How To Run WebDriver Tests in Parallel? 

Parallel testing can be done manually or with the help of test automation solutions. The concept of running several tests simultaneously on various browser configurations and devices is one that developers and testers frequently use. We mix the automation framework with cloud-based services and virtualization in parallel testing. We can scale automated tests across platforms in Parallel because this handles device management.  You can also conduct parallel testing in Selenium WebDriver.

Virtual machines are used to run testing in Parallel. A virtual machine is a computer resource that uses software to run applications instead of a real computer. Additionally, within an application window on a desktop, a virtual machine simulates the appearance and functionality of a completely different computer.

Due to the growing variety of devices and browsers that customers use, it could take time to carry out effective cross-platform testing quickly.

What does “Parallel Testing” in Selenium mean?

We can run tests simultaneously across several browsers and environments using Selenium Grid. It enables the user to perform automatic cross-browser testing simultaneously across various browsers and the corresponding versions for each browser. The main objective while running activities in Parallel is to cut down on the overall time and work needed for testing without sacrificing the overall quality of the result.

Building different projects to test browser compatibility in various web application components and a master project to test all of those distinct projects is the best technique for carrying out parallel testing. To conduct parallel testing in Selenium WebDriver, two criteria—the entry-level and exit-level—must be met.

Entry-level Requirements:

The entry-level requirements for parallel execution include the following:

• Setting up the testing environment is necessary before starting parallel testing in Selenium webDriver.
• Before automating the testing of browsers, ensure that you thoroughly understand all the prerequisites and circumstances.
• Both newly developed data and previously created data should successfully migrate.

Exit-level Requirements

When each of the following is satisfactorily completed, the exit-level criteria are met:

• The newly created software version must be tested alongside the old version.
• Learn about the main variations between the two applications.
• The same automated browser testing cycles should be repeated using the same inputs.
• The output of the more recent and older software versions should be measured, and the results should be compared.
• Please communicate any concerns or problems you find to the development staff.

We can deliver the application more quickly without compromising its quality because Selenium is utilized for parallel testing, especially when it comes to testing across browsers. When Selenium Grid is used for parallel testing, test scripts can be executed accurately with a high level of precision. 

Benefits of Parallel Testing: 

• A quicker rate of execution

Automation code could run simultaneously on various platforms, speeding up the process instead of spending tens or hundreds of hours manually testing the program or executing a script on a single set of devices. This contrasts with performing manual testing or scripted operations on a specific set of devices.

• An affordable cost

The cost of renting time on a cloud service is quite affordable compared to the expenses of maintaining an infrastructure made up of numerous devices.

• Broadens and deepens the scope of test coverage

Parallel testing is extremely compatible and enables us to test a wide range of different combinations and scenarios.

• Improve CD/CI

The continuous integration and development process can be optimized with its aid because it supports quick and frequent execution.

When should parallel testing be carried out?

We have the choice to run parallel tests when any of the following conditions apply to our project:

If we publish an upgraded version of the program that is equivalent to an earlier version of the app in terms of functionality. Since financial applications, like banking, are frequently the same, parallel testing with Selenium can be used to evaluate numerous iterations of these applications.

When we move legacy data from one system to another, another firm, or even a newer system. When testing the software program across various hardware, software, and browsers required.

Some of the best practices for testing in Parallel:

• Establish a cloud infrastructure

We can only make independent expenditures in various hardware, software, and mobile devices if we need to run a lot of scenarios in a short amount of time. On the other hand, cloud infrastructure is billed based on usage. It would be easy for us to set up numerous virtual machines to run scripts simultaneously before deactivating them after we had tested the scripts’ operation. There won’t be any recurring expenses for the infrastructure as a result.

• Investigating and enhancing the test suite

It is required to include test cases to increase test coverage. To efficiently prepare a parallel test, though, we must set priorities. Regarding the code’s complexity and the application’s crucial components, we must choose tests covering the software’s dangerous facets.

• Ensure the atomicity of your test scripts

By limiting the test script’s scope of exploration to a single scenario, we can more clearly state the test’s goal. It will be helpful to us in precisely documenting the flaws and in reminding us of the process’ ultimate goal.

• Programs for autonomous tests

None of these devices must rely on the others because we use many in tandem. Therefore, autonomous test scripts may reduce the number of test cases stuck while being executed.

• Ensure that tests proceed quickly

We must ensure that the time spent testing each script in the local environment stays within one minute.

• Data management

We need to ensure that every script produces test data in the same format it was when it was first developed to avoid problems with the functionality of other tests.

• Avoid using “hard coding.”

Embedding data directly into the code, instead of creating it at runtime, is called “hard coding.” It is conceivable for it to form dependencies between several test cases, which would make the parallel execution procedure more challenging. We will need to use a data-driven approach to set up our test cases for parallel execution appropriately.

Disadvantages of Parallel Testing

There are disadvantages to anything, and parallel testing is no exception. These disadvantages are as follows:

Fails for dependent modules: The simultaneous execution of multiple independently running modules is made possible by parallel testing. Dependent modules have a chance of failing the test. As a result, we cannot proceed with modules dependent on one another, which frequently occurs throughout testing. As a result, we have two options: either we disintegrate our independence, which takes more time and work, or we operate serially.

Knowledge of the Program Flow: To build parallel testing modules, the tester must have a firm grasp of the program’s flow. A single, seemingly unimportant interdependency has the power to interrupt the execution of all test cases. The tester must also know which modules should be executed in the same thread as others, which ones should be run in other threads, etc.

The fact that we can complete projects more quickly thanks to parallel testing in using Selenium webDriver is a tremendous help in this immediate and continuous delivery working environment, which is challenging in and of itself.

What are some of the challenges faced when testing in Parallel?

Concerns with test execution

When faced with such issues for a single machine running automation scripts, we take various actions, such as making code changes, upgrading or downgrading the browser, switching to a different package, etc. When we experience issues with execution, we act in this manner. What takes place if we run across this issue when parallel testing? These procedures must be carried out on various hardware, software, and virtual machines. It has the potential to be extremely exhausting if not done properly.

Resource management 

We must carefully plan everything out to do parallel testing for our project. For instance, we should know how many tests we must run simultaneously, how many browsers, how much RAM we need, how many testing hours we must complete, and how long our system must be locked throughout this process. We should also do a lot of other preparations before we start the test.

Reduce or eliminate dependence

We must create modules that are independent of one another because numerous modules operate concurrently in parallel testing. Modules that depend on other components cannot be included in the test suite.

Automation knowledge

We must thoroughly understand the products’ functionality to conduct parallel testing efficiently. We, therefore, want a parallel testing expert with extensive experience in automation who also has a thorough understanding of the project.

Issues with several browsers

Although parallel testing can help us perform cross-browser compatibility testing, it only covers a small number of browsers. Parallel testing may be beneficial.

Conclusion

Parallel testing is superior to sequential testing because sequential testing can generate delays for the team. In contrast, parallel testing can minimize those delays without decreasing the quality of the product being tested. We can lower costs, run scenarios with many concurrent users, improve our CI/CD process, and update the script frequently to get better outcomes. Utilizing a cloud-based environment, avoiding hard coding, designing separate test cases to eliminate data reliance, and remembering to write your scripts with parallel testing in mind are some strategies you should employ to get the most out of parallelization.

LambdaTest is a cloud-based platform.  If you leverge this tool, it allows you to test your web applications and websites across various browsers, operating systems, and devices. It provides a wide range of browsers and devices to choose from, and allows you to run parallel tests to speed up your testing process.

In parallel testing, multiple tests are run simultaneously on different browsers, operating systems, or devices. This can help you save time and resources, as it allows you to test your application on multiple configurations in a shorter time frame.

To run parallel tests on LambdaTest, you can use their Selenium Grid, which allows you to run tests in parallel on different machines, using different browsers and operating systems. You can also use their Scaling Plans, which allow you to run tests on multiple virtual machines in parallel, and scale up or down as needed. LambdaTest also provides integrations with popular testing frameworks such as WebDriver, Protractor, and Appium, which makes it easy to run your tests on their platform.