The proper functioning of the user interface is highly essential to ensure that your web application remains appealing to the audience.

A simple user interface helps the visitors to complete the introductory goals in just a few steps. Market experts believe that a functional user interface is critical for the success of a web application. It is directly linked to bounce rates and audience retention rates. Bounce rates calculate the total number of users who abandon your website after only visiting once. On the other hand, user retention rates calculate the total number of users who continue to use your website. They form an integral part of a loyal audience space. This is where tools like Google Puppeteer act as a lifesaver.

In the present Software Development Industry, the developers can use various test automation frameworks. They verify the proper functioning of the user interface. Google Puppeteer is one such test automation tool. It helps the developers to automate the Chrome Window for running various UI test cases. Since this automation tool is relatively new to the test automation industry, various developers are still uncertain about its capabilities and implementations. In this article, we are going to discuss everything that you need to know to get started with Puppeteer testing.  However, we will begin our discussion based on Puppeteer.

What is Puppeteer

The development team for Puppeteer is the same team that has developed the Google Chrome web browser. This fact is enough to justify that this automation tool used properly maintained in the long run.  Using this tool, developers can perform all the common and basic actions on the chromium Browser. Puppeteer uses the JavaScript programming language to execute all the basic test cases. One of the major advantages of Puppeteer is that it uses an easy-to-implement API to perform all the test cases. In simple terms, we can define it to be a Node library that helps the developers to control the headless Chrome over the dev tools protocol.

Basic Use Cases of Puppeteer

Before understanding how to begin testing with Puppeteer, the developers must have a proper idea about all the limitations of this automation tool. So, let us discuss all the functions that you can perform with Puppeteer:

• It can help you to extract a specific set of data or elements from any given website.
• This tool can help the developers to generate multiple screenshots of a website including Canvas and SVG.
• Using this tool, the developers can transform their website into PDF files.
• It is very easy to crawl a single-page application with the help of Puppeteer.
• Puppeteer uses the standard DOM API to access multiple websites and extract the required information according to the requirements of the developer.
• It can help the developers to generate various pre-rendered content including server-side rendering.
• The developers can also use Puppeteer to automate the form submission process. It usually helps to ensure that the website remains stable when the user is submitting a form.
• Puppeteer can help automatically analyze the performance of the web application depending on various user interactions.
• Similar to Cypress, it can also help to automate a user interface testing process.
• One of the major functions of this automation tool is to verify the validity and proper performance of multiple Chrome extensions.

One thing that developers must remember is that the functions of Puppeteer are nothing new compared to the traditional approach of Selenium or PhantomJS.  The only difference is that it uses a simple and easy-to-understand approach for accomplishing these goals. It also helps the developers to get rid of multiple worries regarding various minor details that they might encounter during the testing process.

The active maintenance of Puppeteer ensures that the developers receive a stable flow of updates according to the recent versions of the Chromium Browser.

Prerequisites for Puppeteer Testing

To properly work with Puppeteer, the developers must have the basic knowledge of programming languages like JavaScript, ES6+ and Node.js. The developers also must ensure that they have the latest version of node.js available on their system.  You will also have to install yarn on your system.  We will use it for reference throughout the article.

1. The Installation Phase

For the developers to start using Puppeteer, they have to use the “yarn add Puppeteer” command in their terminal window. One thing that is important to note is that during the download phase, Puppeteer will automatically download the latest version of the chromium Browser. This version is guaranteed to function with the Puppeteer API. However, the developers also have the liberty to completely skip this extra download process. For this process, they have to use the ‘core’ command during the adding phase.

The “puppeteer-core” is a lightweight version of Puppeteer. Using this library, the developers can use an existing Browser version or even conduct the test cases on a remote server. However, the developers must verify that the core version is compatible with the browser version that they intend to use it on. This is because the present core version is based on the 1.7.0 Version of Puppeteer.

2. Usage of Puppeteer

Puppeteer requires at least the 6.4.0 version of Node.js to function properly.  However, the developers will require the 7.6.0 version of Node.js if they wish to use await/async in their scripts. Let us use the example of generating a screenshot of Unsplash using Puppeteer to understand the usage pattern of this automation tool:

As we already said, it is very easy for developers to use Puppeteer for testing purposes.  the first step in this process is to create a screenshot.js file. The developers must remember that the file must be present in the root directory of the main project. After creating the primary code, it is time to acquire the puppeteer package. The Launch method will help the developers to initiate the package. After this, the developers have to wait for the package to finally get the browser instance.  The screenshot will be saved as unsplash.png. It will be present in the main project after 5-10 seconds.

Need for Tools and Platforms

Tools and platforms play a vital role when it comes to increasing the efficiency of automation test cases. However, it becomes a serious concern when the developers have to choose the perfect tool among the thousands of options available in the present market. The best remedy for this problem is to have a proper understanding of all the requirements based on the personal and business perspective. When it comes to the personal perspective, the developer must have a proper idea about the experience and knowledge of multiple programming languages and preferences. On the other hand, the business perspective involves the company budget, expected deadline and specific requirements of the development project. We can use the example of LambdaTest to further elaborate on this concept:

LambdaTest is a cloud-based test automation platform to test the cross-browser compatibility of websites and web applications. In simple terms, cross-browser testing is the process of ensuring that the web application remains functional irrespective of the browser version, operating system or the physical specifications of the device. LambdaTest helps the developers to render their Puppeteer test scripts on cloud.

Let us discuss some of the Unique advantages of a running Puppeteer test scripts on LambdaTest:

1. The Ability to run Puppeteer Headless Testing on a Cloud Grid

LambdaTest allows the developers to perform live testing on cloud grid.  LambdaTest also allows the developers to conduct the test cases on older and newer versions of the Chromium browser simultaneously. This is also one of the primary reasons why it produces highly accurate and dependable test results.

2. Boosting the Puppeteer testing Speed by Almost 50 times

Due to the competitive nature of the web application Development Industry, the developers cannot afford to drift away from their estimated deadline. During the early years of software development, companies used to take almost 5 days the complete all the test cases. However, with the advancement of technology and the use of automation testing, this time has come down to almost less than 2 days. LambdaTest further helps to reduce the testing period for Puppeteer testing by using parallel test cases on more than 50 different Browsers and operating systems. Parallel testing helps the developers to initiate multiple test instances simultaneously. It also helps to quickly release the final product by reducing the development feedback time exponentially.

3. Use of HyperExecute- One of the fastest Test Execution Platforms in the Market

HyperExecute is a modern test execution platform that is specifically designed for the modern agile quality assessment teams.  One of the major benefits is that it helps to match the cloud test speed with local test cases. It also helps to reduce that test cost that is almost similar to a flexible spot instance cloud. We can easily say that this technology is the future of the web application Development Industry.

Another important process in the tool’s selection stage is to verify the trustworthiness of any tool before integrating it with the primary web application development framework. Experts suggest that the simplest way to accomplish this goal is to look for multiple user reviews on online forums. This forum consists of multiple user reviews from developers who are currently using your target test automation tool. For reference, LambdaTest has millions of positive reviews from users all over the world.

The Conclusion

In this article, we discussed all the basic functionalities and requirements that the developers must be aware of for implementing Puppeteer testing. For a better understanding of the readers, we used the example of a dummy project. Recently, Puppeteer released the second version of its automation tool. Experts believe that it is the perfect alternative to automate small tasks using an easy-to-use API. The official website of this tool also consists of multiple explanations and documentation for the understanding of new developers. The explanations also consist of multiple examples to better elaborate the understanding process. The developers should also have a proper idea about the importance of choosing the perfect tool for their requirements. The combination of the perfect tool and adequate knowledge of Puppeteer can help developers to document functional UI test cases.