npm-exec - Run a command from a local or remote npm package Synopsis npm exec -- <pkg>[@<version>] [args...] npm exec --package=<pkg>[@<version>] -- <cmd> [args...] npm exec -c '<cmd> [args...]' npm exec --package=foo -c '<cmd> [args...]' alias: x Description This command allows you to run an arbitrary command from an npm package (either one installed locally, or fetched remotely), in a similar con- text as running it via npm run. Run without positional arguments or --call, this allows you to interac- tively run commands in the same sort of shell environment that pack- age.json scripts are run. Interactive mode is not supported in CI environments when standard input is a TTY, to prevent hangs. Whatever packages are specified by the --package option will be pro- vided in the PATH of the executed command, along with any locally installed package executables. The --package option may be specified multiple times, to execute the supplied command in an environment where all specified packages are available. If any requested packages are not present in the local project depen- dencies, then they are installed to a folder in the npm cache, which is added to the PATH environment variable in the executed process. A prompt is printed (which can be suppressed by providing either --yes or --no). Package names provided without a specifier will be matched with what- ever version exists in the local project. Package names with a speci- fier will only be considered a match if they have the exact same name and version as the local dependency. If no -c or --call option is provided, then the positional arguments are used to generate the command string. If no --package options are provided, then npm will attempt to determine the executable name from the package specifier provided as the first positional argument accord- ing to the following heuristic: o If the package has a single entry in its bin field in package.json, or if all entries are aliases of the same command, then that command will be used. o If the package has multiple bin entries, and one of them matches the unscoped portion of the name field, then that command will be used. o If this does not result in exactly one option (either because there are no bin entries, or none of them match the name of the package), then npm exec exits with an error. To run a binary other than the named binary, specify one or more --package options, which will prevent npm from inferring the package from the first command argument. npx vs npm exec When run via the npx binary, all flags and options must be set prior to any positional arguments. When run via npm exec, a double-hyphen -- flag can be used to suppress npm's parsing of switches and options that should be sent to the executed command. For example: $ npx foo@latest bar --package=@npmcli/foo In this case, npm will resolve the foo package name, and run the fol- lowing command: $ foo bar --package=@npmcli/foo Since the --package option comes after the positional arguments, it is treated as an argument to the executed command. In contrast, due to npm's argument parsing logic, running this command is different: $ npm exec foo@latest bar --package=@npmcli/foo In this case, npm will parse the --package option first, resolving the @npmcli/foo package. Then, it will execute the following command in that context: $ foo@latest bar The double-hyphen character is recommended to explicitly tell npm to stop parsing command line options and switches. The following command would thus be equivalent to the npx command above: $ npm exec -- foo@latest bar --package=@npmcli/foo Configuration package o Default: o Type: String (can be set multiple times) The package to install for npm help exec call o Default: "" o Type: String Optional companion option for npm exec, npx that allows for specifying a custom command to be run along with the installed packages. npm exec --package yo --package generator-node --call "yo node" workspace o Default: o Type: String (can be set multiple times) Enable running a command in the context of the configured workspaces of the current project while filtering by running only the workspaces defined by this configuration option. Valid values for the workspace config are either: o Workspace names o Path to a workspace directory o Path to a parent workspace directory (will result in selecting all workspaces within that folder) When set for the npm init command, this may be set to the folder of a workspace which does not yet exist, to create the folder and set it up as a brand new workspace within the project. This value is not exported to the environment for child processes. workspaces o Default: null o Type: null or Boolean Set to true to run the command in the context of all configured workspaces. Explicitly setting this to false will cause commands like install to ignore workspaces altogether. When not set explicitly: o Commands that operate on the node_modules tree (install, update, etc.) will link workspaces into the node_modules folder. - Commands that do other things (test, exec, publish, etc.) will operate on the root project, unless one or more workspaces are specified in the workspace config. This value is not exported to the environment for child processes. include-workspace-root o Default: false o Type: Boolean Include the workspace root when workspaces are enabled for a command. When false, specifying individual workspaces via the workspace config, or all workspaces via the workspaces flag, will cause npm to operate only on the specified workspaces, and not on the root project. This value is not exported to the environment for child processes. Examples Run the version of tap in the local dependencies, with the provided arguments: $ npm exec -- tap --bail test/foo.js $ npx tap --bail test/foo.js Run a command other than the command whose name matches the package name by specifying a --package option: $ npm exec --package=foo -- bar --bar-argument # ~ or ~ $ npx --package=foo bar --bar-argument Run an arbitrary shell script, in the context of the current project: $ npm x -c 'eslint && say "hooray, lint passed"' $ npx -c 'eslint && say "hooray, lint passed"' Workspaces support You may use the workspace or workspaces configs in order to run an arbitrary command from an npm package (either one installed locally, or fetched remotely) in the context of the specified workspaces. If no positional argument or --call option is provided, it will open an interactive subshell in the context of each of these configured workspaces one at a time. Given a project with configured workspaces, e.g: . +-- package.json `-- packages +-- a | `-- package.json +-- b | `-- package.json `-- c `-- package.json Assuming the workspace configuration is properly set up at the root level package.json file. e.g: { "workspaces": [ "./packages/*" ] } You can execute an arbitrary command from a package in the context of each of the configured workspaces when using the workspaces configura- tion options, in this example we're using eslint to lint any js file found within each workspace folder: npm exec --ws -- eslint ./*.js Filtering workspaces It's also possible to execute a command in a single workspace using the workspace config along with a name or directory path: npm exec --workspace=a -- eslint ./*.js The workspace config can also be specified multiple times in order to run a specific script in the context of multiple workspaces. When defining values for the workspace config in the command line, it also possible to use -w as a shorthand, e.g: npm exec -w a -w b -- eslint ./*.js This last command will run the eslint command in both ./packages/a and ./packages/b folders. Compatibility with Older npx Versions The npx binary was rewritten in npm v7.0.0, and the standalone npx package deprecated at that time. npx uses the npm exec command instead of a separate argument parser and install process, with some affor- dances to maintain backwards compatibility with the arguments it accepted in previous versions. This resulted in some shifts in its functionality: o Any npm config value may be provided. o To prevent security and user-experience problems from mistyping pack- age names, npx prompts before installing anything. Suppress this prompt with the -y or --yes option. o The --no-install option is deprecated, and will be converted to --no. o Shell fallback functionality is removed, as it is not advisable. o The -p argument is a shorthand for --parseable in npm, but shorthand for --package in npx. This is maintained, but only for the npx exe- cutable. o The --ignore-existing option is removed. Locally installed bins are always present in the executed process PATH. o The --npm option is removed. npx will always use the npm it ships with. o The --node-arg and -n options are removed. o The --always-spawn option is redundant, and thus removed. o The --shell option is replaced with --script-shell, but maintained in the npx executable for backwards compatibility. A note on caching The npm cli utilizes its internal package cache when using the package name specified. You can use the following to change how and when the cli uses this cache. See npm help cache for more on how the cache works. prefer-online Forces staleness checks for packages, making the cli look for updates immediately even if the package is already in the cache. prefer-offline Bypasses staleness checks for packages. Missing data will still be requested from the server. To force full offline mode, use offline. offline Forces full offline mode. Any packages not locally cached will result in an error. workspace o Default: o Type: String (can be set multiple times) Enable running a command in the context of the configured workspaces of the current project while filtering by running only the workspaces defined by this configuration option. Valid values for the workspace config are either: o Workspace names o Path to a workspace directory o Path to a parent workspace directory (will result to selecting all of the nested workspaces) This value is not exported to the environment for child processes. workspaces o Alias: --ws o Type: Boolean o Default: false Run scripts in the context of all configured workspaces for the current project. See Also o npm help run-script o npm help scripts o npm help test o npm help start o npm help restart o npm help stop o npm help config o npm help workspaces o npm help npx
Please see following description for synopsis
NPM-EXEC(1) NPM-EXEC(1)
NAME
npm-exec - Run a command from a local or remote npm package
Synopsis
npm exec -- <pkg>[@<version>] [args...]
npm exec --package=<pkg>[@<version>] -- <cmd> [args...]
npm exec -c '<cmd> [args...]'
npm exec --package=foo -c '<cmd> [args...]'
alias: x
Description
This command allows you to run an arbitrary command from an npm package
(either one installed locally, or fetched remotely), in a similar con-
text as running it via npm run.
Run without positional arguments or --call, this allows you to interac-
tively run commands in the same sort of shell environment that pack-
age.json scripts are run. Interactive mode is not supported in CI
environments when standard input is a TTY, to prevent hangs.
Whatever packages are specified by the --package option will be pro-
vided in the PATH of the executed command, along with any locally
installed package executables. The --package option may be specified
multiple times, to execute the supplied command in an environment where
all specified packages are available.
If any requested packages are not present in the local project depen-
dencies, then they are installed to a folder in the npm cache, which is
added to the PATH environment variable in the executed process. A
prompt is printed (which can be suppressed by providing either --yes or
--no).
Package names provided without a specifier will be matched with what-
ever version exists in the local project. Package names with a speci-
fier will only be considered a match if they have the exact same name
and version as the local dependency.
If no -c or --call option is provided, then the positional arguments
are used to generate the command string. If no --package options are
provided, then npm will attempt to determine the executable name from
the package specifier provided as the first positional argument accord-
ing to the following heuristic:
o If the package has a single entry in its bin field in package.json,
or if all entries are aliases of the same command, then that command
will be used.
o If the package has multiple bin entries, and one of them matches the
unscoped portion of the name field, then that command will be used.
o If this does not result in exactly one option (either because there
are no bin entries, or none of them match the name of the package),
then npm exec exits with an error.
To run a binary other than the named binary, specify one or more
--package options, which will prevent npm from inferring the package
from the first command argument.
npx vs npm exec
When run via the npx binary, all flags and options must be set prior to
any positional arguments. When run via npm exec, a double-hyphen --
flag can be used to suppress npm's parsing of switches and options that
should be sent to the executed command.
For example:
$ npx foo@latest bar --package=@npmcli/foo
In this case, npm will resolve the foo package name, and run the fol-
lowing command:
$ foo bar --package=@npmcli/foo
Since the --package option comes after the positional arguments, it is
treated as an argument to the executed command.
In contrast, due to npm's argument parsing logic, running this command
is different:
$ npm exec foo@latest bar --package=@npmcli/foo
In this case, npm will parse the --package option first, resolving the
@npmcli/foo package. Then, it will execute the following command in
that context:
$ foo@latest bar
The double-hyphen character is recommended to explicitly tell npm to
stop parsing command line options and switches. The following command
would thus be equivalent to the npx command above:
$ npm exec -- foo@latest bar --package=@npmcli/foo
Configuration
package
o Default:
o Type: String (can be set multiple times)
The package to install for npm help exec
call
o Default: ""
o Type: String
Optional companion option for npm exec, npx that allows for specifying
a custom command to be run along with the installed packages.
npm exec --package yo --package generator-node --call "yo node"
workspace
o Default:
o Type: String (can be set multiple times)
Enable running a command in the context of the configured workspaces of
the current project while filtering by running only the workspaces
defined by this configuration option.
Valid values for the workspace config are either:
o Workspace names
o Path to a workspace directory
o Path to a parent workspace directory (will result in selecting all
workspaces within that folder)
When set for the npm init command, this may be set to the folder of a
workspace which does not yet exist, to create the folder and set it up
as a brand new workspace within the project.
This value is not exported to the environment for child processes.
workspaces
o Default: null
o Type: null or Boolean
Set to true to run the command in the context of all configured
workspaces.
Explicitly setting this to false will cause commands like install to
ignore workspaces altogether. When not set explicitly:
o Commands that operate on the node_modules tree (install, update,
etc.) will link workspaces into the node_modules folder. - Commands
that do other things (test, exec, publish, etc.) will operate on the
root project, unless one or more workspaces are specified in the
workspace config.
This value is not exported to the environment for child processes.
include-workspace-root
o Default: false
o Type: Boolean
Include the workspace root when workspaces are enabled for a command.
When false, specifying individual workspaces via the workspace config,
or all workspaces via the workspaces flag, will cause npm to operate
only on the specified workspaces, and not on the root project.
This value is not exported to the environment for child processes.
Examples
Run the version of tap in the local dependencies, with the provided
arguments:
$ npm exec -- tap --bail test/foo.js
$ npx tap --bail test/foo.js
Run a command other than the command whose name matches the package
name by specifying a --package option:
$ npm exec --package=foo -- bar --bar-argument
# ~ or ~
$ npx --package=foo bar --bar-argument
Run an arbitrary shell script, in the context of the current project:
$ npm x -c 'eslint && say "hooray, lint passed"'
$ npx -c 'eslint && say "hooray, lint passed"'
Workspaces support
You may use the workspace or workspaces configs in order to run an
arbitrary command from an npm package (either one installed locally, or
fetched remotely) in the context of the specified workspaces. If no
positional argument or --call option is provided, it will open an
interactive subshell in the context of each of these configured
workspaces one at a time.
Given a project with configured workspaces, e.g:
.
+-- package.json
`-- packages
+-- a
| `-- package.json
+-- b
| `-- package.json
`-- c
`-- package.json
Assuming the workspace configuration is properly set up at the root
level package.json file. e.g:
{
"workspaces": [ "./packages/*" ]
}
You can execute an arbitrary command from a package in the context of
each of the configured workspaces when using the workspaces configura-
tion options, in this example we're using eslint to lint any js file
found within each workspace folder:
npm exec --ws -- eslint ./*.js
Filtering workspaces
It's also possible to execute a command in a single workspace using the
workspace config along with a name or directory path:
npm exec --workspace=a -- eslint ./*.js
The workspace config can also be specified multiple times in order to
run a specific script in the context of multiple workspaces. When
defining values for the workspace config in the command line, it also
possible to use -w as a shorthand, e.g:
npm exec -w a -w b -- eslint ./*.js
This last command will run the eslint command in both ./packages/a and
./packages/b folders.
Compatibility with Older npx Versions
The npx binary was rewritten in npm v7.0.0, and the standalone npx
package deprecated at that time. npx uses the npm exec command instead
of a separate argument parser and install process, with some affor-
dances to maintain backwards compatibility with the arguments it
accepted in previous versions.
This resulted in some shifts in its functionality:
o Any npm config value may be provided.
o To prevent security and user-experience problems from mistyping pack-
age names, npx prompts before installing anything. Suppress this
prompt with the -y or --yes option.
o The --no-install option is deprecated, and will be converted to --no.
o Shell fallback functionality is removed, as it is not advisable.
o The -p argument is a shorthand for --parseable in npm, but shorthand
for --package in npx. This is maintained, but only for the npx exe-
cutable.
o The --ignore-existing option is removed. Locally installed bins are
always present in the executed process PATH.
o The --npm option is removed. npx will always use the npm it ships
with.
o The --node-arg and -n options are removed.
o The --always-spawn option is redundant, and thus removed.
o The --shell option is replaced with --script-shell, but maintained in
the npx executable for backwards compatibility.
A note on caching
The npm cli utilizes its internal package cache when using the package
name specified. You can use the following to change how and when the
cli uses this cache. See npm help cache for more on how the cache
works.
prefer-online
Forces staleness checks for packages, making the cli look for updates
immediately even if the package is already in the cache.
prefer-offline
Bypasses staleness checks for packages. Missing data will still be
requested from the server. To force full offline mode, use offline.
offline
Forces full offline mode. Any packages not locally cached will result
in an error.
workspace
o Default:
o Type: String (can be set multiple times)
Enable running a command in the context of the configured workspaces of
the current project while filtering by running only the workspaces
defined by this configuration option.
Valid values for the workspace config are either:
o Workspace names
o Path to a workspace directory
o Path to a parent workspace directory (will result to selecting all of
the nested workspaces)
This value is not exported to the environment for child processes.
workspaces
o Alias: --ws
o Type: Boolean
o Default: false
Run scripts in the context of all configured workspaces for the current
project.
See Also
o npm help run-script
o npm help scripts
o npm help test
o npm help start
o npm help restart
o npm help stop
o npm help config
o npm help workspaces
o npm help npx
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 NPM-EXEC(1)