Rework loopback-next infrastructure to remove top-level index files

fix-index-files.js

// Copyright IBM Corp. 2019. All Rights Reserved.
// Node module: loopback-next
// This file is licensed under the MIT License.
// License text available at https://opensource.org/licenses/MIT

'use strict';

const path = require('path');
const fs = require('fs-extra');

if (require.main === module) {
  fixIndexFiles().then(
    ok => process.exit(ok ? 0 : 1),
    err => {
      console.error(err);
      process.exit(2);
    },
  );
}

async function fixIndexFiles() {
  const Project = require('@lerna/project');

  const project = new Project(process.cwd());
  const packages = await project.getPackages();

  for (const p of packages) {
    await fixPackage(p, project.rootPath);
  }
}

async function fixPackage(p, rootPath) {
  // Skip JS-only projects like CLI
  const isTsProject = await fs.pathExists(
    path.join(p.location, 'tsconfig.json'),
  );
  if (!isTsProject) return;

  // 1. Remove top-level index files
  for (const i of ['index.js', 'index.ts', 'index.d.ts']) {
    await fs.remove(path.join(p.location, i));
  }

  const pkgJsonFile = path.join(p.location, 'package.json');
  const meta = await fs.readJson(pkgJsonFile);
  // 2. Update entry points
  // We want `main` and `types` to be among the first fields,
  // therefore we have to re-populate the object
  const newMeta = {
    name: meta.name,
    version: meta.version,
    description: meta.description,
    private: meta.private,
    main: undefined,
    types: undefined,
    ...meta,
  };
  newMeta.main = 'dist/index.js';
  newMeta.types = 'dist/index.d.ts';

  if (!newMeta.repository) {
    newMeta.repository = {
      type: 'git',
      url: 'https://github.com/strongloop/loopback-next.git',
      directory: path.relative(rootPath, p.location),
    };
  }

  // 3. Update package contents
  // Note that example packages don't have `files` section, the npm package
  // must include ALL files

  if (newMeta.files) {
    newMeta.files = newMeta.files.filter(f => !f.startsWith('index.'));
  }

  await fs.writeJson(pkgJsonFile, newMeta, {spaces: 2});
}