folders - Folder Structures Used by npm Description npm puts various things on your computer. That's its job. This document will tell you what it puts where. tl;dr o Local install (default): puts stuff in ./node_modules of the current package root. o Global install (with -g): puts stuff in /usr/local or wherever node is installed. o Install it locally if you're going to require() it. o Install it globally if you're going to run it on the command line. o If you need both, then install it in both places, or use npm link. prefix Configuration The prefix config defaults to the location where node is installed. On most systems, this is /usr/local. On Windows, it's %AppData%\npm. On Unix systems, it's one level up, since node is typically installed at {prefix}/bin/node rather than {prefix}/node.exe. When the global flag is set, npm installs things into this prefix. When it is not set, it uses the root of the current package, or the current working directory if not in a package already. Node Modules Packages are dropped into the node_modules folder under the prefix. When installing locally, this means that you can require("packagename") to load its main module, or require("packagename/lib/path/to/sub/mod- ule") to load other modules. Global installs on Unix systems go to {prefix}/lib/node_modules. Global installs on Windows go to {prefix}/node_modules (that is, no lib folder.) Scoped packages are installed the same way, except they are grouped together in a sub-folder of the relevant node_modules folder with the name of that scope prefix by the @ symbol, e.g. npm install @myorg/package would place the package in {prefix}/node_mod- ules/@myorg/package. See npm help scope for more details. If you wish to require() a package, then install it locally. Executables When in global mode, executables are linked into {prefix}/bin on Unix, or directly into {prefix} on Windows. Ensure that path is in your ter- minal's PATH environment to run them. When in local mode, executables are linked into ./node_modules/.bin so that they can be made available to scripts run through npm. (For exam- ple, so that a test runner will be in the path when you run npm test.) Man Pages When in global mode, man pages are linked into {prefix}/share/man. When in local mode, man pages are not installed. Man pages are not installed on Windows systems. Cache See npm help cache. Cache files are stored in ~/.npm on Posix, or %AppData%/npm-cache on Windows. This is controlled by the cache configuration param. Temp Files Temporary files are stored by default in the folder specified by the tmp config, which defaults to the TMPDIR, TMP, or TEMP environment variables, or /tmp on Unix and c:\windows\temp on Windows. Temp files are given a unique folder under this root for each run of the program, and are deleted upon successful exit. More Information When installing locally, npm first tries to find an appropriate prefix folder. This is so that npm install foo@1.2.3 will install to the sen- sible root of your package, even if you happen to have cded into some other folder. Starting at the $PWD, npm will walk up the folder tree checking for a folder that contains either a package.json file, or a node_modules folder. If such a thing is found, then that is treated as the effec- tive "current directory" for the purpose of running npm commands. (This behavior is inspired by and similar to git's .git-folder seeking logic when running git commands in a working dir.) If no package root is found, then the current folder is used. When you run npm install foo@1.2.3, then the package is loaded into the cache, and then unpacked into ./node_modules/foo. Then, any of foo's dependencies are similarly unpacked into ./node_modules/foo/node_mod- ules/.... Any bin files are symlinked to ./node_modules/.bin/, so that they may be found by npm scripts when necessary. Global Installation If the global configuration is set to true, then npm will install pack- ages "globally". For global installation, packages are installed roughly the same way, but using the folders described above. Cycles, Conflicts, and Folder Parsimony Cycles are handled using the property of node's module system that it walks up the directories looking for node_modules folders. So, at every stage, if a package is already installed in an ancestor node_mod- ules folder, then it is not installed at the current location. Consider the case above, where foo -> bar -> baz. Imagine if, in addi- tion to that, baz depended on bar, so you'd have: foo -> bar -> baz -> bar -> baz .... However, since the folder structure is: foo/node_mod- ules/bar/node_modules/baz, there's no need to put another copy of bar into .../baz/node_modules, since when it calls require("bar"), it will get the copy that is installed in foo/node_modules/bar. This shortcut is only used if the exact same version would be installed in multiple nested node_modules folders. It is still possible to have a/node_modules/b/node_modules/a if the two "a" packages are different versions. However, without repeating the exact same package multiple times, an infinite regress will always be prevented. Another optimization can be made by installing dependencies at the highest level possible, below the localized "target" folder. Example Consider this dependency graph: foo +-- blerg@1.2.5 +-- bar@1.2.3 | +-- blerg@1.x (latest=1.3.7) | +-- baz@2.x | | `-- quux@3.x | | `-- bar@1.2.3 (cycle) | `-- asdf@* `-- baz@1.2.3 `-- quux@3.x `-- bar In this case, we might expect a folder structure like this: foo +-- node_modules +-- blerg (1.2.5) <---[A] +-- bar (1.2.3) <---[B] | `-- node_modules | +-- baz (2.0.2) <---[C] | | `-- node_modules | | `-- quux (3.2.0) | `-- asdf (2.3.4) `-- baz (1.2.3) <---[D] `-- node_modules `-- quux (3.2.0) <---[E] Since foo depends directly on bar@1.2.3 and baz@1.2.3, those are installed in foo's node_modules folder. Even though the latest copy of blerg is 1.3.7, foo has a specific dependency on version 1.2.5. So, that gets installed at [A]. Since the parent installation of blerg satisfies bar's dependency on blerg@1.x, it does not install another copy under [B]. Bar [B] also has dependencies on baz and asdf, so those are installed in bar's node_modules folder. Because it depends on baz@2.x, it cannot re-use the baz@1.2.3 installed in the parent node_modules folder [D], and must install its own copy [C]. Underneath bar, the baz -> quux -> bar dependency creates a cycle. However, because bar is already in quux's ancestry [B], it does not unpack another copy of bar into that folder. Underneath foo -> baz [D], quux's [E] folder tree is empty, because its dependency on bar is satisfied by the parent folder copy installed at [B]. For a graphical breakdown of what is installed where, use npm ls. Publishing Upon publishing, npm will look in the node_modules folder. If any of the items there are not in the bundledDependencies array, then they will not be included in the package tarball. This allows a package maintainer to install all of their dependencies (and dev dependencies) locally, but only re-publish those items that cannot be found elsewhere. See npm help package.json for more informa- tion. See also o npm help package.json o npm help install o npm help pack o npm help cache o npm help config o npm help npmrc o npm help config o npm help publish
Please see following description for synopsis
FOLDERS(5) FOLDERS(5)
NAME
folders - Folder Structures Used by npm
Description
npm puts various things on your computer. That's its job.
This document will tell you what it puts where.
tl;dr
o Local install (default): puts stuff in ./node_modules of the current
package root.
o Global install (with -g): puts stuff in /usr/local or wherever node
is installed.
o Install it locally if you're going to require() it.
o Install it globally if you're going to run it on the command line.
o If you need both, then install it in both places, or use npm link.
prefix Configuration
The prefix config defaults to the location where node is installed. On
most systems, this is /usr/local. On Windows, it's %AppData%\npm. On
Unix systems, it's one level up, since node is typically installed at
{prefix}/bin/node rather than {prefix}/node.exe.
When the global flag is set, npm installs things into this prefix.
When it is not set, it uses the root of the current package, or the
current working directory if not in a package already.
Node Modules
Packages are dropped into the node_modules folder under the prefix.
When installing locally, this means that you can require("packagename")
to load its main module, or require("packagename/lib/path/to/sub/mod-
ule") to load other modules.
Global installs on Unix systems go to {prefix}/lib/node_modules.
Global installs on Windows go to {prefix}/node_modules (that is, no lib
folder.)
Scoped packages are installed the same way, except they are grouped
together in a sub-folder of the relevant node_modules folder with the
name of that scope prefix by the @ symbol, e.g. npm install
@myorg/package would place the package in {prefix}/node_mod-
ules/@myorg/package. See npm help scope for more details.
If you wish to require() a package, then install it locally.
Executables
When in global mode, executables are linked into {prefix}/bin on Unix,
or directly into {prefix} on Windows. Ensure that path is in your ter-
minal's PATH environment to run them.
When in local mode, executables are linked into ./node_modules/.bin so
that they can be made available to scripts run through npm. (For exam-
ple, so that a test runner will be in the path when you run npm test.)
Man Pages
When in global mode, man pages are linked into {prefix}/share/man.
When in local mode, man pages are not installed.
Man pages are not installed on Windows systems.
Cache
See npm help cache. Cache files are stored in ~/.npm on Posix, or
%AppData%/npm-cache on Windows.
This is controlled by the cache configuration param.
Temp Files
Temporary files are stored by default in the folder specified by the
tmp config, which defaults to the TMPDIR, TMP, or TEMP environment
variables, or /tmp on Unix and c:\windows\temp on Windows.
Temp files are given a unique folder under this root for each run of
the program, and are deleted upon successful exit.
More Information
When installing locally, npm first tries to find an appropriate prefix
folder. This is so that npm install foo@1.2.3 will install to the sen-
sible root of your package, even if you happen to have cded into some
other folder.
Starting at the $PWD, npm will walk up the folder tree checking for a
folder that contains either a package.json file, or a node_modules
folder. If such a thing is found, then that is treated as the effec-
tive "current directory" for the purpose of running npm commands.
(This behavior is inspired by and similar to git's .git-folder seeking
logic when running git commands in a working dir.)
If no package root is found, then the current folder is used.
When you run npm install foo@1.2.3, then the package is loaded into the
cache, and then unpacked into ./node_modules/foo. Then, any of foo's
dependencies are similarly unpacked into ./node_modules/foo/node_mod-
ules/....
Any bin files are symlinked to ./node_modules/.bin/, so that they may
be found by npm scripts when necessary.
Global Installation
If the global configuration is set to true, then npm will install pack-
ages "globally".
For global installation, packages are installed roughly the same way,
but using the folders described above.
Cycles, Conflicts, and Folder Parsimony
Cycles are handled using the property of node's module system that it
walks up the directories looking for node_modules folders. So, at
every stage, if a package is already installed in an ancestor node_mod-
ules folder, then it is not installed at the current location.
Consider the case above, where foo -> bar -> baz. Imagine if, in addi-
tion to that, baz depended on bar, so you'd have: foo -> bar -> baz ->
bar -> baz .... However, since the folder structure is: foo/node_mod-
ules/bar/node_modules/baz, there's no need to put another copy of bar
into .../baz/node_modules, since when it calls require("bar"), it will
get the copy that is installed in foo/node_modules/bar.
This shortcut is only used if the exact same version would be installed
in multiple nested node_modules folders. It is still possible to have
a/node_modules/b/node_modules/a if the two "a" packages are different
versions. However, without repeating the exact same package multiple
times, an infinite regress will always be prevented.
Another optimization can be made by installing dependencies at the
highest level possible, below the localized "target" folder.
Example
Consider this dependency graph:
foo
+-- blerg@1.2.5
+-- bar@1.2.3
| +-- blerg@1.x (latest=1.3.7)
| +-- baz@2.x
| | `-- quux@3.x
| | `-- bar@1.2.3 (cycle)
| `-- asdf@*
`-- baz@1.2.3
`-- quux@3.x
`-- bar
In this case, we might expect a folder structure like this:
foo
+-- node_modules
+-- blerg (1.2.5) <---[A]
+-- bar (1.2.3) <---[B]
| `-- node_modules
| +-- baz (2.0.2) <---[C]
| | `-- node_modules
| | `-- quux (3.2.0)
| `-- asdf (2.3.4)
`-- baz (1.2.3) <---[D]
`-- node_modules
`-- quux (3.2.0) <---[E]
Since foo depends directly on bar@1.2.3 and baz@1.2.3, those are
installed in foo's node_modules folder.
Even though the latest copy of blerg is 1.3.7, foo has a specific
dependency on version 1.2.5. So, that gets installed at [A]. Since
the parent installation of blerg satisfies bar's dependency on
blerg@1.x, it does not install another copy under [B].
Bar [B] also has dependencies on baz and asdf, so those are installed
in bar's node_modules folder. Because it depends on baz@2.x, it cannot
re-use the baz@1.2.3 installed in the parent node_modules folder [D],
and must install its own copy [C].
Underneath bar, the baz -> quux -> bar dependency creates a cycle.
However, because bar is already in quux's ancestry [B], it does not
unpack another copy of bar into that folder.
Underneath foo -> baz [D], quux's [E] folder tree is empty, because its
dependency on bar is satisfied by the parent folder copy installed at
[B].
For a graphical breakdown of what is installed where, use npm ls.
Publishing
Upon publishing, npm will look in the node_modules folder. If any of
the items there are not in the bundledDependencies array, then they
will not be included in the package tarball.
This allows a package maintainer to install all of their dependencies
(and dev dependencies) locally, but only re-publish those items that
cannot be found elsewhere. See npm help package.json for more informa-
tion.
See also
o npm help package.json
o npm help install
o npm help pack
o npm help cache
o npm help config
o npm help npmrc
o npm help config
o npm help publish
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+--------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+--------------------------+
|Availability | runtime/nodejs/nodejs-18 |
+---------------+--------------------------+
|Stability | Pass-thru volatile |
+---------------+--------------------------+
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://github.com/nodejs/node/ar-
chive/v18.1.0.zip.
Further information about this software can be found on the open source
community website at https://github.com/nodejs/node.
April 2022 FOLDERS(5)