Application programming interfaces (APIs) are a crucial tool for organizations seeking smooth migration to the cloud. Enabling software to talk directly to software, they are the key to creating cloud-based solutions that are affordable, flexible, scalable and secure.

For organizations to have confidence in their cloud infrastructure and realize its full value, it’s vital to test these APIs. This is where automating your API testing comes in. Automated API tests deliver cost and time savings while managing the business risks of cloud migration around data loss, performance, security breaches and more. Here’s how.

What are the benefits of automating API testing?

APIs are how different applications communicate with each other to share data and services. They let developers make easy work of accessing and combining digital assets to connect different business processes and systems – on premises, in the cloud and a combination of the two.

No surprise then that API testing is critical in determining that all the disparate components – internal and external – across your technology environment are talking to one other properly and present no business risks. This includes your legacy systems, current-generation software and any emerging technologies, such as artificial intelligence and machine learning.

Manual testing of APIs is a poor match for the sheer volume of APIs within the typical organization. It also can’t keep pace with the iterative approach of most agile development teams and the continuous delivery demands of DevOps practices. Automating your API testing can, enabling you to power up your migration to the cloud by letting you:

  • Run tests more frequently and faster.
  • Provide feedback to your developers more frequently and faster.
  • Identify bugs and defects earlier.
  • Create test suites that are easy to maintain and reuse.
  • Simplify validation of the business logic, security, compliance and performance aspects of your apps and assets.
  • Cut the number and severity of faults passed on to end users.

This saves you time, money and a whole heap of hassle around regression testing checking that new features haven’t broken existing functionality. Indeed, as APIs have no graphical user interface (GUI) – so no buttons, menus, images or text to worry about – they are ideally suited to testing automation. The secret is mastering the test automation pyramid.

APIs and the test automation pyramid

The test automation pyramid is a model that outlines a more efficient approach to test automation. It is designed to ensure speed, quality and return on investment.

This pyramid consists of three distinct layers:

  1. At the base, unit tests – these focus on testing very small components or single pieces of functionality.
  2. In the middle, integration tests – these validate interactions with components that are external to the application, such as databases and external services.
  3. At the top, end-to-end tests – which test the functionality and performance of an application from start to finish as it would appear to a real user.

The ideal test automation suite creates a broad base for your pyramid by placing the greatest emphasis on testing the bottom two layers. This is where API testing comes in. API testing sits in the middle tier of the pyramid, integration testing, and bypasses the GUI, the part of an application that is visible to a user.

Why it’s better to automate API tests than user interface tests

Why does avoiding the user interface matter? As GUI tests involve buttons, menus and user input fields, automated versions of these tests are slow and fragile to run and tricky to maintain. Too often, they also fail to provide verification of an application’s core business logic and back-end functionality.

By contrast, APIs lack a GUI, making automated tests quicker, simpler, more stable to run and much easier to maintain. What’s more, APIs are the primary interface for application logic. So, while it’s still vital to run GUI tests checking user experience and accessibility, for example, the more you’re able to test at the API level, the swifter you’re able to deliver better software.

In a nutshell, automating your API tests will give you faster and greater test coverage that goes right to the heart of verifying integration of your applications and cloud infrastructure.

What does API testing involve?

The purpose of API Testing is to validate your APIs by checking their functionality, reliability, performance and security in isolation, and as part of end-to-end transactions during integration testing. This involves using software to send calls, or requests, to a single or sometimes multiple API endpoints to get output, and then note the response.

In essence, these tests check that APIs:

  • Return the correct response in the expected format for a broad range of likely requests
  • React correctly to edge cases, or unexpected or extreme inputs
  • Respond within an acceptable timeframe
  • Respond appropriately to potential security attacks

Again, the key factor here is that how things look is of no concern because APIs lack a GUI; what matters is validating the business logic of the application.

It is also worth noting that service virtualization is often used in API testing. This is to either isolate the service under test or expand the testing environment by simulating APIs or services that are missing or unavailable for testing purposes.

What are APIs?

To understand what makes automating API testing so critical, let’s take a closer look at what APIs do, how they work, and how this relates to cloud migration.

In a nutshell, APIs are all about communication; they act as the go-betweens or sets of rules that enable apps and services to talk to other apps and services and share data or functions. APIs do this by defining the calls, or requests, that can be made, how to make requests, and the data formats that can be used between the two systems.

This makes APIs an ideal mechanism for developers to connect different components by using one piece of software to call another. In short, if developers want to build something into their application that already exists elsewhere, APIs save them having to reinvent the wheel and build the resource from scratch themselves.

An everyday example of this is the weather app on your smartphone that uses the API of a third party to supply you with localized forecasts. Or the APIs provided by the Google Maps Platform that many shops, venues and mobile fitness apps use to provide location services.

How do APIs work?

You can think of an API as the waiter in your favorite restaurant who acts as the interface between you the hungry customer and the kitchen. The waiter takes your order, ensures you receive the right food and pay the bill while shielding you from the stuff you don’t need to worry about around cooking the food and washing the dishes.

APIs work in the same way, simplifying programing by giving developers only the information they need to make integration between separate software as smooth and efficient as possible.

APIs and cloud migration

How does this relate to cloud migration? First, by connecting software to software, APIs are the building blocks for modular cloud-based applications that are easy to maintain, update and scale. In short, APIs let developers make light work of microservices, an architectural approach to creating cloud applications arranged as collections of small, self-contained pieces of business functionality.

Second, APIs are the key that unlocks and modernizes organizations’ most precious hard assets, their existing data and technology investments. In a nutshell, it’s APIs that liberate organizations’ legacy functionality and data from their various silos and repackages them for new uses by integrating cloud-based systems with on-premises or private cloud workflows.

Many of the cloud services we use every day rely on numerous different interconnected APIs. Testing these APIs early in the development lifecycle helps identify issues and avoids the impact of them failing in a later testing phase when any bugs or faults can be both time-consuming and costly to fix.

Key takeaways

Today, APIs are a critical component of every digital transformation initiative that involves moving to the cloud. From public and private clouds to hybrid and multi-cloud environments, APIs are the catalysts for a modern approach to software development that converts monolithic applications to a microservices approach. This makes API testing a vital part of your business strategy.

As more companies adopt agile workflows and shift left toward DevOps practices, testing feedback needs to be more frequent and faster than ever. Automated testing that focuses solely on the user interface is notoriously slow and can thwart your continuous integration and delivery efforts.

Automating your API testing, however, will give you quicker and greater test coverage, saving you time and money while speeding up your migration to the cloud.

Your next steps

It’s crucial that your automated API testing goes beyond checking technical capabilities to align with the business context of your cloud migration project. This includes mitigating any business risks and closing security loopholes to prevent them becoming problems or, indeed, disasters that damage your reputation and brand.

Qualitest’s experts are specially trained in Agile, DevOps, REST and SOAP and are ready to help you develop an automated API testing strategy that fits your specific business requirements. Whether you are building your own APIs or trying to integrate with APIs, they will make sure that your cloud migration is smooth, fast and efficient. So, don’t be shy, get in touch.

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