What Is API Testing? Types & Best Practices

API TESTING is a software testing type that validates Application Programming Interfaces . The purpose of API Testing is to check the functionality, reliability, performance, and security of the programming interfaces. In API Testing, instead of using standard user inputs and outputs, you use software to send calls to the API, get output, and note down the system’s response. API tests are very different from GUI Tests and won’t concentrate on the look and feel of an application.

This article will examine the importance of REST APIs and REST API testing, practices, and challenges. We will use NASA’s APIs as an example — not just because we LOVE science but since it is also publicly available. TheNear-Earth Object Web Service, which is a RESTful web service for near-earth Asteroid information, allows users to search for Asteroids based on their closest approach date to Earth. You have two unit-testing scenarios, namely the unit-testing of the business logic, and the unit-testing of the REST layer.

Learn How to Secure Your REST APIs

These parameters pass needed information to the API to enable it to perform its function and therefore are necessary for determining whether the API performs as expected. For example, a REST API can accept header, query, and rest body parameters, among other input parameter types. It is very important to maintain the https://globalcloudteam.com/ integrity of the API. In Svitla Systems we always recommend test methods and tools for testing REST API. As a result, lots of time and resources are saved when debugging projects and introducing new features. Load testing – Validating functionality and performance under load, often by reusing functional test cases.

Below are three core objectives of API functional testing. Creating an excellent UI is not possible without an Application Program Interface – the intermediary that bridges gaps between programs. One type of API called Representational State Transfer API can transform businesses of any size or industry by addressing the needs of both companies and consumers. Read on to learn how to use REST API to achieve new heights. The ObjectMapper will convert an appointment to JSON, in order to send it in the POST payload. To use an object will help to reduce the number of columns in the rows of the data driven table.

Why do we need API Security testing?

Forcibly inputting massive amounts of random data, it tests whether the API will stand it or end up with negative behavior like a forced crash or overflow. That’s why the service offers automatic test generation by integrating with a user or organization’s existing APIs on RapidAPI. API monitoring is the process of observing the functional, availability, and performance metrics of an API. The API could be an internal, external, or third-party API that is relied on by another application. Once the testing process is completed, you can get the result of those tests every day.

Validation tests are run late in the testing stage to verify the behavior and efficiency of the API. He has experience working at private and government institutions. Altay discovered his interest for emerging tech after seeing its wide use of area in several sectors and acknowledging its importance for the future. He has background in international political economy, multilateral organizations, development cooperation, global politics, and data analysis. In the “Get text” step details, we will add a validation by clicking the (+) button. We will also add a parameter for the Response field, in order to store the retrieved value .

• Testers can access the full application functionality even before the GUI is implemented.
• In this stage the testers will start designing their test cases which they will combine into test suites.
• In this scenario, the API elevated the customer experience by making the login process convenient and seamless.
• When automated, API testing can be easily performed on a regular basis.
• Focused on communication between APIs, it ensures they are well-connected and don’t cause bugs in other APIs.

REST- representational state transfer, is an architectural technique and a way of communication used to develop web services. It is a logical choice to build APIs and allows users to connect and use cloud-based services with efficacy. API is a collection of programming instructions to access a web-based application. That is, its is a set of commands that a program uses to interact with and use one another’s functions to gather information. The tool is praised for ease of use and speed, tons of features, and many integrations.

There are many types of API tests, from UI to security and validation testing. In most cases, these tests fall under the performance category because they aim to determine the effectiveness of certain aspects of the site. They help organizations collect performance data to improve customer experience. SoapUI is an open-source Java-based API testing tool by SmartBear for functional, security, load, and interoperability testing of SOAP, REST, GraphQL, and JMS web services. JMeter’s pluggable timers allow for simulating various types of loads. Its plugins add extensibility and customization, while built-in functions enable dynamic inputs to a test.

By releasing different APIs for specific functionalities, companies like Twitter, Facebook, LinkedIn and Google have allowed outside world to use and enhance them. This helps these companies reach to a variety of platforms and new markets/users. On the other hand, this allows numerous third-party users to leverage these features for making their own product.

End-to-end testing

You have now learned all the necessary information to do your own REST API testing. You only need to configure the “Patterns to Test” field, like below, according to the response you want to test. Our RESTful API in this blog post is so simple that we do not need to send headers, and you can skip this step. Ordering the API calls based on the sequence function is to be executed. PUT − This method is used to update an entity or create a new one. A representational state transfer API is a type of API that adheres to REST limitations and allows interactions with other sites.

From protecting users from malicious code to maximizing time efficiency, this tool can transform your UI. Usability tests, also called user experience api testing best practices tests, measure the user-friendliness of a software. Experts run them to determine and fix defects that hinder seamless consumer operations.

This is especially true for applications that are widely used and have many applications dependent on them. Database and server should be configured as per the application requirements. Hence, Setting up a testing environment for API automation testing seems a little complex.

How to get started with API testing

Instead of standard user input, we use software to send calls, obtain output and record the response. Whereas unit tests help developers ensure that individual endpoints are working as expected, end-to-end tests are used to validate key user journeys that may involve multiple endpoints and APIs. End-to-end API testing involves chaining requests together and confirming that each one is working properly, which helps teams surface issues in complex workflows before users do.

An integration test combines individual units of work and tests them as a group. It could be testing that when a user accesses a path with the ID of a product, the product details are returned as JSON. Since APIs lack a GUI, API testing is performed at the message layer. API testing is critical for automating testing because APIs now serve as the primary interface to application logic. This is also because GUI tests are difficult to maintain with the short release cycles and frequent changes commonly used with Agile software development and DevOps. Many companies are using microservices for their software applications because they allow software to be deployed more efficiently.

It’s a vast, complex field, making it crucial to know what you want to test. This step is essential to avoid getting overwhelmed with all the available information. Provides information on individual test scenarios and cases.

Automation testing of API needs an app that can interact through an API. Two major types of software testing that can sometimes be confused are API testing and GUI testing. While they are both testing interfaces, the different processes relate to the two interface types we mentioned at the beginning. API testing is a testing method of verifying that the web API responds to requests from the client applications in the correct way.

We provide robust APIs, sample code, and open source projects. They are a chance to learn more about us, our products, and how to level up your skills with our tools. Review the specific requirements needed to run our applications. The ability to see the request and response bodies in a variety of formats, including JSON and XML. The best tools offer automated formatters to make the data easier to enter and view. This feature, in particular distinguishes a true SOAP solution from merely a SOAP client library.

Why is API testing important in an API-first world?

In Kotlintest, you provide a table with data to be tested and the expected results as well (variables starting with ‘exp’ below). But, it requires specific tools, dedicated to automating it. Among other things, those instruments vary in the programming language they’re based on. Following the pattern of the testing pyramid, the first is the unit test layer – code testing often performed by developers while writing it.

Challenges of API Testing

Our tools integrate with over 50 different applications to help you work smarter and faster. Browse our guides and manuals for all our products and addons. However, this is called “breaking compatibility” and means that all clients of the API will need to be updated. Sometimes this option is necessary but it should be avoided if possible.

Also, if an API breaks because errors weren’t detected, there is the threat of not only breaking a single application, but an entire chain of business processes hinged to it. A unit test verifies a small portion of your code independently from other modules of your application. If you’re not writing a “Hello World” app, usually your app will contain services and modules that are interconnected.

The aim is to maximise confidence before the API takes off. Choosing among the tools we described, keep in mind that some of them are better for writing an automation framework , while other tools can be utilized as they are. Designed primarily for UI testing, Katalon is also an integrated environment meant to easily generate and execute API tests. API Virtualization Module starts at €1,131 (around $1,192). It allows you to virtualize critical APIs to reduce dependencies and delays throughout the delivery cycle. At the same time, the module lacks many testing features.

API testing is one of the areas where automated testing is highly recommended, particularly in the world of DevOps, agile development, and continuous delivery cycles. One thing you could do is build a complete app and later perform a manual functional test by clicking every nook and cranny to confirm that it works as expected. In the end, not only would you end up with a low-quality, buggy application that’s brittle, but the building process would be highly frustrating as well. We can write test scenarios very quickly so we can easily create test cases for a lot of edge cases. We also don’t have to run the tests manually so much and we can include our build pipelines.

Not the answer you’re looking for? Browse other questions tagged unit-testingtesting or ask your own question.

Tools such as curl and Postman are essential and effective tools for supporting such development processes. We made a brief and comprehensive comparison of Postman vs. curl in this article. Postman now implements all the necessary tools for testing complex structures in the REST API, and any service that works with HTTP requests can be fully tested with these tools. Regardless of the complex authorization mechanism, no matter how request parameters are formed, and whatever the format of the requested output, these two tools will cope with the task. The popularity and accessibility of these tools make working with them easy in view of the presence of a huge number of examples.