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Testing of application programming interfaces(APIs) is one type of software testing to check if the functionalities, performance, security, and reliability are working as expected. API testing comes under integration testing. It involves testing APIs directly to determine whether APIs return the expected response for a wide range of requests and whether it reacts appropriately to failures, unexpected inputs, delivers responses in the expected time, and how it responds to potential security attacks.
APIs facilitate holistic service delivery across the application modules and set the communication channels. And, standard software development practices use these APIs as channels for service delivery in apps due to their many benefits like reduced time-to-market, streamlined SDLC cycles, and more.
There are several types of API testing, such as unit testing, functional testing, security testing, Web UI testing, load testing, penetration testing, and several more. Each type of testing involves a different set of goals, such as testing the functionality of individual operations or validating functionality and performance under load, etc.
Enterprises that are into custom software development services conduct these types of API testing using comprehensive strategies and build secure and reliable platforms for customers. However, certain challenges in API testing sometimes put hurdles in progress. Here we’ve listed the most commonly faced six major API testing challenges with their solutions to overcome them.
1. Initial Set-up of API Testing
You will have to go with automation testing for API testing to check their performance under pressure. And when it comes to setting up the automation testing initially for APIs, it takes considerable time and motivation to get the testing infrastructure up and running. Most times, teams give up halfway and get back to their traditional way of manual testing. Of course, once the first step is done, it really pays off in the long term, but it is challenging to keep your team motivated until this process is over successfully.
Solution: Get started API testing in the design phase itself and identify skilled resources for this task. Once the infrastructure and scripts are ready, check if the data and API requests are working as expected.
2. Updating API Schema
Schema is the formatting of data to handle requests and responses for the API. Maintaining these schemas is crucial during the test process. So any changes in the program creating additional parameters need to be reflected in the schema configuration. Unfortunately, updating these changes in API schema causes downtime.
Solution:
To avoid such downtimes, you should thoroughly test the APIs in beta and alpha environments. These environments are considered safe for this process.
3. Familiarity With APIs
Team members with less experience in the API testing approach find it challenging to get familiar with manual testing hurdles and running API test cases. In addition, teams lacking specific skill sets and training find it hard to accomplish satisfactory API testing, especially in tight deadlines where enterprises lack time to provide adequate training to the people.
Solution:
Make sure your testing teams have proficient knowledge and are provided comprehensive training on how APIs function and the project’s business logic.
4. Sequencing of API Calls
With more and more applications involved in API testing, the sequencing order of API calls becomes complicated and results in a sequencing challenge for the testing teams. API calls are the responses from APIs to API requests. For example, an API call to return a forgotten user id before user registration will return an error.
Solution:
To solve this problem, development teams should make flowcharts to visualize how the API calls occur. This will also make the process of building and integrating API calls faster.
5. Use Case Propagation
API testing involves near-infinite use cases since it is the central hub of business logic and gateway to data for interfacing applications. This sometimes challenges team members’ competencies in designing the test cases since the number of tests required exceeds many.
Solution: One of the solutions to this problem is to prefer automating API tests and integrate them into a continuous delivery cycle by dividing them into phase-wise testing such as integration level, security, and compliance, system-level testing, etc.
6. Testing Parameter Combinations
Since APIs are the communication channels between application modules, passing parameters and assigning data values to parameters occur through data requests. To detect problems to specific configurations in APIs, teams have to test all possible parameter request combinations. This process becomes complex in larger projects where assigning two different values to the same parameters usually occurs. So, adding extra parameters increases the overall number of possible combinations.
Solution: Testing teams can solve this problem by selecting applications that are critical to daily operations. They have to choose apps to utilize the API and keep release limited just to those apps. This is one of the ways you can see how an API is being used and check for the scopes for any configurational changes to be made for the general availability(GA) release.
7. Validating of Parameters
Validating parameters can be a daunting task for larger projects. Testing teams must validate parameters sent via API requests and ensure that the parameter data uses the correct data type, fits within a designated value range, and passes other validation criteria. For example, the user name is limited to a minimum of 10 characters, and if the user enters less than 10 characters, the API should return a validation failure error.
Solution:
Practicing validation of parameters at the starting of API code can avoid this problem. Plus, you can also detect the problem early on with the help of continuous synthetic API monitoring and get a holistic view by combining it with an APM solution. This checkup will ensure tracking the overall application’s performance by checking API interactions.
8. System Integration
This is to ensure that the API system works as expected with the data tracking system. This also monitors API performance passively by validating all responses of an API call. Since this comes later in the testing process, the team might find it exhausting to implement it.
Solution: To effectively focus on this testing, focus on the applications integrated with other systems in the design phase. Also, avoid testing critical integrations systems in parallel since different apps have different requirements.
Conclusion
Considering these challenges while testing APIs can comprehend your best practices to implement it and prevent hurdles that save time-to-market of your application being increased due to these issues. If you need help establishing a process that overcomes API testing challenges, extend your tech team with experienced testing teams with competency in automation testing and are skilled in API testing. If you have experienced any of the above challenges during the API testing process, comment on your experience or mention any additional challenges you might have faced in API testing.
Author Bio –
Hardik Shah is a Tech Consultant at Simform, a leading custom software development company. He leads large-scale mobility programs that cover platforms, solutions, governance, standardization, and best practices. Connect with him to discuss the best practices of software methodologies @hsshah_