refactor(example): replaces ESM with CommonJS in helloworld

To understand why check stalniy/casl#331. Also adds note that it's possible to use any package manager to run an example

README.md

@@ -1,6 +1,6 @@
 # CASL Examples
 
-This repository is a monorepo of [CASL](https://github.com/stalniy/casl) examples. Examples illustrate integrations with major frameworks. This repository uses [pnpm](https://pnpm.js.org/) as a package manager.
+This repository is a monorepo of [CASL](https://github.com/stalniy/casl) examples. Examples illustrate integrations with major frameworks. This repository uses [pnpm](https://pnpm.js.org/) to manage all examples as a monorepo but you are not restricted to use pnpm. If you are interested in particular example, just navigate to its folder and use whatever package manager you like.
 
 You can find examples in [packages](./packages) folder. See `README.md` of the specific example for details.
 

packages/hello-world/README.md

@@ -1,14 +1,12 @@
 # CASL hello world
 
-This is a basic example that illustrates the easiest CASL configuration.
+This is a basic example that allows to play around with [CASL](https://stalniy.github.io/casl/v4).
 
-## Requirements
-
-Node version that support experimental modules. Tested on node v12.13
+**Note**: this example uses CommonJS as `@casl/ability` currently doesn't support new `exports` field in package.json and codesandbox doesn't allow to change the version of nodejs (10.x only at the time of writing).
 
 ## Run
 
 ```sh
-pnpm install
-pnpm start
+npm install
+npm start
 ```

packages/hello-world/package.json

@@ -4,7 +4,7 @@
   "description": "CASL helloworld example",
   "main": "index.js",
   "scripts": {
-    "start": "node --experimental-modules src/index.mjs"
+    "start": "node src/index.js"
   },
   "keywords": [
     "casl",

packages/hello-world/src/defineAbility.js

@@ -0,0 +1,6 @@
+const { defineAbility } = require('@casl/ability');
+
+module.exports = defineAbility((can, cannot) => {
+  can('manage', 'all');
+  cannot('delete', 'User');
+});

packages/hello-world/src/index.js

@@ -0,0 +1,7 @@
+const ability = require('./defineAbility');
+
+console.log('can read Post', ability.can('read', 'Post')) // true
+console.log('can read User', ability.can('read', 'User')) // true
+console.log('can update User', ability.can('update', 'User')) // true
+console.log('can delete User', ability.can('delete', 'User')) // false
+console.log('cannot delete User', ability.cannot('delete', 'User')) // true

packages/react-todo/README.md

@@ -8,7 +8,7 @@ This example shows how to integrate [CASL authorization](https://stalniy.github.
 
 ``` bash
 # install dependencies
-pnpm install
+npm install
 
 # serve with hot reload at localhost:3000
 npm start