# 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

1.4.28

## 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. If you provide `configObject` as an object hash of top-level configs, they override the values stored in the various config locations. 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 `npm-config(1)`, `npm-config(7)`, and `npmrc(5)` for more information.

After that, each of the functions are accessible in the commands object: `npm.commands.<cmd>`. See `npm-index(7)` 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"