build.js

const path = require("path");
const sharp = require("sharp");
const glob = require("glob");
const fs = require('fs');

/**
 * Images
 */
const inputDir = "assets/img/";
const outputDir = "public/img/";
var allImages = glob.sync(`${inputDir}**/*.png`, {
  nodir: true,
  absolute: false
});
const widths = [100, 200, 300, 400, 500, 600, 700, 800, 900, 1000];
const buildImages = () => {
  widths.map((width, i) => {
    console.log(`Resizing to ${width}`)
    allImages.map(async (image) => {
      try {
        const imgFullName = path.basename(image);
        const imgExt = image.substr(image.lastIndexOf("."));
        const imgName = imgFullName.replace(imgExt, "");
        const outputName = imgName + "_" + width + "w" + imgExt;

        const destination = image
          .replace(inputDir, outputDir)
          .replace(imgFullName, outputName);

        await sharp(image)
          .resize(width)
          .toFile(destination);
      } catch (error) {
        console.log(`${image} error`, error);
      }
    });
  });
};
var allSvgs = glob.sync(`${inputDir}**/*.svg`, {
  nodir: true,
  absolute: false
});
const moveSvgs = () => {
  allSvgs.map(async image => {
    try {
      const imgFullName = path.basename(image);
      const imgExt = image.substr(image.lastIndexOf("."));
      const imgName = imgFullName.replace(imgExt, "");
      const outputName = imgName + imgExt;

      const destination = image
      .replace(inputDir, outputDir)
      .replace(imgFullName, outputName);

      fs.copyFile(image, destination, (err) => {
        if (err) throw err
      });
    } catch (error) {
      console.log(`${image} error`, error);
    }
  });
};

buildImages();
moveSvgs();