforementioned functions are built on the directory walker,
fs-extra
should then explicitly
support wildcards.
Note: If you make any big changes, you should definitely post an issue for discussion first.
Naming
I put a lot of thought into the naming of these functions. Inspired by @coolaj86's request. So he deserves much of the credit for raising the issue. See discussion(s) here:
First, I believe that in as many cases as possible, the Node.js naming schemes should be chosen. However, there are problems with the Node.js own naming schemes.
For example, fs.readFile()
and fs.readdir()
: the F is capitalized in File and the d is not capitalized in dir. Perhaps a bit pedantic, but they should still be consistent. Also, Node.js has chosen a lot of POSIX naming schemes, which I believe is great. See: fs.mkdir()
, fs.rmdir()
, fs.chown()
, etc.
We have a dilemma though. How do you consistently name methods that perform the following POSIX commands: cp
, cp -r
, mkdir -p
, and rm -rf
?
My perspective: when in doubt, err on the side of simplicity. A directory is just a hierarchical grouping of directories and files. Consider that for a moment. So when you want to copy it or remove it, in most cases you'll want to copy or remove all of its contents. When you want to create a directory, if the directory that it's suppose to be contained in does not exist, then in most cases you'll want to create that too.
So, if you want to remove a file or a directory regardless of whether it has contents, just call fs.remove(path)
. If you want to copy a file or a directory whether it has contents, just call fs.copy(source, destination)
. If you want to create a directory regardless of whether its parent directories exist, just call fs.mkdirs(path)
or fs.mkdirp(path)
.
Credit
fs-extra
wouldn't be possible without using the modules from the following authors:
License
Licensed under MIT
Copyright (c) 2011-2015 JP Richardson