Ubuntu Manpage: npm-developers

name
description
about these documents
what is a package
the package.json file
keeping files out of your package
link packages
before publishing: make sure your package installs and works
create a user account
publish your package
brag about it
see also

NAME

       npm-developers - Developer Guide

DESCRIPTION

       So, you´ve decided to use npm to develop (and maybe publish/deploy) your project.

       Fantastic!

       There are a few things that you need to do above the simple steps that your users will do to install your
       program.

About These Documents

       These are man pages. If you install npm, you should  be  able  to  then  do  man  npm-thing  to  get  the
       documentation on a particular topic, or npm help thing to see the same information.

What is a <code>package</code>

       A package is:

       •   a) a folder containing a program described by a package.json file

       •   b) a gzipped tarball containing (a)

       •   c) a url that resolves to (b)

       •   d) a <name>@<version> that is published on the registry with (c)

       •   e) a <name>@<tag> that points to (d)

       •   f) a <name> that has a "latest" tag satisfying (e)

       •   g) a git url that, when cloned, results in (a).

       Even if you never publish your package, you can still get a lot of benefits of using npm if you just want
       to write a node program (a), and perhaps if you also want to be able to easily install it elsewhere after
       packing it up into a tarball (b).

       Git urls can be of the form:

           git://github.com/user/project.git#commit-ish
           git+ssh://user@hostname:project.git#commit-ish
           git+http://user@hostname/project/blah.git#commit-ish
           git+https://user@hostname/project/blah.git#commit-ish

       The  commit-ish  can be any tag, sha, or branch which can be supplied as an argument to git checkout. The
       default is master.

The package.json File

You need to have a package.json file in the root of your project to do much of anything with npm. That is
basically the whole interface.

See npm help 5 package.json for details about what goes in that file. At the very least, you need:

name This should be a string that identifies your project. Please do not use the name to specify that
it runs on node, or is in JavaScript. You can use the "engines" field to explicitly state the
versions of node (or whatever else) that your program requires, and it´s pretty well assumed that
it´s javascript.

It does not necessarily need to match your github repository name.

So, node-foo and bar-js are bad names. foo or bar are better.

version
A semver-compatible version.

engines
Specify the versions of node (or whatever else) that your program runs on. The node API changes a
lot, and there may be bugs or new functionality that you depend on. Be explicit.

author Take some credit.

scripts
If you have a special compilation or installation script, then you should put it in the scripts
object. You should definitely have at least a basic smoke-test command as the "scripts.test"
field. See npm help 7 scripts.

main If you have a single module that serves as the entry point to your program (like what the "foo"
package gives you at require("foo")), then you need to specify that in the "main" field.

directories
This is an object mapping names to folders. The best ones to include are "lib" and "doc", but if
you use "man" to specify a folder full of man pages, they´ll get installed just like these ones.

You can use npm init in the root of your package in order to get you started with a pretty basic
package.json file. See npm help npm-init for more info.

Keeping files <em>out</em> of your package

       Use a .npmignore file to keep stuff out of your package. If there´s no .npmignore file, but  there  is  a
       .gitignore  file,  then  npm will ignore the stuff matched by the .gitignore file. If you want to include
       something that is excluded by your .gitignore file, you can create an empty .npmignore file  to  override
       it.  Like  git,  npm looks for .npmignore and .gitignore files in all subdirectories of your package, not
       only the root directory.

       .npmignore          files           follow           the           same           pattern           rules
       http://git-scm.com/book/en/v2/Git-Basics-Recording-Changes-to-the-Repository#Ignoring-Files as .gitignore
       files:

       •   Blank lines or lines starting with # are ignored.

       •   Standard glob patterns work.

       •   You can end patterns with a forward slash / to specify a directory.

       •   You can negate a pattern by starting it with an exclamation point !.

       By default, the following paths and files are ignored, so there´s no  need  to  add  them  to  .npmignore
       explicitly:

       •   .*.swp

       •   ._*

       •   .DS_Store

       •   .git

       •   .hg

       •   .npmrc

       •   .lock-wscript

       •   .svn

       •   .wafpickle-*

       •   config.gypi

       •   CVS

       •   npm-debug.log

       Additionally,  everything  in node_modules is ignored, except for bundled dependencies. npm automatically
       handles this for you, so don´t bother adding node_modules to .npmignore.

       The following paths and files are never ignored, so adding them to .npmignore is pointless:

       •   package.json

       •   README (and its variants)

       •   CHANGELOG (and its variants)

       •   LICENSE / LICENCE

Link Packages

       npm link is designed to install a development package and see the changes in real time without having  to
       keep  re-installing  it. (You do need to either re-link or npm rebuild -g to update compiled packages, of
       course.)

       More info at npm help npm-link.

Before Publishing: Make Sure Your Package Installs and Works

       This is important.

       If you can not install it locally, you´ll have problems trying to publish it. Or, worse  yet,  you´ll  be
       able to publish it, but you´ll be publishing a broken or pointless package. So don´t do that.

       In the root of your package, do this:

           npm install . -g

       That´ll  show  you  that  it´s working. If you´d rather just create a symlink package that points to your
       working directory, then do this:

           npm link

       Use npm ls -g to see if it´s there.

       To test a local install, go into some other folder, and then do:

           cd ../some-other-folder
           npm install ../my-package

       to install it locally into the node_modules folder in that other place.

       Then go into the node-repl, and try using require("my-thing") to bring in your module´s main module.

Create a User Account

       Create a user with the adduser command. It works like this:

           npm adduser

       and then follow the prompts.

       This is documented better in npm help adduser.

Publish your package

       This part´s easy. In the root of your folder, do this:

           npm publish

       You can give publish a url to a tarball, or a filename of a tarball, or a path to a folder.

       Note that pretty much everything in that folder will be exposed by default. So, if you have secret  stuff
       in there, use a .npmignore file to list out the globs to ignore, or publish from a fresh checkout.

Brag about it

       Send emails, write blogs, blab in IRC.

       Tell the world how easy it is to install your program!