Using Nx Libraries with Firebase Functions

Nx-Firebase supports use of Nx Libraries within functions code.

Creating a library

To use a shared library with an Nx Firebase Function Application, simply create a Typescript Nx node library in your workspace:

nx g @nx/js:lib mylib --importPath="@myorg/mylib [--bundler=<bundler>]

Note: The --importPath option is highly recommended to ensure the correct typescript aliases and npm package configurations for your library.

You can now:

import { stuff } from '@myorg/mynodelib'

in your Firebase functions code as you'd normally expect.

You can then build your Firebase application or function with:

nx build <firebase-app-name>

OR

nx build <firebase-function-name>

Firebase functions use esbuild to bundle function code, we gain a few benefits:

Nx takes care of ensuring all necessary dependencies will be also built.
It does not matter if libraries are buildable or non-buildable, as esbuild builds from Typescript sources, however buildable libraries may be preferred since esbuild does not do type checking of imported libraries.
We do not have to worry about how we structure libraries anymore for optimal function runtime.
For instance, we can use barrel imports freely, since esbuild will treeshake unused code and inline imports into the bundled output main.js
We can create as many libraries as we wish for our functions to use, and organise them in whatever makes most sense for the workspace
For cleaner code sharing, Firebase function applications can simply import a library module containing the firebase function export/implementation