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 package-lock.json(5) and npm-shrinkwrap(1).
A package
is:
package.json(5)
file<name>@<version>
that is published on the registry (see npm-registry(7)
) with (c)<name>@<tag>
(see npm-dist-tag(1)
) that points to (d)<name>
that has a "latest" tag satisfying (e)<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 package.json(5)
.
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:
.tar
, .tar.gz
, or .tgz
as
the extension.package/
). npm strips one directory layer when installing the package (an equivalent of tar x --strip-components=1
is run).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-config(7)
. 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 sax
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-scope(7)
.
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 package.json(5)
.
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.
npm install sax --force
The -g
or --global
argument will cause npm to install the package globally
rather than locally. See npm-folders(5)
.
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-scripts(7)
.
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-audit(1)
for details on what is sent.
See npm-config(7)
. 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:
A
+-- B
+-- C
+-- D
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-folders(5) 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.