bin/build-module.js

#!/usr/bin/env node

// Build a single module using a generic Rollup-based build script.
// Reads in a src/index.js, writes to a lib/index.js. Might write
// index-browser.js if it detects that it needs to support a "browser" version.
//
// You can use this on the CLI by doing:
// build-module.js path/to/module

'use strict';

var rollupPrepublish = require('rollup-prepublish');

var path = require('path');
var lie = require('lie');
if (typeof Promise === 'undefined') {
  global.Promise = lie; // required for denodeify in node 0.10
}
var Promise = lie;
var denodeify = require('denodeify');
var mkdirp = denodeify(require('mkdirp'));
var rimraf = denodeify(require('rimraf'));

function buildModule(filepath) {
  var pkg = require(path.resolve(filepath, 'package.json'));

  if (pkg.browser && pkg.browser['./lib/index.js'] !== './lib/index-browser.js') {
    return Promise.reject(new Error(pkg.name +
      ' is missing a "lib/index.js" entry in the browser field'));
  }

  // browser & node vs one single vanilla version
  var versions = pkg.browser ? [false, true] : [false];

  // special case for "pouchdb-browser" - there is only one index.js,
  // and it's built in "browser mode"
  var forceBrowser = pkg.name === 'pouchdb-browser';

  return Promise.resolve().then(function () {
    return rimraf(path.resolve(filepath, 'lib'));
  }).then(function () {
    return mkdirp(path.resolve(filepath, 'lib'));
  }).then(function () {
    return Promise.all(versions.map(function (isBrowser) {
      var dest = isBrowser ? 'lib/index-browser.js' : 'lib/index.js';
      return rollupPrepublish({
        entry: path.resolve(filepath, './src/index.js'),
        dest: path.resolve(filepath, dest),
        browser: isBrowser || forceBrowser,
        quiet: true
      }).then(function () {
        console.log('  \u2713' + ' wrote ' +
          path.basename(filepath) + '/' + dest + ' in ' +
            (isBrowser ? 'browser' :
            versions.length > 1 ? 'node' : 'vanilla') +
          ' mode');
      });
    }));
  });
}
if (require.main === module) {
  buildModule(process.argv[process.argv.length - 1]).catch(function (err) {
    console.error('build-module.js error');
    console.error(err.stack);
    process.exit(1);
  });
} else {
  module.exports = buildModule;
}