Grouping Libraries
Libraries should be grouped by scope. A library's scope is either application to which it belongs or (for larger applications) a section within that application.
Move Generator
Don't be too anxious about choosing the exact right folder structure from the beginning. Libraries can be moved or renamed using the @nx/workspace:move
generator.
For instance, if a library under the booking
folder is now being shared by multiple apps, you can move it to the shared folder like this:
❯
nx g move --project booking-some-library shared/some-library
For Angular projects, you should use the @nx/angular:move
generator instead.
Remove Generator
Similarly, if you no longer need a library, you can remove it with the @nx/workspace:remove
generator.
❯
nx g remove booking-some-library
Example Workspace
Let's use Nrwl Airlines as an example organization. This organization has two apps, booking
and check-in
. In the Nx workspace, libraries related to booking
are grouped under a libs/booking
folder, libraries related to check-in
are grouped under a libs/check-in
folder and libraries used in both applications are placed in libs/shared
. You can also have nested grouping folders, (i.e. libs/shared/seatmap
).
The purpose of these folders is to help with organizing by scope. We recommend grouping libraries together which are (usually) updated together. It helps minimize the amount of time a developer spends navigating the folder tree to find the right file.
apps/
booking/
check-in/
libs/
booking/ <---- grouping folder
feature-shell/ <---- library
check-in/
feature-shell/
shared/ <---- grouping folder
data-access/ <---- library
seatmap/ <---- grouping folder
data-access/ <---- library
feature-seatmap/ <---- library
Sharing Libraries
One of the main advantages of using a monorepo is that there is more visibility into code that can be reused across many different applications. Shared libraries are a great way to save developers time and effort by reusing a solution to a common problem.
Let’s consider our reference monorepo. The shared-data-access
library contains the code needed to communicate with the back-end (for example, the URL prefix). We know that this would be the same for all libs; therefore, we should place this in the shared lib and properly document it so that all projects can use it instead of writing their own versions.
libs/
booking/
data-access/ <---- app-specific library
shared/
data-access/ <---- shared library
seatmap/
data-access/ <---- shared library
feature-seatmap/ <---- shared library