ShellJS is a portable (Windows/Linux/macOS) implementation of Unix shell commands on top of the Node.js API. You can use it to eliminate your shell script's dependency on Unix while still keeping its familiar and powerful commands. You can also install it globally so you can run it from outside Node projects - say goodbye to those gnarly Bash scripts!
ShellJS is proudly tested on every node release since v8
!
The project is unit-tested and battle-tested in projects like:
- Firebug - Firefox's infamous debugger
- JSHint & ESLint - popular JavaScript linters
- Zepto - jQuery-compatible JavaScript library for modern browsers
- Yeoman - Web application stack and development tool
- Deployd.com - Open source PaaS for quick API backend generation
- And many more.
If you have feedback, suggestions, or need help, feel free to post in our issue tracker.
Think ShellJS is cool? Check out some related projects in our Wiki page!
Upgrading from an older version? Check out our breaking changes page to see what changes to watch out for while upgrading.
If you just want cross platform UNIX commands, checkout our new project
shelljs/shx, a utility to expose shelljs
to
the command line.
For example:
$ shx mkdir -p foo
$ shx touch foo/bar.txt
$ shx rm -rf foo
ShellJS now supports third-party plugins! You can learn more about using plugins and writing your own ShellJS commands in the wiki.
For documentation on all the latest features, check out our README. To read docs that are consistent with the latest release, check out the npm page.
Via npm:
$ npm install [-g] shelljs
var shell = require('shelljs');
if (!shell.which('git')) {
shell.echo('Sorry, this script requires git');
shell.exit(1);
}
// Copy files to release dir
shell.rm('-rf', 'out/Release');
shell.cp('-R', 'stuff/', 'out/Release');
// Replace macros in each .js file
shell.cd('lib');
shell.ls('*.js').forEach(function (file) {
shell.sed('-i', 'BUILD_VERSION', 'v0.1.2', file);
shell.sed('-i', /^.*REMOVE_THIS_LINE.*$/, '', file);
shell.sed('-i', /.*REPLACE_LINE_WITH_MACRO.*\n/, shell.cat('macro.js'), file);
});
shell.cd('..');
// Run external tool synchronously
if (shell.exec('git commit -am "Auto-commit"').code !== 0) {
shell.echo('Error: Git commit failed');
shell.exit(1);
}
If you need to pass a parameter that looks like an option, you can do so like:
shell.grep('--', '-v', 'path/to/file'); // Search for "-v", no grep options
shell.cp('-R', '-dir', 'outdir'); // If already using an option, you're done
We no longer recommend using a global-import for ShellJS (i.e.
require('shelljs/global')
). While still supported for convenience, this
pollutes the global namespace, and should therefore only be used with caution.
Instead, we recommend a local import (standard for npm packages):
var shell = require('shelljs');
shell.echo('hello world');
Alternatively, we also support importing as a module with:
import shell from 'shelljs';
shell.echo('hello world');
All commands run synchronously, unless otherwise stated.
All commands accept standard bash globbing characters (*
, ?
, etc.),
compatible with the node glob
module.
For less-commonly used commands and features, please check out our wiki page.
Available options:
-n
: number all output lines
Examples:
var str = cat('file*.txt');
var str = cat('file1', 'file2');
var str = cat(['file1', 'file2']); // same as above
Returns a ShellString containing the given file, or a concatenated string containing the files if more than one file is given (a new line character is introduced between each file).
Changes to directory dir
for the duration of the script. Changes to home
directory if no argument is supplied. Returns a
ShellString to indicate success or failure.
Available options:
-v
: output a diagnostic for every file processed-c
: like verbose, but report only when a change is made-R
: change files and directories recursively
Examples:
chmod(755, '/Users/brandon');
chmod('755', '/Users/brandon'); // same as above
chmod('u+x', '/Users/brandon');
chmod('-R', 'a-w', '/Users/brandon');
Alters the permissions of a file or directory by either specifying the absolute permissions in octal form or expressing the changes in symbols. This command tries to mimic the POSIX behavior as much as possible. Notable exceptions:
- In symbolic modes,
a-r
and-r
are identical. No consideration is given to theumask
. - There is no "quiet" option, since default behavior is to run silent.
- Windows OS uses a very different permission model than POSIX.
chmod()
does its best on Windows, but there are limits to how file permissions can be set. Note that WSL (Windows subsystem for Linux) does follow POSIX, so cross-platform compatibility should not be a concern there.
Returns a ShellString indicating success or failure.
Available options:
-f
: force (default behavior)-n
: no-clobber-u
: only copy ifsource
is newer thandest
-r
,-R
: recursive-L
: follow symlinks-P
: don't follow symlinks-p
: preserve file mode, ownership, and timestamps
Examples:
cp('file1', 'dir1');
cp('-R', 'path/to/dir/', '~/newCopy/');
cp('-Rf', '/tmp/*', '/usr/local/*', '/home/tmp');
cp('-Rf', ['/tmp/*', '/usr/local/*'], '/home/tmp'); // same as above
Copies files. Returns a ShellString indicating success or failure.
Available options:
-n
: Suppresses the normal change of directory when adding directories to the stack, so that only the stack is manipulated.-q
: Suppresses output to the console.
Arguments:
dir
: Sets the current working directory to the top of the stack, then executes the equivalent ofcd dir
.+N
: Brings the Nth directory (counting from the left of the list printed by dirs, starting with zero) to the top of the list by rotating the stack.-N
: Brings the Nth directory (counting from the right of the list printed by dirs, starting with zero) to the top of the list by rotating the stack.
Examples:
// process.cwd() === '/usr'
pushd('/etc'); // Returns /etc /usr
pushd('+1'); // Returns /usr /etc
Save the current directory on the top of the directory stack and then cd
to dir
. With no arguments, pushd
exchanges the top two directories. Returns an array of paths in the stack.
Available options:
-n
: Suppress the normal directory change when removing directories from the stack, so that only the stack is manipulated.-q
: Supresses output to the console.
Arguments:
+N
: Removes the Nth directory (counting from the left of the list printed by dirs), starting with zero.-N
: Removes the Nth directory (counting from the right of the list printed by dirs), starting with zero.
Examples:
echo(process.cwd()); // '/usr'
pushd('/etc'); // '/etc /usr'
echo(process.cwd()); // '/etc'
popd(); // '/usr'
echo(process.cwd()); // '/usr'
When no arguments are given, popd
removes the top directory from the stack and performs a cd
to the new top directory. The elements are numbered from 0, starting at the first directory listed with dirs (i.e., popd
is equivalent to popd +0
). Returns an array of paths in the stack.
Available options:
-c
: Clears the directory stack by deleting all of the elements.-q
: Supresses output to the console.
Arguments:
+N
: Displays the Nth directory (counting from the left of the list printed by dirs when invoked without options), starting with zero.-N
: Displays the Nth directory (counting from the right of the list printed by dirs when invoked without options), starting with zero.
Display the list of currently remembered directories. Returns an array of paths in the stack, or a single path if +N
or -N
was specified.
See also: pushd
, popd
Available options:
-e
: interpret backslash escapes (default)-n
: remove trailing newline from output
Examples:
echo('hello world');
var str = echo('hello world');
echo('-n', 'no newline at end');
Prints string
to stdout, and returns a ShellString.
Available options:
async
: Asynchronous execution. If a callback is provided, it will be set totrue
, regardless of the passed value (default:false
).fatal
: Exit upon error (default:false
).silent
: Do not echo program output to console (default:false
).encoding
: Character encoding to use. Affects the values returned to stdout and stderr, and what is written to stdout and stderr when not in silent mode (default:'utf8'
).- and any option available to Node.js's
child_process.exec()
Examples:
var version = exec('node --version', {silent:true}).stdout;
var child = exec('some_long_running_process', {async:true});
child.stdout.on('data', function(data) {
/* ... do something with data ... */
});
exec('some_long_running_process', function(code, stdout, stderr) {
console.log('Exit code:', code);
console.log('Program output:', stdout);
console.log('Program stderr:', stderr);
});
Executes the given command
synchronously, unless otherwise specified.
When in synchronous mode, this returns a ShellString.
Otherwise, this returns the child process object, and the callback
receives the arguments (code, stdout, stderr)
.
Not seeing the behavior you want? exec()
runs everything through sh
by default (or cmd.exe
on Windows), which differs from bash
. If you
need bash-specific behavior, try out the {shell: 'path/to/bash'}
option.
Security note: as shell.exec()
executes an arbitrary string in the
system shell, it is critical to properly sanitize user input to avoid
command injection. For more context, consult the Security
Guidelines.
Examples:
find('src', 'lib');
find(['src', 'lib']); // same as above
find('.').filter(function(file) { return file.match(/\.js$/); });
Returns a ShellString (with array-like properties) of all files (however deep) in the given paths.
The main difference from ls('-R', path)
is that the resulting file names
include the base directories (e.g., lib/resources/file1
instead of just file1
).
Available options:
-v
: Invertregex_filter
(only print non-matching lines).-l
: Print only filenames of matching files.-i
: Ignore case.-n
: Print line numbers.
Examples:
grep('-v', 'GLOBAL_VARIABLE', '*.js');
grep('GLOBAL_VARIABLE', '*.js');
Reads input string from given files and returns a
ShellString containing all lines of the @ file that match
the given regex_filter
.
Available options:
-n <num>
: Show the first<num>
lines of the files
Examples:
var str = head({'-n': 1}, 'file*.txt');
var str = head('file1', 'file2');
var str = head(['file1', 'file2']); // same as above
Read the start of a file
. Returns a ShellString.
Available options:
-s
: symlink-f
: force
Examples:
ln('file', 'newlink');
ln('-sf', 'file', 'existing');
Links source
to dest
. Use -f
to force the link, should dest
already
exist. Returns a ShellString indicating success or
failure.
Available options:
-R
: recursive-A
: all files (include files beginning with.
, except for.
and..
)-L
: follow symlinks-d
: list directories themselves, not their contents-l
: provides more details for each file. Specifically, each file is represented by a structured object with separate fields for file metadata (seefs.Stats
). The return value also overrides.toString()
to resemblels -l
's output format for human readability, but programmatic usage should depend on the stable object format rather than the.toString()
representation.
Examples:
ls('projs/*.js');
ls('projs/**/*.js'); // Find all js files recursively in projs
ls('-R', '/users/me', '/tmp');
ls('-R', ['/users/me', '/tmp']); // same as above
ls('-l', 'file.txt'); // { name: 'file.txt', mode: 33188, nlink: 1, ...}
Returns a ShellString (with array-like properties) of all
the files in the given path
, or files in the current directory if no
path
is provided.
Available options:
-p
: full path (and create intermediate directories, if necessary)
Examples:
mkdir('-p', '/tmp/a/b/c/d', '/tmp/e/f/g');
mkdir('-p', ['/tmp/a/b/c/d', '/tmp/e/f/g']); // same as above
Creates directories. Returns a ShellString indicating success or failure.
Available options:
-f
: force (default behavior)-n
: no-clobber
Examples:
mv('-n', 'file', 'dir/');
mv('file1', 'file2', 'dir/');
mv(['file1', 'file2'], 'dir/'); // same as above
Moves source
file(s) to dest
. Returns a ShellString
indicating success or failure.
Returns the current directory as a ShellString.
Available options:
-f
: force-r, -R
: recursive
Examples:
rm('-rf', '/tmp/*');
rm('some_file.txt', 'another_file.txt');
rm(['some_file.txt', 'another_file.txt']); // same as above
Removes files. Returns a ShellString indicating success or failure.
Available options:
-i
: Replace contents offile
in-place. Note that no backups will be created!
Examples:
sed('-i', 'PROGRAM_VERSION', 'v0.1.3', 'source.js');
Reads an input string from file
s, line by line, and performs a JavaScript replace()
on
each of the lines from the input string using the given search_regex
and replacement
string or
function. Returns the new ShellString after replacement.
Note:
Like unix sed
, ShellJS sed
supports capture groups. Capture groups are specified
using the $n
syntax:
sed(/(\w+)\s(\w+)/, '$2, $1', 'file.txt');
Also, like unix sed
, ShellJS sed
runs replacements on each line from the input file
(split by '\n') separately, so search_regex
es that span more than one line (or inlclude '\n')
will not match anything and nothing will be replaced.
Available options:
+/-e
: exit upon error (config.fatal
)+/-v
: verbose: show all commands (config.verbose
)+/-f
: disable filename expansion (globbing)
Examples:
set('-e'); // exit upon first error
set('+e'); // this undoes a "set('-e')"
Sets global configuration variables.
Available options:
-r
: Reverse the results-n
: Compare according to numerical value
Examples:
sort('foo.txt', 'bar.txt');
sort('-r', 'foo.txt');
Return the contents of the file
s, sorted line-by-line as a
ShellString. Sorting multiple files mixes their content
(just as unix sort
does).
Available options:
-n <num>
: Show the last<num>
lines offile
s
Examples:
var str = tail({'-n': 1}, 'file*.txt');
var str = tail('file1', 'file2');
var str = tail(['file1', 'file2']); // same as above
Read the end of a file
. Returns a ShellString.
Examples:
var tmp = tempdir(); // "/tmp" for most *nix platforms
Searches and returns string containing a writeable, platform-dependent temporary directory. Follows Python's tempfile algorithm.
Available expression primaries:
'-b', 'path'
: true if path is a block device'-c', 'path'
: true if path is a character device'-d', 'path'
: true if path is a directory'-e', 'path'
: true if path exists'-f', 'path'
: true if path is a regular file'-L', 'path'
: true if path is a symbolic link'-p', 'path'
: true if path is a pipe (FIFO)'-S', 'path'
: true if path is a socket
Examples:
if (test('-d', path)) { /* do something with dir */ };
if (!test('-f', path)) continue; // skip if it's not a regular file
Evaluates expression
using the available primaries and returns
corresponding boolean value.
Examples:
cat('input.txt').to('output.txt');
Analogous to the redirection operator >
in Unix, but works with
ShellStrings
(such as those returned by cat
, grep
, etc.). Like Unix
redirections, to()
will overwrite any existing file! Returns the same
ShellString this operated on, to support chaining.
Examples:
cat('input.txt').toEnd('output.txt');
Analogous to the redirect-and-append operator >>
in Unix, but works with
ShellStrings
(such as those returned by cat
, grep
, etc.). Returns the
same ShellString this operated on, to support chaining.
Available options:
-a
: Change only the access time-c
: Do not create any files-m
: Change only the modification time{'-d': someDate}
,{date: someDate}
: Use aDate
instance (ex.someDate
) instead of current time{'-r': file}
,{reference: file}
: Usefile
's times instead of current time
Examples:
touch('source.js');
touch('-c', 'path/to/file.js');
touch({ '-r': 'referenceFile.txt' }, 'path/to/file.js');
touch({ '-d': new Date('December 17, 1995 03:24:00'), '-m': true }, 'path/to/file.js');
touch({ date: new Date('December 17, 1995 03:24:00') }, 'path/to/file.js');
Update the access and modification times of each file to the current time.
A file argument that does not exist is created empty, unless -c
is supplied.
This is a partial implementation of
touch(1)
. Returns a
ShellString indicating success or failure.
Available options:
-i
: Ignore case while comparing-c
: Prefix lines by the number of occurrences-d
: Only print duplicate lines, one for each group of identical lines
Examples:
uniq('foo.txt');
uniq('-i', 'foo.txt');
uniq('-cd', 'foo.txt', 'bar.txt');
Filter adjacent matching lines from input
. Returns a
ShellString.
Examples:
var nodeExec = which('node');
Searches for command
in the system's PATH
. On Windows, this uses the
PATHEXT
variable to append the extension if it's not already executable.
Returns a ShellString containing the absolute path to
command
.
Exits the current process with the given exit code
.
Tests if error occurred in the last command. Returns a truthy value if an error returned, or a falsy value otherwise.
Note: do not rely on the
return value to be an error message. If you need the last error message, use
the .stderr
attribute from the last command's return value instead.
Returns the error code from the last command.
Examples:
var foo = new ShellString('hello world');
This is a dedicated type returned by most ShellJS methods, which wraps a
string (or array) value. This has all the string (or array) methods, but
also exposes extra methods: .to()
,
.toEnd()
, and all the pipe-able methods
(ex. .cat()
, .grep()
, etc.). This can be easily converted into a string
by calling .toString()
.
This type also exposes the corresponding command's stdout, stderr, and
return status code via the .stdout
(string), .stderr
(string), and
.code
(number) properties respectively.
Object containing environment variables (both getter and setter). Shortcut
to process.env
.
Examples:
grep('foo', 'file1.txt', 'file2.txt').sed(/o/g, 'a').to('output.txt');
echo('files with o\'s in the name:\n' + ls().grep('o'));
cat('test.js').exec('node'); // pipe to exec() call
Commands can send their output to another command in a pipe-like fashion.
sed
, grep
, cat
, exec
, to
, and toEnd
can appear on the right-hand
side of a pipe. Pipes can be chained.
Example:
var sh = require('shelljs');
var silentState = sh.config.silent; // save old silent state
sh.config.silent = true;
/* ... */
sh.config.silent = silentState; // restore old silent state
Suppresses all command output if true
, except for echo()
calls.
Default is false
.
Example:
require('shelljs/global');
config.fatal = true; // or set('-e');
cp('this_file_does_not_exist', '/dev/null'); // throws Error here
/* more commands... */
If true
, the script will throw a Javascript error when any shell.js
command encounters an error. Default is false
. This is analogous to
Bash's set -e
.
Example:
config.verbose = true; // or set('-v');
cd('dir/');
rm('-rf', 'foo.txt', 'bar.txt');
exec('echo hello');
Will print each command as follows:
cd dir/
rm -rf foo.txt bar.txt
exec echo hello
Example:
config.globOptions = {nodir: true};
Use this value for calls to glob.sync()
instead of the default options.
Example:
var shell = require('shelljs');
// Make changes to shell.config, and do stuff...
/* ... */
shell.config.reset(); // reset to original state
// Do more stuff, but with original settings
/* ... */
Reset shell.config
to the defaults:
{
fatal: false,
globOptions: {},
maxdepth: 255,
noglob: false,
silent: false,
verbose: false,
}
Nate Fischer | Brandon Freitag |