Automatic version stamping with build number

build_number.json

{
    "buildNumber": 1
}

package-partial.json

{
  "scripts": {
    "prestart": "node version.js"
  }
}

version.ts

// See https://medium.com/@amcdnl/version-stamping-your-app-with-the-angular-cli-d563284bb94d

const { gitDescribeSync } = require('git-describe');
const { resolve, relative } = require('path');
const { writeFileSync } = require('fs-extra');

const moment = require('moment');

const { version } = require('./package.json');
var { buildNumber } = require('./build_number.json');

buildNumber++;

const gitInfo = gitDescribeSync({
    dirtyMark: false,
    dirtySemver: false
});

let prerelease = version.split('-');
let _version = prerelease.shift();
let [major, minor, patch] = _version.split('.');

if(gitInfo.dirty) prerelease.push('dirty');

let raw = [_version, ...prerelease].join('-');
let build = [buildNumber, gitInfo.distance, gitInfo.hash].filter(v => v).join('.');

// full: <version>[-prerelease][-dirty]+<buildNumber>.<distance>.<sha>

let versionInfo = {
  raw: raw, // '4.0.0-rc.6',
  major: major, // 4,
  minor: minor, // 0,
  patch: patch, // 0,
  prerelease: prerelease, // [ 'local' ],
  buildNumber: buildNumber,
  build: build, // 'sha.73808dd',
  version: version, // '4.0.0-local',
  // codeName: 'snapshot',
  // isSnapshot: true,
  full: [raw, build].join('+'), // '4.0.0-local+sha.73808dd',
  // branch: 'master',
  // commitSHA: '73808dd38b5ccd729404936834d1568bd066de81'
  hash: gitInfo.hash,
  buildDate: moment().format(),
};

const bnFile = resolve(__dirname, 'build_number.json');
writeFileSync(bnFile,
`${JSON.stringify({buildNumber:buildNumber}, null, 4)}
`, { encoding: 'utf-8' });

const file = resolve(__dirname, 'angular_src', 'environments', 'version.ts');
writeFileSync(file,
`// IMPORTANT: THIS FILE IS AUTO GENERATED! DO NOT MANUALLY EDIT OR CHECKIN!
/* tslint:disable */
export const VERSION = ${JSON.stringify(versionInfo, null, 4)};
/* tslint:enable */
`, { encoding: 'utf-8' });

console.log(`Wrote version info ${versionInfo.version} to ${relative(resolve(__dirname, '.'), file)}`);