How to get image that is within a data attrbute with Webpack 2?

Question

I am using .pug templates for my HTML and standard src attributes on my images like so:

img(src=`../images/${image}`)

When I run webpack -p, any images defined in the src's of my images are found by Webpack and placed into my dist directory. This is exactly what I would expect to happen.

However, I now have a requirement to lazy load my images, so I want to place the reference to the image into a data-src attribute instead of the standard src, like so:

img(data-src=`../images/${image}` src='data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7')

Running webpack -p again when I do this though, does not grab the images.

Is there any way that I can make Webpack look at non-src attributes to realise that it requires those images as part of the production build?

Answer 1

Okay. It turns out that html-loader has an option to pass in tag / attribute types for the loader to parse through, called attrs, which is an array of these configurations.

I achieved this doing it like so:

{
  test: /\.pug$/,
  use: [
    {
      loader: 'html-loader',
      options: {
        attrs: ['img:src', 'img:data-src', 'link:href']
      }
    },
    {
      loader: 'pug-html-loader',
      options: {
        pretty: true,
        exports: false
      }
    }
  ]
}

Now running webpack -p appears to get those images.

Hope that this helps someone out sometime.

Answer 2

options can still bug with html-loader. You might need to use this instead https://webpack.js.org/plugins/loader-options-plugin/