What is Web Services Testing: How to Test and Automate?

What is Web Service Testing?

Web services testing is the testing of data transfer between two servers on the Internet. The process involves validating the web services in testing for functionality, reliability, performance, and security. Like every other test, you can test web services manually or automate web service testing.

What is the Importance of Web Service Testing?

Many online applications today use web services. They function on the request-response principle. Users send a request for data and receive an understandable response from the application.

So, if you want to display the running status of trains in your application, use the already available service in the market, buy it from the people who own it, and embed it within your application. You can call this web service within your software application via SOAP or HTTP protocol. 

A real-life example is Google Maps, which cab service apps such as Uber use. Other examples include financial services platforms, such as Groww and ETMoney, which access stock information from the financial market.

Here are some of the more reasons why web services are essential:

• HTTP requests invoke web services. Once it exposes your code on the network, other applications can use the services you provide within your software.
• Web services allow multiple applications to talk to each other and share data over the network.
• They use a standardized protocol for communication, which offers businesses a wide range of choices, including lower costs and better quality for using existing services.

Different Types of Web Service Testing

• Functional Testing – Test if APIs return the correct functionality, validate HTTP methods, and check response structure.
• Regression Testing – To ensure existing functionalities work after updates or bug fixes, re-run previously passed API tests after code changes and detect breaking changes in endpoints, request/response structures, or business rules.
• Security Testing – Identify vulnerabilities and ensure secure access to services. Validate authentication and check if sensitive data is encrypted in transit. 
• Performance Testing – Simulate multiple users accessing the API and test for its performance under critical conditions.
• Interoperability Testing – Interoperability testing is used to determine whether a SOAP service developed in .NET can be consumed by a Java client. It also checks whether a REST API integrates correctly with a third-party mobile app. 
• Contract Testing – Contract testing is vital in microservices, where breaking the API contract can cause failures downstream. 

Benefits of Web Service Testing

• Ensures Core Functionality – Verifies that each API or service works as intended and returns the correct responses.
• Supports System Integration – Confirms smooth communication between microservices or different platforms.
• Speeds Up Development – Enables early testing before the UI is built, reducing bugs and release delays.
• Enhances Security & Compliance – Detects vulnerabilities like unauthorized access, data leaks, or broken authentication.
• Improves Performance & Scalability – Identifies slow or unstable services under high load conditions.

Challenges in Manual Web Service Testing

• Complex Service Dependencies – Testing services that rely on other APIs or databases can lead to flakiness or false failures.
• Frequent API Changes – Continuous updates in endpoints or request/response formats increase test maintenance.
• Security Testing Complexity – Validating authentication (OAuth, JWT) and handling secure headers or tokens can be tricky.
• Limited UI Visibility – Since web services are backend components, identifying their impact on user experience can be difficult.

Role of Automation in Web Service Testing

Automation plays a significant role in web services testing by turning slow and repetitive processes into fast, scalable, and intelligent workflows. Instead of manually checking every API endpoint or response, web service automation lets QA teams run hundreds of test cases in seconds, around the clock, and across environments. It integrates seamlessly into CI/CD pipelines, catching bugs the moment they appear and ensuring rapid, reliable deployments. 

With modern AI-powered testing tools, automation goes further by auto-generating test cases from API specs, healing broken tests, and prioritizing high-risk scenarios based on past behavior. In short, automation doesn’t just speed things up; it transforms web service tests from a bottleneck into a competitive advantage.

How Can Testsigma Help with Automated Web Service Testing?

With Testsigma, you can automate test cases for REST APIs testing in just a few minutes. All you need to do is enter the endpoint, select the method, add headers, set the status code, and run the test. With our tool, you can:

• Validate different REST API methods (GET, PUT, POST, DELETE, HEAD) separately or in one integrated test to ensure comprehensive test coverage.
• Verify multiple scenarios with various data sets without changing the test script every time.
• Store and reuse API responses by automatically capturing specific run-time data.
• Set up tests automatically as part of your CI/CD pipeline with our native integrations.
• Receive detailed insights into the status of your tests with detailed logs, screenshots, and more.

The image shows the REST API methods (GET, PUT, POST, DELETE, PATCH) that can be tested using Testsigma.

Testsigma is a codeless Agentic AI-driven test automation platform that offers multiple benefits to testers. You can test web service that include all REST APIs, such as GET, POST, PUT, PATCH, and DELETE. You can understand more about the features of automated API testing with Testsigma here.

Frequently Asked Questions