npm-install - Install a package
npm install (with no args, in package dir)
npm install [<@scope>/]<name>
npm install [<@scope>/]<name>@<tag>
npm install [<@scope>/]<name>@<version>
npm install [<@scope>/]<name>@<version range>
npm install <git-host>:<git-user>/<repo-name>
npm install <git repo url>
npm install <tarball file>
npm install <tarball url>
npm install <folder>
alias: npm i
common options: [-P|--save-prod|-D|--save-dev|-O|--save-optional] [-E|--save-exact] [-B|--save-bundle] [--no-save] [--dry-run]
This command installs a package, and any packages that it depends on. If the
package has a package-lock or shrinkwrap file, the installation of
dependencies will be driven by that, with an
npm-shrinkwrap.json taking
precedence if both files exist. See npm help 5 package-lock.json and npm help
shrinkwrap.
A
package is:
- •
- a) a folder containing a program described by a npm help 5
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
(see npm help 7 npm-registry) with (c)
- •
- e) a <name>@<tag> (see npm help npm-dist-tag)
that points to (d)
- •
- f) a <name> that has a "latest" tag satisfying
(e)
- •
- g) a <git remote url> that resolves to (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).
- •
- npm install (in package directory, no arguments):
Install the dependencies in the local node_modules folder.
In global mode (ie, with -g or --global appended to the
command),
it installs the current package context (ie, the current working
directory) as a global package.
By default, npm install will install all modules listed as
dependencies
in npm help 5 package.json.
With the --production flag (or when the NODE_ENV environment
variable
is set to production), npm will not install modules listed in
devDependencies. NOTE: The --production flag has no
particular meaning when adding a
dependency to a project.
- •
- npm install <folder>:
Install the package in the directory as a symlink in the current project.
Its dependencies will be installed before it's linked. If
<folder> sits
inside the root of your project, its dependencies may be hoisted to the
toplevel node_modules as they would for other types of
dependencies.
- •
- npm install <tarball file>:
Install a package that is sitting on the filesystem. Note: if you just want
to link a dev directory into your npm root, you can do this more easily by
using npm link.
Tarball requirements:
- •
- The filename must use .tar, .tar.gz, or .tgz
as the extension.
- •
- The package contents should reside in a subfolder inside the tarball
(usually it is called package/). npm strips one directory layer
when installing the package (an equivalent of tar x
--strip-components=1 is run).
- •
- The package must contain a package.json file with name and
version properties. Example:
npm install ./package.tgz
- •
- npm install <tarball url>:
Fetch the tarball url, and then install it. In order to distinguish between
this and other options, the argument must start with "http://" or
"https://"
Example:
npm install https://github.com/indexzero/forever/tarball/v0.5.6
- •
- npm install [<@scope>/]<name>:
Do a <name>@<tag> install, where <tag> is
the "tag" config. (See
npm help 7 npm-config. The config's default value is latest.)
In most cases, this will install the version of the modules tagged as
latest on the npm registry.
Example:
npm install saves any specified packages into
dependencies by
default.
Additionally, you can control where and how they get saved with some
additional flags:
- •
- -P, --save-prod: Package will appear in your dependencies.
This is the
default unless `-D` or `-O` are present.
- •
- -D, --save-dev: Package will appear in your
devDependencies.
- •
- -O, --save-optional: Package will appear in your
optionalDependencies.
- •
- --no-save: Prevents saving to dependencies. When using any
of the above options to save dependencies to your package.json, there are
two additional, optional flags:
- •
- -E, --save-exact: Saved dependencies will be configured with an
exact version rather than using npm's default semver range operator.
- •
- -B, --save-bundle: Saved dependencies will also be added to your
bundleDependencies list. Further, if you have an
npm-shrinkwrap.json or package-lock.json then it will be
updated as well. <scope> is optional. The package will be
downloaded from the registry associated with the specified scope. If no
registry is associated with the given scope the default registry is
assumed. See npm help 7 npm-scope. Note: if you do not include the
@-symbol on your scope name, npm will interpret this as a GitHub
repository instead, see below. Scopes names must also be followed by a
slash. Examples:
npm install sax
npm install githubname/reponame
npm install @myorg/privatepackage
npm install node-tap --save-dev
npm install dtrace-provider --save-optional
npm install readable-stream --save-exact
npm install ansi-regex --save-bundle
**Note**: If there is a file or folder named `<name>` in the current
working directory, then it will try to install that, and only try to
fetch the package by name if it is not valid.
- •
- npm install [<@scope>/]<name>@<tag>:
Install the version of the package that is referenced by the specified tag.
If the tag does not exist in the registry data for that package, then this
will fail.
Example:
npm install sax@latest
npm install @myorg/mypackage@latest
- •
- npm install [<@scope>/]<name>@<version>:
Install the specified version of the package. This will fail if the
version has not been published to the registry.
Example:
npm install sax@0.1.1
npm install @myorg/privatepackage@1.5.0
- •
- npm install [<@scope>/]<name>@<version range>:
Install a version of the package matching the specified version range. This
will follow the same rules for resolving dependencies described in npm help
5 package.json.
Note that most version ranges must be put in quotes so that your shell will
treat it as a single argument.
Example:
npm install sax@">=0.1.0 <0.2.0"
npm install @myorg/privatepackage@">=0.1.0 <0.2.0"
- •
- npm install <git remote url>:
Installs the package from the hosted git provider, cloning it with
git.
For a full git remote url, only that URL will be attempted.
<protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>[#<commit-ish> | #semver:<semver>]
<protocol> is one of
git,
git+ssh,
git+http,
git+https, or
git+file.
If
#<commit-ish> is provided, it will be used to clone exactly
that
commit. If the commit-ish has the format
#semver:<semver>,
<semver> can
be any valid semver range or exact version, and npm will look for any tags
or refs matching that range in the remote repository, much as it would for a
registry dependency. If neither
#<commit-ish> or
#semver:<semver> is
specified, then
master is used.
If the repository makes use of submodules, those submodules will be cloned
as well.
If the package being installed contains a
prepare script, its
dependencies and
devDependencies will be installed, and the
prepare
script will be run, before the package is packaged and installed.
The following git environment variables are recognized by npm and will be
added to the environment when running git:
- •
- GIT_ASKPASS
- •
- GIT_EXEC_PATH
- •
- GIT_PROXY_COMMAND
- •
- GIT_SSH
- •
- GIT_SSH_COMMAND
- •
- GIT_SSL_CAINFO
- •
- GIT_SSL_NO_VERIFY See the git man page for details. Examples:
npm install git+ssh://git@github.com:npm/cli.git#v1.0.27
npm install git+ssh://git@github.com:npm/cli#semver:^5.0
npm install git+https://isaacs@github.com/npm/cli.git
npm install git://github.com/npm/cli.git#v1.0.27
GIT_SSH_COMMAND='ssh -i ~/.ssh/custom_ident' npm install git+ssh://git@github.com:npm/cli.git
- •
- npm install
<githubname>/<githubrepo>[#<commit-ish>]:
- •
- npm install
github:<githubname>/<githubrepo>[#<commit-ish>]:
Install the package at https://github.com/githubname/githubrepo by
attempting to clone it using git.
If #<commit-ish> is provided, it will be used to clone exactly
that
commit. If the commit-ish has the format #semver:<semver>,
<semver> can
be any valid semver range or exact version, and npm will look for any tags
or refs matching that range in the remote repository, much as it would for
a
registry dependency. If neither #<commit-ish> or
#semver:<semver> is
specified, then master is used.
As with regular git dependencies, dependencies and
devDependencies will
be installed if the package has a prepare script, before the package
is
done installing.
Examples:
npm install mygithubuser/myproject
npm install github:mygithubuser/myproject
- •
- npm install
gist:[<githubname>/]<gistID>[#<commit-ish>|#semver:<semver>]:
Install the package at https://gist.github.com/gistID by attempting
to
clone it using git. The GitHub username associated with the gist is
optional and will not be saved in package.json.
As with regular git dependencies, dependencies and
devDependencies will
be installed if the package has a prepare script, before the package
is
done installing.
Example:
npm install gist:101a11beef
- •
- npm install
bitbucket:<bitbucketname>/<bitbucketrepo>[#<commit-ish>]:
Install the package at
https://bitbucket.org/bitbucketname/bitbucketrepo
by attempting to clone it using git.
If #<commit-ish> is provided, it will be used to clone exactly
that
commit. If the commit-ish has the format #semver:<semver>,
<semver> can
be any valid semver range or exact version, and npm will look for any tags
or refs matching that range in the remote repository, much as it would for
a
registry dependency. If neither #<commit-ish> or
#semver:<semver> is
specified, then master is used.
As with regular git dependencies, dependencies and
devDependencies will
be installed if the package has a prepare script, before the package
is
done installing.
Example:
npm install bitbucket:mybitbucketuser/myproject
- •
- npm install
gitlab:<gitlabname>/<gitlabrepo>[#<commit-ish>]:
Install the package at https://gitlab.com/gitlabname/gitlabrepo
by attempting to clone it using git.
If #<commit-ish> is provided, it will be used to clone exactly
that
commit. If the commit-ish has the format #semver:<semver>,
<semver> can
be any valid semver range or exact version, and npm will look for any tags
or refs matching that range in the remote repository, much as it would for
a
registry dependency. If neither #<commit-ish> or
#semver:<semver> is
specified, then master is used.
As with regular git dependencies, dependencies and
devDependencies will
be installed if the package has a prepare script, before the package
is
done installing.
Example:
npm install gitlab:mygitlabuser/myproject
npm install gitlab:myusr/myproj#semver:^5.0
You may combine multiple arguments, and even multiple types of arguments. For
example:
npm install sax@">=0.1.0 <0.2.0" bench supervisor
The
--tag argument will apply to all of the specified install targets. If
a tag with the given name exists, the tagged version is preferred over newer
versions.
The
--dry-run argument will report in the usual way what the install
would have done without actually installing anything.
The
--package-lock-only argument will only update the
package-lock.json, instead of checking
node_modules and
downloading dependencies.
The
-f or
--force argument will force npm to fetch remote
resources even if a local copy exists on disk.
The
-g or
--global argument will cause npm to install the package
globally rather than locally. See npm help 5
npm-folders.
The
--global-style argument will cause npm to install the package into
your local
node_modules folder with the same layout it uses with the
global
node_modules folder. Only your direct dependencies will show in
node_modules and everything they depend on will be flattened in their
node_modules folders. This obviously will eliminate some deduping.
The
--ignore-scripts argument will cause npm to not execute any scripts
defined in the package.json. See npm help 7
npm-scripts.
The
--legacy-bundling argument will cause npm to install the package such
that versions of npm prior to 1.4, such as the one included with node 0.8, can
install the package. This eliminates all automatic deduping.
The
--link argument will cause npm to link global installs into the local
space in some cases.
The
--no-bin-links argument will prevent npm from creating symlinks for
any binaries the package might contain.
The
--no-optional argument will prevent optional dependencies from being
installed.
The
--no-shrinkwrap argument, which will ignore an available package lock
or shrinkwrap file and use the package.json instead.
The
--no-package-lock argument will prevent npm from creating a
package-lock.json file. When running with package-lock's disabled npm
will not automatically prune your node modules when installing.
The
--nodedir=/path/to/node/source argument will allow npm to find the
node source code so that npm can compile native modules.
The
--only={prod[uction]|dev[elopment]} argument will cause either only
devDependencies or only non-
devDependencies to be installed
regardless of the
NODE_ENV.
The
--no-audit argument can be used to disable sending of audit reports
to the configured registries. See npm help
npm-audit for details on
what is sent.
See npm help 7
npm-config. Many of the configuration params have some
effect on installation, since that's most of what npm does.
To install a package, npm uses the following algorithm:
load the existing node_modules tree from disk
clone the tree
fetch the package.json and assorted metadata and add it to the clone
walk the clone and add any missing dependencies
dependencies will be added as close to the top as is possible
without breaking any other modules
compare the original tree with the cloned tree and make a list of
actions to take to convert one to the other
execute all of the actions, deepest first
kinds of actions are install, update, remove and move
For this
package{dep} structure:
A{B,C}, B{C}, C{D}, this
algorithm produces:
That is, the dependency from B to C is satisfied by the fact that A already
caused C to be installed at a higher level. D is still installed at the top
level because nothing conflicts with it.
For
A{B,C}, B{C,D@1}, C{D@2}, this algorithm produces:
A
+-- B
+-- C
`-- D@2
+-- D@1
Because B's D@1 will be installed in the top level, C now has to install D@2
privately for itself. This algorithm is deterministic, but different trees may
be produced if two dependencies are requested for installation in a different
order.
See npm help 5 folders for a more detailed description of the specific folder
structures that npm creates.
npm will refuse to install any package with an identical name to the current
package. This can be overridden with the
--force flag, but in most
cases can simply be addressed by changing the local package name.
There are some very rare and pathological edge-cases where a cycle can cause npm
to try to install a never-ending tree of packages. Here is the simplest case:
A -> B -> A' -> B' -> A -> B -> A' -> B' -> A -> ...
where
A is some version of a package, and
A' is a different
version of the same package. Because
B depends on a different version
of
A than the one that is already in the tree, it must install a
separate copy. The same is true of
A', which must install
B'.
Because
B' depends on the original version of
A, which has been
overridden, the cycle falls into infinite regress.
To avoid this situation, npm flat-out refuses to install any
name@version
that is already present anywhere in the tree of package folder ancestors. A
more correct, but more complex, solution would be to symlink the existing
version into the new location. If this ever affects a real use-case, it will
be investigated.
- •
- npm help 5 folders
- •
- npm help update
- •
- npm help audit
- •
- npm help link
- •
- npm help rebuild
- •
- npm help 7 scripts
- •
- npm help build
- •
- npm help config
- •
- npm help 7 config
- •
- npm help 5 npmrc
- •
- npm help 7 registry
- •
- npm help dist-tag
- •
- npm help uninstall
- •
- npm help shrinkwrap
- •
- npm help 5 package.json