eunomia-controller/source/generate/html/html.js

const fs = require(`fs`);
const ejs = require(`ejs`);
const system = require(`./../../variables`)(`./eunomia.json`);

const isMissing = (data, message) => typeof data === 'undefined'

exports.generate = (writeToPath, distToPath, stats, production) => require(`./../../task/index`)(`html`, (resolve, reject) => {
  if (!fs.existsSync(`./eunomia.json`)) {
    reject("eunomia.json required within the root of the project")
  }
  else {
    const eunomia = system;

    if (!eunomia.generate.html.enabled) {
      resolve()
      return false
    }

    try {
      if (!production) {
        // Find the primary chunk used within this project
        const bundle = stats.compilation.chunks.find(x => x.name === `main`).files[0];
        if (bundle == null || typeof bundle === 'undefined' || bundle == ``) {
          return reject(`No main chunk found.`);
        }

        // Get the contents of the html.ejs file to structure the index.html
        const fullPath = `${__dirname}/html.ejs`
        const template = fs.readFileSync(`${fullPath}`, `utf8`);
        if (template == null || typeof template === 'undefined' || template == ``) {
          return reject(`File 'html.ejs' contains no content.`);
        }

        // Generate the rendering function for the html.ejs file
        const render = ejs.compile(template, { filename: `${fullPath}` });
        if (typeof render !== 'function') {
          return reject(`Render contains no function.`);
        }

        // Render the output for the index.html from the html.ejs containing certain variables
        const output = render({ debug: true, bundle: `${distToPath}${bundle}`, config: system.generate.html.app});
        if (output == null || typeof output === 'undefined' || output == ``) {
          return reject(`Rendered output contains no content.`);
        }

        // Write the new index.html to a file in the public folder
        fs.writeFileSync(`${writeToPath}/index.html`, output, `utf8`);
        fs.exists(`${writeToPath}/index.html`, (exists) => {
          if(exists) return resolve();
          else return reject(`'index.html' has not been created`)
        });
      }
      else {
        try {
          fs.exists(`${system.config.webpack}`, (exists) => {
            if (exists) {
              const webpackConfig = require(`../../../../${system.config.webpack}`);
              const fullPath = `${__dirname}/html.ejs`
              const assets = JSON.parse(fs.readFileSync(`${writeToPath}${distToPath}assets.json`, `utf8`));
              const template = fs.readFileSync(`${fullPath}`, `utf8`);
              const render = ejs.compile(template, { filename: `${fullPath}` });
              const output = render({ debug: webpackConfig.debug, bundle: assets.main.js, config: system.generate.html.app, fonts: (typeof system.generate.html.fonts === 'undefined' ? [] : system.generate.html.fonts)});
              fs.writeFileSync(`${writeToPath}/index.html`, output, `utf8`);
              resolve();
            }
            else {
              reject("Webpack config not found. eunomia.json requires a config.webpack path")
            }
          });
        }
        catch (e) {
          console.log(e);
          reject(e);
        }
      }
    }
    catch (e) {
      console.log(e);
      reject("Failed to create a index.html");
    }
  }
});