A Web service is the medium of communication through which two application can exchange the data without knowing the underlying architecture. In other words, Web Service is a way to publish your application over the web and allow other applications to access functions defined by your web service. Web Services with high response time and poor performance can annoy users. Hence, Web service load testing helps you in recognizing the performance problems before deploying web service for end users.

Need of Web Service Load Testing

In today’s world, a software application is developed which is consumed by the human beings. One person sends a request in human readable format to the application and gets the response back in human readable format. In the modern era of technology, web application becomes too complex. Therefore if you want to build your own web application then you do not need to build each and everything from scratch. There are a lot of ready-made web services are available which can be plugged into your application. For example, if you want to make a web application for maps then you can use Google Maps API directly without implementing your own. With the help of Web service load testing, you can design and simulate usage traffic. Therefore, you can measure performance, reliability, and scalability of Web Service infrastructure.

Implementation of Web Services

There are mainly two different approaches for implementing the Web Services i.e SOAP and REST.

SOAP (Simple Object Access Protocol)

SOAP is a standard protocol defined by the W3C Standard. It is an XML-based messaging protocol for exchanging information among applications. The messages are exchanged between application within the SOAP envelopes.

REST(Representational state transfer)

REST is not a protocol, it’s a web standard based architecture which uses HTTP protocol for data communication. In REST each and everything is a resource therefore, every resource is identified by a unique URI (Uniform Resouce Identifier) or Global Ids. REST uses various representations to represent a resource like Text, JSON, and XML.

WSDL(Web Services Description Language)

WSDL is an XML document containing information about web services like a method name, method parameter and how to access it. It also defines how the services can be called. WSDL is a part of UDDI. Therefore, it acts as an interface between web service applications.

How to perform Web Service Load Testing

First of all, Web service load testing includes testing the performance and scalability of your Web Services with varying user load. Web service load testing helps you determine how your Web Service behaves when multiple users hit it concurrently. In Web service load testing real-time traffic (user load) is generated for the web service application. There are a lot of ways to perform the web service testing, for example, Using Apache Axis2 API and Using SoapUI. Therefore, I prefer you to take a right tool for the web service load testing like AppPerfect Load Test. It supports load testing for web service using SOAP protocol. You can perform HTTP load testing in it. Along with this, you can parameterize web services with any values. If you want to get more detail about it please click here.