Add a New Lit Project
The code for this example is available on Github:
Example repository/nrwl/nx-recipes/tree/main/lit
Supported Features
Because we are not using an Nx plugin for Lit, there are few items we'll have to configure manually. We'll have to configure our own build system. There are no pre-created Lit-specific code generators. And we'll have to take care of updating any framework dependencies as needed.
✅ Run Tasks ✅ Cache Task Results ✅ Share Your Cache ✅ Explore the Graph ✅ Distribute Task Execution ✅ Integrate with Editors ✅ Automate Updating Nx ✅ Enforce Module Boundaries 🚫 Use Task Executors 🚫 Use Code Generators 🚫 Automate Updating Framework Dependencies
Install Lit and Other Dependencies
Install all the dependencies we need:
❯
npm i --save-dev @nx/node lit http-server
Create an Application
Directory Flag Behavior ChangesThe command below uses the as-provided directory flag behavior, which is the default in Nx 16.8.0. If you're on an earlier version of Nx or using the derived option, omit the --directory flag. See the workspace layout documentation for more details.
We'll start with a node application and then tweak the settings to match what we need. Add a new node application to your workspace with the following command:
❯
nx g @nx/node:app my-lit-app --directory=apps/my-lit-app
Choose none for the node framework, since we won't be using this as a node app.
Turn the Application into a Lit Application
Update main.ts:
1import { LitElement, html } from 'lit';
2import { customElement, property } from 'lit/decorators.js';
3
4('my-element')
5export class MyElement extends LitElement {
6 ()
7 version = 'STARTING';
8
9 render() {
10 return html`
11 <p>Welcome to the Lit tutorial!</p>
12 <p>This is the ${this.version} code.</p>
13 `;
14 }
15}
16Create index.html:
1
2<html>
3 <head>
4 <script type="module" src="main.js"></script>
5 <style>
6 body {
7 font-family: 'Open Sans', sans-serif;
8 font-size: 1.5em;
9 padding-left: 0.5em;
10 }
11 </style>
12 </head>
13 <body>
14 <my-element></my-element>
15 </body>
16</html>
17Update the Build Task
In the project.json file update the options under the build target. The properties that need to change are format, bundle, thirdParty, and assets:
1{
2 "targets": {
3 "build": {
4 "executor": "@nx/esbuild:esbuild",
5 "outputs": ["{options.outputPath}"],
6 "defaultConfiguration": "production",
7 "options": {
8 "outputPath": "dist/apps/my-lit-app",
9 "format": ["esm"],
10 "bundle": true,
11 "thirdParty": true,
12 "main": "apps/my-lit-app/src/main.ts",
13 "tsConfig": "apps/my-lit-app/tsconfig.app.json",
14 "assets": ["apps/my-lit-app/src/assets", "apps/my-lit-app/index.html"],
15 "generatePackageJson": true,
16 "esbuildOptions": {
17 "sourcemap": true,
18 "outExtension": {
19 ".js": ".js"
20 }
21 }
22 }
23 }
24 }
25}
26Now, when you run the build, there should be index.html, main.js and package.json under dist/apps/my-lit-app. Try it out:
❯
nx build my-lit-app
Update the Serve Task
To serve the app, we'll completely overwrite the existing serve task. Change it to this:
1{
2 "targets": {
3 "serve": {
4 "dependsOn": ["build"],
5 "executor": "nx:run-commands",
6 "options": {
7 "commands": [
8 "http-server dist/apps/my-lit-app",
9 "nx watch --projects=my-lit-app --includeDependentProjects -- nx build my-lit-app"
10 ]
11 }
12 }
13 }
14}
15"dependsOn": ["build"] will ensure that the build task is always run before the serve task. The entries under commands will each be run in parallel. The http-server line serves the build output with a simple server. The nx watch line will automatically re-run the build task any time the application code or any project it depends on changes.
Run the serve task and see your Lit app in action:
❯
nx serve my-lit-app
Create a Library
Directory Flag Behavior ChangesThe command below uses the as-provided directory flag behavior, which is the default in Nx 16.8.0. If you're on an earlier version of Nx or using the derived option, omit the --directory flag. See the workspace layout documentation for more details.
Let's create a library that our Lit application is going to consume. To create a new library, install the @nx/js package and run:
❯
nx g @nx/js:lib my-lib --directory=libs/my-lib
Once the library is created, update the following files.
1export function someFunction(): string {
2 return 'some function';
3}
41import { LitElement, html } from 'lit';
2import { customElement, property } from 'lit/decorators.js';
3import { someFunction } from '@my-org/my-lib';
4
5('my-element')
6export class MyElement extends LitElement {
7 ()
8 version = 'STARTING';
9
10 render() {
11 return html`
12 <p>Welcome to the Lit tutorial!</p>
13 <p>This is the ${this.version} code.</p>
14 <p>Imported from a library: ${someFunction()}.</p>
15 `;
16 }
17}
18Now when you serve your application, you'll see the content from the library being displayed.