@financial-times/d3-bootloader

Load D3 via SystemJS

Usage no npm install needed!

<script type="module">
  import financialTimesD3Bootloader from 'https://cdn.skypack.dev/@financial-times/d3-bootloader';
</script>

README

@Financial-Times/d3-bootloader

This users SystemJS to bootstrap and load a D3-based project. You can use modern JS because it transpiles everything on-the-fly.

Usage:

  • Create a .html file containing the following code:
  <script src="//unpkg.com/@financial-times/d3-bootloader" async></script>
  • Next, create a file called index.js in the same directory as the above:
import * as d3 from 'd3'; // Import the whole thing...
import {scaleLinear} from 'd3-scale'; // ...Or just bits and pieces, it doesn't matter.

export default async function () {
  return await Promise.resolve('Yep you can use ES2017 here too');
}

Voilà! The above module will run upon page load. Note this only works with D3, and a few of the sundry ft-interactive modules.

  • This also exposes a UMD global named bootD3 that returns a promise containing the resolved index.js module. That means you can then do something like:
<script>
  bootD3.then((index) => {
    index().then(alert);
  });
</script>

...Which, given the above index.js module, will alert with "Yep you can use ES2017 here too".

 What if I need more modules?

It's not like you can include this on page and then add any module in the npmjs.org registry. If you want to add another module (that's deliverable via a CDN like unpkg), add the following before your d3-bootloader script tag:

<script>
  window.D3_BOOTLOADER_MODULES = {
    'd3-jetpack': 'https://unpkg.com/d3-jetpack@2',
  }
</script>

Each key in the map object is what you'll import, and the value is a CDN resource exporting some kind of UMD module.

For more info, please see the SystemJS Configuration API Docs.

Should this be used in production?

Oh hells nawww — on-the-fly Babel transpilation isn't exactly the lightest thing ever.

Not only that, but every module you load from index.js will create a separate request.

This project is mainly intended to help streamline the creation of examples for ft-interactive/visual-vocabulary-templates. Again, you probably don't want to use this in production.