Chained Preprocessors

Chained Preprocessors brings the ease of using different preprocessors together. You can use as many preprocessors as you want, although you have to preinstall them via npm. Just add them to package file. In order to use preprocessors you have to chain extensions of file, in order reverse to preprocessing. I.e. for file.html.md.hbs first will be used handlebars preprocessor, and then markdown.

Installation

npm install --save chained-preprocessors

Install preprocessors you want to use, i.e.:

npm install --save coffee-script node-sass handlebars commonmark ejs

Usage

  var chainedPreprocessors = require('chained-preprocessors');
  var options = {
    all: {
      user: 'Bill Murray'
    }
  };

  chainedPreprocessors
    .renderFile('./pages/index.md.hbs', options, function (err, html){
      console.log(html);
    });

  // Or pass contents of file, and file extensions ordered by related
  // preprocessor to be used i.e. for same file:

    chainedPreprocessors
    .render(fileContents, ['hbs', 'md'], options, function (err, html) {
      console.log(html);
    });

You can specify preprocessor specific options via its key, like this:

  var options = {
    all: {
      user: 'Bill Murray',
    },
    hbs: {
      user: 'Tom Hanks,
      noEscape: true
    }
  };

Options

You can normalize helpers - pass context as this to helper functions, as well not passing template specific arguments. For that you can use normalizeHelpers options along with helpers object of functions. Template specific arguments then can be accessed via this.arguments.

{
  normalizeHelpers: true,
  helpers: {
    fullName: (firstName) => {
       firstName + this.lastName;
    }
  }
}

Examples

So let's say you want to pass some variables to you sass stylesheets, no problem:

/* styles.css.scss.ejs */

$primary-color: <%= primaryColor %>

.header {
  background: $primary-color;
  <% if (environment === 'development') { %>
    font-weight: bold;
  <% } %>
}

  var options = {
    all: {
      primaryColor: 'red',
      environment: 'development'
    }
  };

  chainedPreprocessors
    .renderFile('styles.css.scss.ejs', options, function (err, html) {
    console.log(html);
  });

Will result in:

.header {
  background: red;
  font-weight: bold;
}