Determine command line working directory when runn

问题:

I am creating a node command line interface. It is installed globally and uses a bin file to execute.

I plan to have a command window open at the root directory of the files I am working on and then just run the command however I have been unable to determine the current working directory as process.cwd() is returning the directory of the node package. I initially assumed that since the code is being executed using a batch file as a wrapper (that is how bin files can execute without node at the beginning) then it is impossible but coffee-script manages to do it. I took a look at the coffee-script source but couldn't follow it (not experienced enough).

To test it for yourself create a package with this package.json file:

{
  "name": "test-package",
  "version": "1.0.0",
  "bin": {
    "test-package":  "./bin/test-package"
  },
  "main": "/lib/test"
}

this test-package file in bin:

#!/usr/bin/env node

var path = require('path');
var fs   = require('fs');
var lib  = path.join(path.dirname(fs.realpathSync(__filename)), '../lib');

require(lib + '/test');

Could anyone shed some light onto this.

and then try and get the command line directory inside lib/test.

回答1:

• process.cwd() returns directory where command has been executed (not directory of the node package) if it's has not been changed by 'process.chdir' inside of application.
• __filename returns absolute path to file where it is placed.
• __dirname returns absolute path to directory of __filename.

If you need to load files from your module directory you need to use relative paths.

require('../lib/test');

instead of

var lib  = path.join(path.dirname(fs.realpathSync(__filename)), '../lib');

require(lib + '/test');

It's always relative to file where it called from and don't depend on current work dir.

回答2:

Current Working Directory

To get the current working directory, you can use:

process.cwd()

However, be aware that some scripts, notably gulp, will change the current working directory with process.chdir().

Node Module Path

You can get the path of the current module with:

• __filename
• __dirname

Original Directory (where the command was initiated)

If you are running a script from the command line, and you want the original directory from which the script was run, regardless of what directory the script is currently operating in, you can use:

process.env.INIT_CWD

Original directory, when working with NPM scripts

It's sometimes desirable to run an NPM script in the current directory, rather than the root of the project.

This variable is available inside npm package scripts as:

$INIT_CWD.

You must be running a recent version of NPM. If this variable is not available, make sure NPM is up to date.

This will allow you access the current path in your package.json, e.g.:

scripts: {
  "customScript": "gulp customScript --path $INIT_CWD"
}

回答3:

Alternatively, if you want to solely obtain the current directory of the current NodeJS script, you could try something simple like this. Note that this will not work in the Node CLI itself:

var fs = require('fs'),
    path = require('path');

var dirString = path.dirname(fs.realpathSync(__filename));

// output example: "/Users/jb/workspace/abtest"
console.log('directory to start walking...', dirString);

回答4:

path.resolve('.') is also a reliable and clean option, because we almost always require('path'). It will give you absolute path of the directory from where it is called.