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javascriptwebpacknunjuckshtml-webpack-plugin

Using nunjucks with htmlWebpackPlugin using dynamic vars in the template

I'm searching a way of using Nunjucks with the htmlWebpackPlugin to generate some html files on webpack compiling.

What I achieved so far

I managed to actually generate HTML from nunjucks template files through the nunjucks-html-loader but looking a bit closer to the code of said loader, the render method is called without sending vars to the templates.

So, for now with the following plugin config, I generate HTML without dynamically inserted vars

new HtmlWebpackPlugin({
  filename: path.join(__dirname, '/' + page.filename),
  template: 'nunjucks-html-loader!assets/templates/' + page.name + '.njk'
})

What I tried

For a testing purpose, I tried some changes on the node_module itself (I know, I know...) and changed

html = template.render(nunjucksContext);

into

html = template.render(nunjucksContext, { globals: global.globals });

Trying to define global.globals in my webpack.config.js file but this crashes with the following error

ERROR in Error: Child compilation failed: Module build failed: TypeError: parentFrame.push is not a function

which is beyond my comprehension.

What I want

Is to use an extendable template engine like nunjucks which allows me to structure my templates like the following

<html>
<!-- layout structure inherited from every template -->
</html>

Every page I make extends the layout and only overrides some blocks

What I try to avoid

Partials like for exemple

header file :

<html>
<!-- header layout -->

footer file

<!-- footer layout -->
</html>

Every page I make includes partials

So my question is : Is it even possible tu use a template engine supporting inheritance like nunjucks with the htmlWebpackPlugin or is it mandatory to use another one like ejs for exemple and chunking the layout into partials which I do not like?

Solution

  • Alright, so I found a workaround here with the nunjucks-isomorphic-loader which seems not super supported but still. It works for now !

    Here's my webPack config

    const path = require('path')
const webpack = require('webpack')
const HtmlWebpackPlugin = require('html-webpack-plugin')

const DEV_ENV = process.env.NODE_ENV === 'dev'

const wpConfig = {
  entry: './assets/js/app.js',

  output: {
    path: path.resolve('./dist/js'),
    filename: 'bundle.js'
  },

  module: {
    rules: [
      // Javascript
      {
        test: /\.js$/,
        exclude: /(node_modules)/,
        use: {
          loader: 'babel-loader'
        }
      },

      // Nunjucks - HTML
      {
        test: /\.njk$/,
        use: [
          {
            loader: 'nunjucks-isomorphic-loader',
            query: {
              root: [path.resolve(__dirname, 'assets/templates')]
            }
          }
        ]
      }
    ]
  },

  plugins: [
    new webpack.DefinePlugin({
      DEV_ENV: DEV_ENV
    }),

    new HtmlWebpackPlugin({
      myOptions: { foo: 'bar' },
      filename: path.join(__dirname, '/' + page.filename),
      template: 'assets/templates/index.njk'
    })
  ]
}

module.exports = wpConfig

    having the following templates

    _layout.njk

    {% set vars = htmlWebpackPlugin.options.myOptions %}

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>{{ vars.foo }}</title>
  </head>
  <body>
    <header>
    {% block header %}
      <h1 class="header-logo">
        <a href="#">{{ vars.foo }}</a><!-- Outputs bar -->
      </h1>
    {% endblock %}
    </header>

    {% block content %}

    {% endblock %}
  </body>
</html>

    index.njk

    {% extends "_layout.njk" %}

{% block content %}
here's the content of my `foo` var: {{ vars.foo }}
{% endblock %}