# Creating an Angular npm library

How to publish your NgModule, written in TypeScript in npm registry. Setting up npm project, typescript compiler, rollup and continous integration build.

# Minimal module with service class

# File structure

/
    -src/
        awesome.service.ts
        another-awesome.service.ts
        awesome.module.ts
    -index.ts
    -tsconfig.json
    -package.json
    -rollup.config.js
    -.npmignore

# Service and module

Place your awesome work here.

src/awesome.service.ts:

export class AwesomeService {
    public doSomethingAwesome(): void {
        console.log("I am so awesome!");
    }
}

src/awesome.module.ts:

import { NgModule } from '@angular/core'
import { AwesomeService } from './awesome.service';
import { AnotherAwesomeService } from './another-awesome.service';

@NgModule({
    providers: [AwesomeService, AnotherAwesomeService]
})
export class AwesomeModule {}

Make your module and service accessible outside.

/index.ts:

export { AwesomeService } from './src/awesome.service';
export { AnotherAwesomeService } from './src/another-awesome.service';
export { AwesomeModule } from './src/awesome.module';

# Compilation

In compilerOptions.paths you need to specify all external modules which you used in your package.

/tsconfig.json

{
  "compilerOptions": {
    "baseUrl": ".",
    "declaration": true,
    "stripInternal": true,
    "experimentalDecorators": true,
    "strictNullChecks": false,
    "noImplicitAny": true,
    "module": "es2015",
    "moduleResolution": "node",
    "paths": {
      "@angular/core": ["node_modules/@angular/core"],
      "rxjs/*": ["node_modules/rxjs/*"]
    },
    "rootDir": ".",
    "outDir": "dist",
    "sourceMap": true,
    "inlineSources": true,
    "target": "es5",
    "skipLibCheck": true,
    "lib": [
      "es2015",
      "dom"
    ]
  },
  "files": [
    "index.ts"
  ],
  "angularCompilerOptions": {
    "strictMetadataEmit": true
  }
}

Specify your externals again

/rollup.config.js

export default {
    entry: 'dist/index.js',
    dest: 'dist/bundles/awesome.module.umd.js',
    sourceMap: false,
    format: 'umd',
    moduleName: 'ng.awesome.module',
    globals: {
        '@angular/core': 'ng.core',
        'rxjs': 'Rx',
        'rxjs/Observable': 'Rx',
        'rxjs/ReplaySubject': 'Rx',
        'rxjs/add/operator/map': 'Rx.Observable.prototype',
        'rxjs/add/operator/mergeMap': 'Rx.Observable.prototype',
        'rxjs/add/observable/fromEvent': 'Rx.Observable',
        'rxjs/add/observable/of': 'Rx.Observable'
    },
    external: ['@angular/core', 'rxjs']
}

# NPM settings

Now, lets place some instructions for npm

/package.json

{
  "name": "awesome-angular-module",
  "version": "1.0.4",
  "description": "Awesome angular module",
  "main": "dist/bundles/awesome.module.umd.min.js",
  "module": "dist/index.js",
  "typings": "dist/index.d.ts",
  "scripts": {
    "test": "",
    "transpile": "ngc",
    "package": "rollup -c",
    "minify": "uglifyjs dist/bundles/awesome.module.umd.js --screw-ie8 --compress --mangle --comments --output dist/bundles/awesome.module.umd.min.js",
    "build": "rimraf dist && npm run transpile && npm run package && npm run minify",
    "prepublishOnly": "npm run build"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/maciejtreder/awesome-angular-module.git"
  },
  "keywords": [
    "awesome",
    "angular",
    "module",
    "minimal"
  ],
  "author": "Maciej Treder <contact@maciejtreder.com>",
  "license": "MIT",
  "bugs": {
    "url": "https://github.com/maciejtreder/awesome-angular-module/issues"
  },
  "homepage": "https://github.com/maciejtreder/awesome-angular-module#readme",
  "devDependencies": {
    "@angular/compiler": "^4.0.0",
    "@angular/compiler-cli": "^4.0.0",
    "rimraf": "^2.6.1",
    "rollup": "^0.43.0",
    "typescript": "^2.3.4",
    "uglify-js": "^3.0.21"
  },
  "dependencies": {
    "@angular/core": "^4.0.0",
    "rxjs": "^5.3.0"
  }
}

We can also specify what files, npm should ignore

/.npmignore

node_modules
npm-debug.log
Thumbs.db
.DS_Store
src
!dist/src
plugin
!dist/plugin
*.ngsummary.json
*.iml
rollup.config.js
tsconfig.json
*.ts
!*.d.ts
.idea

# Continuous integration

Finally you can set up continuous integration build

.travis.yml

language: node_js
node_js:
- node

deploy:
  provider: npm
  email: contact@maciejtreder.com
  api_key:
    secure: <your api key>
  on:
    tags: true
    repo: maciejtreder/awesome-angular-module

Demo can be found here: https://github.com/maciejtreder/awesome-angular-module