Calling webpacked code from outside (HTML script tag)

Question

It seems that you want to expose the webpack bundle as a library. You can configure webpack to expose your library in the global context within a variable of your own, like EntryPoint.

I don't know TypeScript so the example uses plain JavaScript instead. But the important piece here is the webpack configuration file, and specifically the output section:

webpack.config.js

module.exports = {
  entry: './index.js',
  output: {
    path: './lib',
    filename: 'yourlib.js',
    libraryTarget: 'var',
    library: 'EntryPoint'
  }
};

index.js

module.exports = {
  run: function () {
    console.log('run from library');
  }
};

Then you will be able to access your library methods like you expect:

<script src="lib/yourlib.js"></script>
<script>
  window.onload = function () {
    EntryPoint.run();
  };
</script>

Check the gist with the actual code.

I managed to get this working without any further webpack.config.js modifications, by simply using the import statement which i called from my main/index.js file:

import EntryPoint from './EntryPoint.js';
window.EntryPoint = EntryPoint;

For reference, here's my weback.config.js file.

Initially I tried accomplishing the same using require, however it assigned the module wrapper to window.EntryPoint as opposed to the actual class.

In my circumstance I was able to call a function from within the bundled JavaScript from another script by writing the function to the window when creating it.

// In the bundled script:
function foo() {
    var modal = document.createElement('div');
}
// Bind to the window
window.foo = foo;
// Then, in the other script where I want to reference the bundled function I just call it as a normal function
<button onClick="window.foo()">Click Me</button>

I wasn't able to use Babel so this worked for me.

I had a similar challenge, I wanted to create a bundle for multiple pages within a journey and wanted each page to have it's own entry point into the code, and without a separate bundle for each page.

Here's my approach, which is very similar to Kurt Williams but from a slightly different angle, also without changing webpack config:

JourneyMaster.js

import { getViewData } from './modules/common';
import { VIEW_DATA_API_URL } from './modules/constants';
import { createLandingPage, createAnotherPage } from './modules/components/pageBuilder';

window.landingPageInit = () => {
    getViewData(VIEW_DATA_API_URL).then(viewData => {
        createLandingPage(viewData);
    });
};

window.anotherPageInit = () => {
    getViewData(VIEW_DATA_API_URL).then(viewData => {
        createAnotherPage(viewData);
    });
};

// I appreciate the above could be one liners,
// but readable at a glance is important to me

Then an example of how I call these methods at the end of the html page:

<script src="/js/JourneyMaster.js"></script>
<script>window.landingPageInit();</script>

WEBPACK.CONFIG.JS

1.USING UMD

module.exports={
            mode:'development',
            entry:'./yourentry.js',
            output:{
                path:path.resolve(__dirname,"dist"),
                filename:'main.js',
                publicPath:'/dist/',
                libraryTarget:'umd', 
                library:'rstate',
                umdNamedDefine: true,
                libraryExport: 'default' 
            }
    }

index.html

<script src="dist/main.js"></script>
<script>
  window.onload = function () {
  rstate()=>{}
</script>

main.js

export default function rstate(){
console.log("i called from html")
}

2.USING VAR

module.exports={
            mode:'development',
            entry:'./yourentry.js',
            output:{
                path:path.resolve(__dirname,"dist"),
                filename:'main.js',
                publicPath:'/dist/',
                libraryTarget:'var', 
                library: 'EntryPoint'
            }
    }

index.html

<script>
  window.onload = function () {
  EntryPoint.rstate()=>{}
</script>

main.js

module.exports={
    rstate=function(){
        console.log("hi module")
    }
}

3.USING AMD as library we use like(for those who want to make lib)

define(['jquery', './aux-lib.js'], function ($) { ..(1).. });