@mapbox/batfish/dist/node/inline-css-worker.js

The React-powered static-site generator you didn't know you wanted

//      
'use strict';

const fs = require('fs');
const pify = require('pify');
const postcss = require('postcss');
const postcssCsso = require('postcss-csso');
const postcssHtmlFilter = require('@mapbox/postcss-html-filter');
const constants = require('./constants');
const rethrowPostcssError = require('./rethrow-postcss-error');

// A worker script invoked by inline-css.js
function inlineCssWorker(
  htmlPath        ,
  cssPath        ,
  callback                          
) {
  Promise.all([
    pify(fs.readFile)(cssPath, 'utf8'),
    pify(fs.readFile)(htmlPath, 'utf8')
  ])
    .then((data) => {
      const css = data[0];
      const html = data[1];
      return postcss()
        .use(postcssHtmlFilter({ html }))
        .use(postcssCsso())
        .process(css, { from: cssPath, to: cssPath })
        .catch(rethrowPostcssError)
        .then((result                 ) => {
          return html.replace(
            constants.INLINE_CSS_MARKER,
            `<style>${result.css}</style>`
          );
        });
    })
    .then((htmlWithCss) => pify(fs.writeFile)(htmlPath, htmlWithCss))
    .then(
      () => {
        callback();
      },
      (error) => {
        callback(error);
      }
    );
}

module.exports = inlineCssWorker;