How API Monitoring Tools and Approaches Fit Into Continuous Testing

    Visibility into API issues is critical for developers to operate at their best in a continuous testing environment and most effectively optimize application performance. That's where API monitoring tools and approaches come in.

    What Are the Pieces that Make up Continuous Testing?

    Continuous testing is the process of applying several different testing practices to the software development lifecycle. Continuous testing can affect every single stage of development, from the initial ideation process, before code is ever written, to the requirements phase and customer journeys, and to DevOps and production tasks.

    There are several different practices that can be applied as part of a continuous testing transformation:

    • Test ideas (whiteboard prototypes, customer interviews)
    • Test-driven development (TDD)
    • Behavior-driven development (BDD)
    • Unit testing
    • Performance testing
    • Functional testing
    • API monitoring
    • UI testing
    • Security testing
    • Service virtualization

    In this post, we’re going to focus on API monitoring, and how it fits into the continuous testing puzzle.

    Why are API Monitoring Tools an Important Piece of Continuous Testing?

    There are a lot of different ways people describe APIs: “APIs are eating the world,” “APIs are the building blocks of the internet,” “APIs are the future,” and so on.

    No matter which perspective you think is most on target, APIs are more popular than ever, and can be used as building blocks in the development process to help teams build specific features with incredible ease and speed (think emailsSMS payment, among many other features).

    In big companies, it’s common to have internal APIs as well that are used and shared by multiple internal applications or provided to a limited number of partners.

    No matter the case, APIs are part of many applications built today. A big challenge with using APIs is that you might not always have access to the backend information of the API itself. As a result, when issues arise, it can be really hard to figure out what went wrong.Visibility into API issues is critical for developers and applications to operate at their best.That’s where API monitoring tools come in.

    API Monitoring and the Development Lifecycle

    API monitoring tools can be used to catch API and applications issues before customers do. The way teams can accomplish that is by creating API tests (or monitors) that run continuously and check if an API is:

    • Up
    • Returning the correct data
    • Performing well
    By shifting your API testing right, and running API tests continuously, you and your team can be the first ones to be notified if there’s something wrong with an API, so you can proactively work on fixing the issue and communicating with your users. Not only that, but since your API tests are run continuously, you can also compare responses from when the API was behaving correctly, so that when the API stopped working it can help you to track down the root cause of the issue.

    API monitoring is usually left to production environments, but it can also prove invaluable during other phases of the development process. The nature of API monitoring being a continuous running process means it can surface issues that might be really hard to replicate, whether that is in a testing, staging, or production environment. For example, monitoring APIs in a staging environment might surface issues caused by network traffic conditions that are hard to replicate, and that could happen in production as well. It can also surface simpler issues that unit tests might not catch, like an application that is not cleaning up its cache correctly.


    The transformation that teams and companies go through when applying a continuous testing philosophy to their processes can have a deep impact on every aspect of an application.

    Test-driven development can change the culture of an engineering team, and alter how developers work day-to-day, and help surface application issues earlier in the development process. Load testing can help teams gain more confidence that their applications can handle a certain volume of users and traffic, and prepare teams for events that will fuel an increase in those numbers. In addition, it can help teams determine how to handle unexpected events.

    API monitoring is another piece of the continuous testing puzzle. API monitoring tools can complement continuous testing best practices by helping teams more quickly catch the API issues that can cause serious disruptions to an application or business. In addition, these tools offer visibility into those issues so teams can respond and fix them quickly.