Developing a Node CLI App in an NX monorepo

Bare bones setup. Using NX version 17.

Create the app

npx nx g @nx/node:app --name cli --directory packages/cli --framework none --e2eTestRunner none --unitTestRunner none

Install Commander

npm i -S commander @commander-js/extra-typings

Configure targets

Modify the default build target's development configuration to include "watch": true.

{
  "name": "cli",
  "$schema": "../../node_modules/nx/schemas/project-schema.json",
  "sourceRoot": "packages/cli/src",
  "projectType": "application",
  "targets": {
    "build": {
      "executor": "@nx/esbuild:esbuild",
      "outputs": ["{options.outputPath}"],
      "defaultConfiguration": "production",
      "options": {
        "platform": "node",
        "outputPath": "dist/packages/cli",
        "format": ["cjs"],
        "bundle": false,
        "main": "packages/cli/src/main.ts",
        "tsConfig": "packages/cli/tsconfig.app.json",
        "assets": ["packages/cli/src/assets"],
        "generatePackageJson": true,
        "esbuildOptions": {
          "sourcemap": true,
          "outExtension": {
            ".js": ".js"
          }
        }
      },
      "configurations": {
        "development": {
          "watch": true
        },
        "production": {
          "esbuildOptions": {
            "sourcemap": false,
            "outExtension": {
              ".js": ".js"
            }
          }
        }
      }
    },
    "lint": {
      "executor": "@nx/eslint:lint",
      "outputs": ["{options.outputFile}"]
    }
  },
  "tags": []
}

Write a program

// packages/cli/src/main.ts
import { program } from "@commander-js/extra-typings";

program.command("list").action(async () => {
  const things = ["one", "two", "three"];
  things.forEach((thing) => console.log(thing));
});

program.parse();

Start the development server

npx nx run cli:build:development

This will watch for changes and recompile.

Run the program

node dist/packages/cli/main.js list

Output:

one
two
three

Grow your CLI App from here

Visit the Commander.js reference.

Comments

[Fyodor]

That's all good but I'm genuinely curious: why would anyone do that? (I mean increasing setup complexity for a CLI project)