Adding copy to clipboard functionality in Angular application

Today, I had to work on an application that required copy to clipboard functionality. Below is a step by step tutorial that will help you add copy to clipboard functionality. The reason I had to implement copy to clipboard functionality is that with dnd-list copy feature gets broken so I needed a way to give user a copy functionality.

Angular version being used in Angular 5.

Step 1: Create Angular application

$ ng new myapp

Step 2: Install ngx-clipboard and ng2-toastr

$ npm install --save ng2-toastr ngx-clipboard

Step 3: Configure modules

In the app.module.ts, add ClipboardModule and ToastModule

import { ToastModule } from 'ng2-toastr/ng2-toastr';
import { ClipboardModule } from 'ngx-clipboard';
    imports: [
    declarations: [
    bootstrap: [AppComponent]
export class AppModule { }

Step 4: Add ngx-clipboard directive

Update app.component.html

<div class="col-11 p-2 lh-condensed">
      <h6 class="font-weight-bold">
        <div class="float-right">
          <i class="ft-chevron-down"></i>
          <div class="dropdown-menu">

Update app.component.html

  copyToClipboard() {
    this.toastr.success('Copied to clipboard', 'Success!');

Adding autofocus to an input field in an Angular 5 Bootstrap 4 application

A couple of days back I faced trouble adding autofocus to an input field that was rendered inside a Bootstrap modal. The project is built using Angular 5 and Bootstrap 4. Also, I was using ng-bootstrap component library. The issue was that input field was auto focussed only the first time I opened the modal. In subsequent requests, the input field was not auto-focussed. It took me sometime to figure out why this is happening and how to fix the problem. In this quick post, I will walk you through how to enable autofocus in an input field in an Angular 5 Bootstrap 4 application. Continue reading “Adding autofocus to an input field in an Angular 5 Bootstrap 4 application”

Updating Angular Projects Generated By Angular CLI To Latest Version

Today, I wanted to update one of my starter projects to use the latest version of Angular. I built starter project with Angular 5.0.0 and I wanted to update it to latest Angular version which is 5.0.4. Below are the steps, you need to follow to update your project. Navigate to your project working directory and do the following:

Step 1: Remove node_modules

$ rm -rf node_modules/

Step 2: Update angular-cli dependency to latest version

You can check latest version at

Once you know the version, update the @angular/cli version in the package.json to the latest version.

Step 3: Install and run the upgrade

$ yarn install
$ yarn upgrade

yarn upgrade will update all the dependencies to the latest version.

Step 4: Run the application

Now, you can run the application using the yarn start -o command.

A Minimalist Guide to Building Spring Boot Angular 5 Applications

Over the last year, I have worked with many teams using Spring Boot with Angular/React for developing Java web applications. I consider Spring Boot a pragmatic opinionated way to build Spring applications. Spring Boot makes it easy to build web applications in Java and provides a productive environment for development.
Continue reading “A Minimalist Guide to Building Spring Boot Angular 5 Applications”

Building Newsletter to PDF Utility With Puppeteer, Hummus , and Cheerio

Today, I had an idea to build a command-line utility to convert technical newsletter like hackernewsletter to PDF. This will enable me to read newsletter offline while travelling. After spending couple of hours, the first version of the utility is ready. In this post, I will share how I was able to quickly build the working version of the utility. While building, I learnt about couple of cool node modules that made it easy for me to build the utility. I was amazed by the rapid prototyping capabilities of the node ecosystem.

What we want to build?

We want to build newsletter-to-pdf utility that given a newsletter issue URL will generate a single PDF with all the content of the stories.

To build this utility, we need to perform following tasks:

  1. Given a newsletter URL, find all the story URLs.
  2. For each story URL, generate a PDF.
  3. Combine individual PDFs into a single PDF.

Step 1: Find all the story urls from a newsletter URL

Most newsletter allow users to view in a browser. For example, is the URL for issue #373 of hackernewsletter. Each newsletter has a set of stories that a reader can read. The first thing we have to do is to find all the URLs that correspond to a story.  To accomplish this task, I made use of Cheerio and request libraries. I used request-promise library so that I can use request with Promise API support. The code shown below extracts all the anchor tags whose title contains Votes text.

const rp = require('request-promise');
const cheerio = require('cheerio');
function extractLinksFromUrl(url) {
    var options = {
        uri: url,
        transform: function (body) {
            return cheerio.load(body);
    return rp(options)
        .then(function ($) {
            const links = $('a').filter(function (i, el) {
                const titleAttr = $(this).attr('title');
                return titleAttr && titleAttr.includes('Votes');
            console.log('links', links.length);
            return $(links).map((function (i, link) {
                return new Story($(this).attr('href'), $(this).text());
        }).catch(function (err) {
            console.log('Encountered error ', err);

class Story {
    constructor(url, title) {
        this.url = url;
        this.title = title;

Step 2: Generate PDF for each story

Next step is to generate PDF for each story.  For this I made use of Google’s puppeteer module. Pupeeter is headless Chrome Node API that you can use to generate PDFs, screenshots, scrape content of website etc.

async function generatePdf(url, outputDir, filename) {
    const browser = await puppeteer.launch();
    const page = await browser.newPage();
    await page.setRequestInterceptionEnabled(true);
    page.on('request', request => {
        if (request.url.includes('disqus'))
    await page.goto(url,
            waitUntil: 'networkidle',
            networkIdleTimeout: 5000,
            timeout: 3000000
    await page.pdf({
        path: path.join(outputDir, filename),
        format: 'A4'

    await browser.close();

In the code shown above we use standard Puppeteer API to generate PDF for a URL. One thing that you would notice is the use of request interception. Puppeteer allows you to intercept the request and you can decide whether you want to make the request or not. This gives you the flexibility to block ads or comment sharing sites like disqus. I aborted all the requests to disqus as I only care about article content.

Step 3: Combine the individual stories into one PDF

It took me sometime to figure out how to do it. After step 2, I was able to generate PDF for each story URL. I wanted to generate a single PDF for the entire newsletter content. This means I have to merge all the PDFs into one. After a bit of googling, I was able to find a library with name hummus. Hummus is a node module for creating, parsing, and modifying PDFs. I relied on its ability to append a PDF to a target PDF. In this code shown below, we created a new PDF file and appended pages of an existing PDF to it. This made it feasible to create a single PDF with all PDFs content.

function combinePdfs(files){
    const pdfWriter = hummus.createWriter('newsletter.pdf');
        .filter(file => file.endsWith(".pdf"))
        .forEach(fn => {


I will publish the node module in next few days after polishing it a bit. Let me know what features you would like to have in this utility.


Amazon ECS: The Modern Cluster Manager Part 1

In the last few posts, we looked at various Docker utilities and how XL Deploy can make it easy for enterprises to adopt and use Docker. Docker streamlines software development and testing for teams that have started embracing it. The package once deploy anywhere (PODA) capability of Docker minimises the issue of environmental (like staging, quality assurance, and production) differences. Continue reading “Amazon ECS: The Modern Cluster Manager Part 1”