Reproducible Functional Tests for Multi-scale Network Services

Network functions virtualization (NFV) is developed to take advantage of virtualization technologies to separate network functions from the underlying hardware appliances. This approach brings a new level of flexibility in network services deployment for rapid composition, migration and scaling based on changing traffic load and current demand, leading to a higher QoS. Moreover, it allows introducing DevOps approach in the development process resulting in reduced life-cycle and shorter time-to-market. However, in order to realize the anticipated benefits of NFV, developers and network operators need mechanisms to adequately test Virtualized Network Functions (VNF) against different deployment scenarios and in different scales. To this end, we introduce a new library for light-weight automated functional testing of VNFs. It helps the developers to write functional tests in Python and run them on different platforms. Using the library, test developers choose which infrastructure to use, which network services and test VNFs to launch, how to interconnect them, how to trigger the test process and inspect, verify and validate the output against the expected values and conditions. Test developers can use network service packages to deploy services or can compose them in a test code using different parameters to simulate various deployment scenarios. Finally, the library can be used to set automated testing in CI/CD environments or can be used locally during the development phase. In this paper, we describe the architecture of the library, the basic workflow and give an example of testing multiple flavors of a network service using the same code.