8 Best Practices in API Automation Testing

Application Programming Interfaces (APIs) help software development teams to easily connect and engage in end-to-end business processes. APIs are the key to web apps & services. However, these end-to-end processes can only be as high-performing as the APIs they depend on.

Building automated tests for API and QA pipelines for web services is tough. Of the most prominent issues automated end-to-end API Functional Testing and acceptance testing techniques face are:

I. Unreliable and flaky tests

II. Hard to isolate and identify large systems errors

III. Slow turnaround time for bug fixes

IV. Setup and tear down steps can leave leftover test data which can alter future tests and production systems.

To overcome these issues, here are a few must-follow API Test Automation practices when it comes to testing Application Programming Interfaces upfront:

1- Do Not Repeat Yourself

Before adding tests, make sure to create a client for your system under test.

Avoid repeating the code, but many tests require addressing the same components or similar actions. In such cases, you might want to create a common library to wrap the test requests and make their usage shorter and the process as simpler as possible.

2- Clarity

Write clear tests that easily allow debugging.

When tests are running successfully, they hardly require any attention or time. When the same tests start failing, resources need to be allocated to find the cause of failure. This process is time-consuming during product development and can go as far as pushing deadlines or cutting new features from your product in place.

Here are a few reasons your tests fail –

  • Flaw and instability in automated test
  • Environment failure or environment limitation
  • Changes to the product without marking changes to test
  • Flaw and instability in functionality

To save resources and optimize the process as much as possible, debugging should be a priority while you create the test.

  • Each ‘System under Test’ component need to be tested separately for each possible configuration.
  • All the additional information like descriptors, ids; should be included in the report to make it more informative.
  • Any failure of the test should be clear in the report. Moreover, the results of any failure must be saved and accessible in the system so that data can be traced back.

3- Performance

Always keep tabs on API performance functionality using API tests. These tests can be set up to monitor availability and speed issues, and the data collected over time can be used to analyze the performance trends.

Although testing just the availability is not enough, most API transactions involve data exchange, so it becomes quite necessary to ensure that the data is reliable. You can also test if the APIs are functioning correctly by validating the inputs and ensuring their data is structured in the correct format.

Test functionality of new deployments to catch issues before real-time users are impacted -when rolling out new features as part of a release, it is important to measure the impact on existing API integrations. The application might slow down drastically or at times even crash if the changes in the application do not work with the APIs you use.

Continuously testing API endpoints to ensure availability – monitoring API endpoints help you to identify outages or performance issues quickly. This minimizes the impact on end-users.

Test all of the application API dependencies to make sure performance is not degraded. When you have multiple APIs built into an application or provide APIs that integrate with applications using multiple APIs, it is recommended that you test the API dependencies frequently since they are constantly upgraded and updated.

4- Treat the API you’re Testing Like a Consumer Would

If you’re testing an API, you need to treat it exactly as a consumer would. At times, while writing test suites we focus too much on what we know to be the proper response. To properly examine all our API endpoints, we need to introduce the sort of errors that a user might introduce knowingly or unknowingly. In other words, we need to think like a user. After all, things rarely break in predictable ways in a live environment so it’s really important to test like we’re already there.

5- Eliminate as Many Fixed Data Sources as Possible

API endpoints often rely on the output from other APIs, when in a live environment. The only way to ensure that this is intact is to create an integration test which calls the first API and then uses the result of that call to hit the second API. When we begin testing the second API with collected static expected data from the first API, we are no longer testing the environment holistically. We should follow actual user flows and create integration tests rather than testing individual endpoints in thin air, wherever possible.

6- Other Factors That Need To Be Taken Care Of

A tester must have –

Parameters:

  • List of all required parameters in JSON request
  • List of all mandatory params in JSON request

Connections:

When it comes to Performance testing you need to check-

a) The number of concurrent connections a server can take before it fails.
b) Concurrent loads in batches like 25, 100, 200, and 500.
c) The expected response time and the expected throughput for all user loads.
d) The expected queries executed per second

7- Structuring tests

An API consists of several methods and operations which can be tested individually as well as through a setup of test scenarios. These test scenarios are usually constructed by combining multiple API calls.

Here are some approaches to test any API:

  • Perform syntax testing of individual methods and operations wherever possible

This is performed to check whether a method or operation accepts correct input and rejects incorrect input. For instance:

I. Syntax testing determines if leaving mandatory fields empty results in an error

II. Optional fields are easily accepted as expected

III. Filling fields with incorrect data types should result in an error

  • Perform functional testing of individual methods and operations wherever possible

This type of testing is performed to check whether the method and operations perform their intended action correctly. For instance:

I. Check whether calculation A is performed correctly when calling operation or method B with parameters X, Y, and Z.

II. Check whether data is stored correctly for future use when calling a setter method.

III. Check whether calling a getter method retrieves the correct required information.

  • Construct and execute a decent amount of test scenarios

When individual methods and operations have been tested successfully, method calls can be bound together to emulate business processes.

8- API virtualization

When testing systems of interconnected components, some of the availability of the components required for testing might be limited at the time of testing. Reasons for this might be:

I. The component itself is not developed yet

II. The component holds insufficient or unusable test data

III. The component is shared with other teams and hence cannot be freely used

In any of the above cases, virtualization of the API can be a valuable solution, enabling testing to continue as planned. API virtualization can be achieved through:

  • Stubbing – This is used to create an emulation of an API, mostly used for SOAP and REST web services.
  • Virtualization – This enables the simulation of the behavior of complex components, including back-end database connectivity and transport protocols other than HTTP.
  • Mocking – This is done for code objects using a framework such as Mockito.

Hence, if you’re planning to test applications in an agile environment, make sure you follow all the best API Test Automation practices mentioned here.

6 Reasons Why Manual Testing Won’t Replace Automated Testing

There are so many discussions that automation testing is replacing manual testing. A lot of developers & testers in modern era want to look for the help of automation testing to make their lives simple. Test automation has received interest and much attention in recent times. But, the truth is that you can’t expect automation testing to execute all the work done by a software tester. A lot of developers and testers in the modern era prefer to seek the assistance of test automation to make their testing easy. However, test automation doesn’t have the capability to completely replace manual software testing. Therefore, we cannot expect that automation testing is stealing the job of software testers out there in the software testing world.

Reasons Why Test Automation will never replace Manual Testing:

  • It only tests what is predictable- Automated tests assure people that what we anticipate to happen does, in fact, turn out. We name this the “happy path”. Automation testing concentrates on functionality that already exists. It isn’t deep but its coverage is enormous. Test Automated is effective for regression tests, precisely when resources are restricted. But only doing test automation is sure to introduce some drawbacks and disappointment in your software testing process.
  • Automation is excessively expensive for small testing projects- Not just do you have automation testing software to pay for, but you also have high maintenance and management related costs, because of script writing & rewriting, including arrangement, set up and processing times. For big and long term projects, the higher expenses can be worth it. But for small and short projects it’s a massive waste of both money and time. When estimating the potential ROI for an automation purchase, you have to factor in additional man hours, too.
  • Automating usability tests is just impossible- Usability testing cannot be automated and it necessitates a human. You cannot train a system (laptop, computer, etc.) to spot “good” usability vs. “bad” usability. Perhaps you might think like, “Ok, we can easily skip usability testing”. Do not make such type of mistake. By skipping this type of testing, you are introducing an incredible amount of threat. This step in the Quality Assurance process is vital to ensure confidence in the product release. There is no means around involving manual testers in usability testing.
  • Automation Testing can contain faults/ bugs- Just like your app’s code can have bugs, automated tests can too. Automation tests can also catch Issues that are unaware of. If you write tests with bugs, you are literally going to have false positives, which can lead to several threats and problems for your clientele and your team. The human element of manual testing can spot these errors and ensure you are testing appropriately.
  • In agile, testing scripts have to be rewritten – Working with continuous feedback in agile environs means fluid changes to the flow of the product, the User Interface, or even attributes. And nearly every time, a modification entails a rewrite of the automated scripts for the subsequent sprint. Fresh new modifications also affect the testing scripts for regression tests, so even that classic automation example necessitates a lot of updates in agile.
  • Technical limits can come into play- The number of test scenarios is complex or downright impossible to automate. The universal argument is “automated testing is cheap”. But it’s not challenging to spend a ton of money and time on elaborate automation. For instance, testing a series of touch screen devices. How do you automate the understanding of a “swipe“and a “tap”. You cannot do that in a way that is equivalent to human being usage.

Final Verdict

The existence of both automated testing and manual testing forces us to think about our option of tools, their charge, and the rewards they will provide. There are a place and time for both testing techniques. Manual testing helps us understand the complete problem and explore other tests angles with flexibility. Test automation helps save time in the long run by achieving a large number of surface level tests in a limited time. It is up to you to decide where and when every single method of testing is used. Even though automation would not replace forms of manual testing, yet neither will manual testing remove automation. Once the distinction between them is understood, the in-depth dread of automation breaks down and a competent, gainful coordinated attempt rises.

We at ImpactQA provides both Quality Assurance manual testing as well as Automation using all the most recent automation testing and manual testing tools.