handy-service/scripts/build.js

> service for handy-cli

process.env.BABEL_ENV = "production";
process.env.NODE_ENV = "production";

process.on("unhandledRejection", err => {
  throw err;
});

require("../config/env");

const path = require("path");
const chalk = require("chalk");
const fs = require("fs-extra");
const webpack = require("webpack");
const formatWebpackMessages = require("react-dev-utils/formatWebpackMessages");
const printHostingInstructions = require("react-dev-utils/printHostingInstructions");
const FileSizeReporter = require("react-dev-utils/FileSizeReporter");
const printBuildError = require("react-dev-utils/printBuildError");
const paths = require("../config/paths");
const config = require("../config/webpack.config.prod");

const { measureFileSizesBeforeBuild, printFileSizesAfterBuild } = FileSizeReporter;
const useYarn = fs.existsSync(paths.yarnLockFile);

// These sizes are pretty large. We'll warn for bundles exceeding them.
const WARN_AFTER_BUNDLE_GZIP_SIZE = 512 * 1024;
const WARN_AFTER_CHUNK_GZIP_SIZE = 1024 * 1024;

// First, read the current file sizes in build directory.
// This lets us display how much they changed later.
measureFileSizesBeforeBuild(paths.appBuild)
  .then(previousFileSizes => {
    // Remove all content but keep the directory so that
    // if you're in it, you don't end up in Trash
    fs.emptyDirSync(paths.appBuild);
    // Merge with the public folder
    copyPublicFolder();
    // Start the webpack build
    return build(previousFileSizes);
  })
  .then(
    ({ stats, previousFileSizes, warnings }) => {
      if (warnings.length) {
        console.log(chalk.yellow("Compiled with warnings.\n"));
        console.log(warnings.join("\n\n"));
        console.log(
          `\nSearch for the ${chalk.underline(
            chalk.yellow("keywords")
          )} to learn more about each warning.`
        );
        console.log(
          `To ignore, add ${chalk.cyan("// eslint-disable-next-line")} to the line before.\n`
        );
      } else {
        console.log(chalk.green("Compiled successfully.\n"));
      }

      console.log("File sizes after gzip:\n");
      printFileSizesAfterBuild(
        stats,
        previousFileSizes,
        paths.appBuild,
        WARN_AFTER_BUNDLE_GZIP_SIZE,
        WARN_AFTER_CHUNK_GZIP_SIZE
      );
      console.log();

      const appPackage = require(paths.appPackageJson);
      const { publicUrl } = paths;
      const { publicPath } = config.output;
      const buildFolder = path.relative(process.cwd(), paths.appBuild);
      printHostingInstructions(appPackage, publicUrl, publicPath, buildFolder, useYarn);
    },
    err => {
      console.log(chalk.red("Failed to compile.\n"));
      printBuildError(err);
      process.exit(1);
    }
  );

// Create the production build and print the deployment instructions.
function build(previousFileSizes) {
  console.log("Creating an optimized production build...");

  const compiler = webpack(config);
  return new Promise((resolve, reject) => {
    compiler.run((err, stats) => {
      if (err) {
        return reject(err);
      }
      const messages = formatWebpackMessages(stats.toJson({}, true));
      if (messages.errors.length) {
        // Only keep the first error. Others are often indicative
        // of the same problem, but confuse the reader with noise.
        if (messages.errors.length > 1) {
          messages.errors.length = 1;
        }
        return reject(new Error(messages.errors.join("\n\n")));
      }
      if (
        process.env.CI
        && (typeof process.env.CI !== "string" || process.env.CI.toLowerCase() !== "false")
        && messages.warnings.length
      ) {
        console.log(
          chalk.yellow(
            "\nTreating warnings as errors because process.env.CI = true.\n"
              + "Most CI servers set it automatically.\n"
          )
        );
        return reject(new Error(messages.warnings.join("\n\n")));
      }
      return resolve({
        stats,
        previousFileSizes,
        warnings: messages.warnings
      });
    });
  });
}

function copyPublicFolder() {
  fs.copySync(paths.appPublic, paths.appBuild, {
    dereference: true,
    filter: file => file !== paths.appHtml
  });
}