Whitepaper: How to Choose the Right API Testing Solution

Rapid development and releases are simply part of business today. Finding the right functional testing solution will help your business succeed.

Learn the key features that must be included in your API testing solution to ensure a successful rollout across your organization.


Download the whitepaper to understand the five key evaluation areas for choosing your functional test automation solution.

Focus areas:
  • What is API testing?
  • Today’s API testing tool landscape
  • 5 key capabilities you need in your API testing solution
  • API testing enables developers and testers to test the series of components that make up their application. Without API testing, they would be stuck manual testing, just like a user, testing the application at the UI level, waiting until the entire application stack is built before being able to start testing.
  • You can instead perform automated API testing by testing the application at the API level, designing test cases that interact directly with the underlying APIs, and gaining numerous advantages, including the ability to test the business logic at a layer that is easy to automate in a stable manner.
  • Testing earlier, at the API level, helps you “fail fast and fail early,” catching defects early at their source, rather than later in the software delivery process.
  • API tests can all be automated and run continuously, so you can ensure that your application is aligned to business expectations while also functionally precise.

API testing is integral for identifying defects at multiple layers of your application and ensuring a seamless customer experience, but there are many different approaches and tools available on the market. To get the ROI you’re looking for to achieve the necessary automation for delivering high quality software at the speed of Agile/DevOps, you need to choose the solution that’s right for the needs of your organization. The right API testing tool will help you address today’s challenges including omni-channel testing, test maintainability, microservices, difficulties reproducing defects and the impact of rapidly changing APIs.

  1. Lightweight tools

Free or open source help you get going quickly, create very simple smoke tests and apply basic validations. They’re often used by development teams to test in an ad-hoc way. Many open source tools are free in the short term but become more expensive when it comes to vendor support and maintenance.

  1. Enterprise tools

More powerful, vendor-supported tools enable daily testing of APIs, supporting a broader range of technologies. These comprehensive tools support complex DevOps workflows and easily scale across teams and organizations to enable continuous testing.

You should be able to meet your API testing requirements with a solution that’s easy to use, adopt and scale throughout the organization. Below we’ve summed up the most important capabilities across five key areas, but you’ll want to download the complete white paper for all the details.

1. Ease of use and core capabilities
  • Visual and scriptless functionality

Your API testing tool should not require you to have any experience writing code. A visual testing tool with an intuitive and scriptless user interface will empower a large body of testers at a variety of experience levels to use the tool productively.

  • A custom extensibility framework

Should you need to write code to accomplish tasks such as generating a proprietary token or a unique identifier, your API testing tool should have the capability of using the scripts, but it should not be limited to a single language.

  • Automated assertions and validations

It is important for your API testing tool to help you define success criteria for response validation. This process should enable the tests to run automatically as a batch, validate messages, and eliminate the need for you to manually inspect your traffic.

  • Data-driven testing

For maximum flexibility when working with your API testing tool, it should be able to data-drive your test cases. This means that your framework should enable you to swap out static values in your API calls with dynamic values derived from data sources.

  • Test reusability

Your API testing solution should be able to re-leverage any API test you have previously created. This gives you the ability to define scenarios such as web UI logins, complex authentication, or a repeated set of actions once and then bring them into subsequent test cases as a reference.

  • Ability to rapidly create tests before a service is available

It’s important to ensure that your API testing solution helps you rapidly create tests early in the software development process.

  • Authentication

Your API testing solution also needs to work with authentication, encryption, and access control.

2. Optimized workflows
  • Test flow logic

Your API testing tool should have a mechanism for controlling test flow based on conditions.

  • AI-powered test creation

Your API testing solution must be able to work in an Agile context.

  • Test data management/generation

Your API testing tool should support you in this activity by providing workflows for connecting to various data sources as well as generating test data itself.

  • Event monitoring

To enable end-to-end testing, your API testing solution must be able to monitor events as they flow through your system.

  • BDD support (Cucumber)

To support BDD, your API testing solution should give you the foundation for Cucumber step definitions that your QA team needs to build the required test steps for business analysts to leverage in their BDD.

3. Supported technologies
  • Rest API testing

Your testing tool must be able to interface with Representational State Transfer protocol (REST) APIs.

  • SOAP API testing

Simple Object Access Protocol (SOAP) is still extremely relevant in most applications, so your API testing solution must be able to interface with SOAP APIs.

  • MQ / JMS testing

Your API testing solution must support queuing technology such as MQ and JMS, so you can simulate various patterns including point-to-point and publish/subscribe.

  • IoT and microservice testing

Your API testing tool must be future-proof and have the ability to communicate via new protocols so that you are ready to test them as they are implemented at your organization.

  • Database testing

Your API testing tool must have the ability to communicate with databases. This will give you the ability to validate the contents of the database as you are interacting with your system via the APIs.

  • Web-based testing

Your API testing tool must have an integrated capability for testing your web UIs.

  • Performance testing

Your API testing solution should allow you to shift left performance testing by leveraging the API tests you have been creating for individual component, smoke, and regression tests as a part of your nonfunctional load and performance testing strategy.

  • Testing nonstandard message formats

Your API testing solution must be able to communicate over non-standard message formats and protocols.

4. Automation
  • CI integration

Your API testing tool should have the capability to integrate into your existing CI process, so you can execute test cases via a command line interface or a series of open REST APIs, and select which type of test cases you want to execute with a specific configuration.

  • Build system plugins

Your API testing solution should have built-in plugins for common CI systems such as Jenkins, Microsoft VSTS, Atlassian Bamboo, and Jet Brains Team City. There are other build systems available, so your API testing solution should have an extensibility platform to allow you to build connectors for all future CI systems.

  • Command-line execution

Your API testing solution should have the ability to execute your API tests in batch via a command line interface.

  • Open APIs for DevOps integration

Your API testing solution should have open APIs that allow you to programmatically generate, configure, and execute test cases.

5. Management and maintenance 
  • Integration with requirements management systems

Your API testing solution should integrate with requirements management systems such as ALM, Bugzilla, and Jira.

  • Basic and advanced reporting

Your API testing solution should have a rich reporting framework that allows you to understand individual API test results, as well as the entire project health.

  • Test orchestration

Your API testing solution should provide the ability to bundle together API testing scenarios for execution in multiple environments.

  • A process for managing change

One of the most critical capabilities of your API testing solution is a change-management process.

  • On-premise and browser-based access

Your API testing solution must be broadly available. This means that you should be able to access your solution either on-premise or through a cloud provider, and your API testing solution must have a desktop application as well as a browser-based application.

About Parasoft

Parasoft’s software testing solutions support the entire software development process, from when the developer writes the first line of code all the way through unit and functional testing, to performance and security testing, leveraging simulated test environments along the way. Parasoft's unique analytics platform aggregates data from across all testing practices, providing insights up and down the testing pyramid to enable organizations to succeed in today's most strategic development initiatives, including Agile/DevOps, Continuous Testing, and the complexities of IoT. Parasoft’s automated software testing innovations fuel software development organizations, helping teams reduce the time, cost, and effort of delivering high-quality software to the market.