workspaces(7) workspaces(7)
NAME
workspaces - Working with workspaces
Description
Workspaces is a generic term that refers to the set of features in the
npm cli that provides support for managing multiple packages from your
local file system from within a singular top-level, root package.
This set of features makes up for a much more streamlined workflow
handling linked packages from the local file system. It automates the
linking process as part of npm install and removes the need to manually
use npm link in order to add references to packages that should be
symlinked into the current node_modules folder.
We also refer to these packages being auto-symlinked during npm install
as a single workspace, meaning it's a nested package within the current
local file system that is explicitly defined in the package.json
</configuring-npm/package-json#workspaces> workspaces configuration.
Defining workspaces
Workspaces are usually defined via the workspaces property of the
package.json </configuring-npm/package-json#workspaces> file, e.g:
{
"name": "my-workspaces-powered-project",
"workspaces": [
"packages/a"
]
}
Given the above package.json example living at a current working
directory . that contains a folder named packages/a that itself
contains a package.json inside it, defining a Node.js package, e.g:
+-- package.json
`-- packages
+-- a
| `-- package.json
The expected result once running npm install in this current working
directory . is that the folder packages/a will get symlinked to the
node_modules folder of the current working dir.
Below is a post npm install example, given that same previous example
structure of files and folders:
+-- node_modules
| `-- a -> ../packages/a
+-- package-lock.json
+-- package.json
`-- packages
+-- a
| `-- package.json
Getting started with workspaces
You may automate the required steps to define a new workspace using npm
help init. For example in a project that already has a package.json
defined you can run:
npm init -w ./packages/a
This command will create the missing folders and a new package.json
file (if needed) while also making sure to properly configure the
"workspaces" property of your root project package.json.
Adding dependencies to a workspace
It's possible to directly add/remove/update dependencies of your
workspaces using the workspace config </using-npm/config#workspace>.
For example, assuming the following structure:
+-- package.json
`-- packages
+-- a
| `-- package.json
`-- b
`-- package.json
If you want to add a dependency named abbrev from the registry as a
dependency of your workspace a, you may use the workspace config to
tell the npm installer that package should be added as a dependency of
the provided workspace:
npm install abbrev -w a
Note: other installing commands such as uninstall, ci, etc will also
respect the provided workspace configuration.
Using workspaces
Given the specifics of how Node.js handles module resolution
<https://nodejs.org/dist/latest-
v14.x/docs/api/modules.html#modules_all_together> it's possible to
consume any defined workspace by its declared package.json name.
Continuing from the example defined above, let's also create a Node.js
script that will require the workspace a example module, e.g:
// ./packages/a/index.js
module.exports = 'a'
// ./lib/index.js
const moduleA = require('a')
console.log(moduleA) // -> a
When running it with:
node lib/index.js
This demonstrates how the nature of node_modules resolution allows for
workspaces to enable a portable workflow for requiring each workspace
in such a way that is also easy to npm help publish these nested
workspaces to be consumed elsewhere.
Running commands in the context of workspaces
You can use the workspace configuration option to run commands in the
context of a configured workspace. Additionally, if your current
directory is in a workspace, the workspace configuration is implicitly
set, and prefix is set to the root workspace.
Following is a quick example on how to use the npm run command in the
context of nested workspaces. For a project containing multiple
workspaces, e.g:
+-- package.json
`-- packages
+-- a
| `-- package.json
`-- b
`-- package.json
By running a command using the workspace option, it's possible to run
the given command in the context of that specific workspace. e.g:
npm run test --workspace=a
You could also run the command within the workspace.
cd packages/a && npm run test
Either will run the test script defined within the
./packages/a/package.json file.
Please note that you can also specify this argument multiple times in
the command-line in order to target multiple workspaces, e.g:
npm run test --workspace=a --workspace=b
Or run the command for each workspace within the 'packages' folder:
npm run test --workspace=packages
It's also possible to use the workspaces (plural) configuration option
to enable the same behavior but running that command in the context of
all configured workspaces. e.g:
npm run test --workspaces
Will run the test script in both ./packages/a and ./packages/b.
Commands will be run in each workspace in the order they appear in your
package.json
{
"workspaces": [ "packages/a", "packages/b" ]
}
Order of run is different with:
{
"workspaces": [ "packages/b", "packages/a" ]
}
Ignoring missing scripts
It is not required for all of the workspaces to implement scripts run
with the npm run command.
By running the command with the --if-present flag, npm will ignore
workspaces missing target script.
npm run test --workspaces --if-present
See also
o npm help install
o npm help publish
o npm help run-script
o npm help config
February 2024 workspaces(7)
npm 10.5.0 - Generated Thu Feb 29 07:27:52 CST 2024