Suominen Tero. Performance testing REST APIs

Degree Programme in Computer Science. — SAMK, 2017. — 39 p.The subject for this thesis was performance testing REST APIs that had been implemented into a Java application. The purpose of this research was to come up with a method on how the performance and functionality of the REST APIs could be measured and tested within Profit Software.
The research consisted of two parts. First, I searched to find an existing software capable of being used for testing REST APIs. After selecting the tool that would be used to create the performance tests, a local test environment was set up that allowed us to estimate the capability of the software and the method of testing itself. The local environment consisted of the same components and software that could be used also in the already existing test environments within the company. This way moving the tests from the local environment into the actual test environment went smoothly.
With the help of this research we were able to detect issues with the functionality of some APIs, when they were under load. We were able to fix these issues in the implementation during the development phase and after changing the implementation we could verify that the APIs functioned correctly by using these same tests.