# npm

node package manager

## SYNOPSIS

    var npm = require("npm")
    npm.load(configObject, function (er, npm) {
      // use the npm object, now that it's loaded.

      npm.config.set(key, val)
      val = npm.config.get(key)

      console.log("prefix = %s", npm.prefix)

      npm.commands.install(["package"], cb)
    })

## VERSION

1.1.49

## DESCRIPTION

This is the API documentation for npm. To find documentation of the command line client, see `npm(1)`.

Prior to using npm's commands, `npm.load()` must be called with an object hash of top-level configs. In the npm command line client, this set of configs is parsed from the command line options. Additional configuration params are loaded from two configuration files. See `config(1)` for more information.

After that, each of the functions are accessible in the commands object: `npm.commands.<cmd>`. See `index(1)` for a list of all possible commands.

All commands on the command object take an array of positional argument strings. The last argument to any function is a callback. Some commands take other optional arguments.

Configs cannot currently be set on a per function basis, as each call to npm.config.set will change the value for all npm commands in that process.

To find API documentation for a specific command, run the `npm apihelp` command.

## METHODS AND PROPERTIES

- `npm.load(configs, cb)`

  Load the configuration params, and call the `cb` function once the globalconfig and userconfig files have been loaded as well, or on nextTick if they've already been loaded.

- `npm.config`

  An object for accessing npm configuration parameters.

  - `npm.config.get(key)`

  - `npm.config.set(key, val)`

  - `npm.config.del(key)`

- `npm.dir` or `npm.root`

  The `node_modules` directory where npm will operate.

- `npm.prefix`

  The prefix where npm is operating. (Most often the current working directory.)

- `npm.cache`

  The place where npm keeps JSON and tarballs it fetches from the registry (or uploads to the registry).

- `npm.tmp`

  npm's temporary working directory.

- `npm.deref`

  Get the "real" name for a command that has either an alias or abbreviation.

## MAGIC

For each of the methods in the `npm.commands` hash, a method is added to the npm object, which takes a set of positional string arguments rather than an array and a callback.

If the last argument is a callback, then it will use the supplied callback. However, if no callback is provided, then it will print out the error or results.

For example, this would work in a node repl:

    > npm = require("npm")
    > npm.load()  // wait a sec...
    > npm.install("dnode", "express")

Note that that won't work in a node program, since the `install` method will get called before the configuration load is completed.

## ABBREVS

In order to support `npm ins foo` instead of `npm install foo`, the `npm.commands` object has a set of abbreviations as well as the full method names. Use the `npm.deref` method to find the real name.

For example:

    var cmd = npm.deref("unp") // cmd === "unpublish"