Lars Frantzen

Test generation based on symbolic specifications

Classical state-oriented testing approaches are based on simple machine models such as Labelled Transition Systems (LTSs), in which data is represented by concrete values. To implement these theories, data types which have infinite universes have to be cut down to finite variants, which are subsequently enumerated to fit in the model. This leads to an explosion of the state space. Moreover, exploiting the syntactical and/or semantical information of the involved data types is non-trivial after enumeration. To overcome these problems, we lift the family of testing relations ioco

Model-Based Generation of Testbeds for Web Services

_\mathcal{F}

Audition of web services for testing conformance to open specified protocols

to the level of Symbolic Transition Systems (STSs). We present an algorithm based on STSs, which generates and executes tests on-the-fly on a given system. It is sound and complete for the ioco

Tools for test case generation

_\mathcal{F}

The PLASTIC Framework and Tools for Testing Service-Oriented Applications

testing relations.

On-The-Fly Model-Based Testing of Web Services with Jambition

A Web Service is commonly not an independent software entity, but plays a role in some business process. Hence, it depends on the services provided by external Web Services, to provide its own service. While developing and testing a Web Service, such external services are not always available, or their usage comes along with unwanted side effects like, e.g., utilization fees or database modifications. We present a model-based approach to generate stubs for Web Services which respect both an extra-functional contract expressed via a Service Level Agreement (SLA), and a functional contract modeled via a state machine. These stubs allow a developer to set up a testbed over the target platform, in which the extra-functional and functional behavior of a Web Service under development can be tested before its publication.

Model-based testing of environmental conformance of components

A Web Service (WS) is a type of component specifically conceived for distributed machine-to-machine interaction. Interoperability between WSs involves both data and messages exchanged and protocols of usage, and is pursued via the establishment of standard specifications to which service providers must conform. In previous work we have envisaged a framework for WS testing. Within this framework, this paper focuses on how the intended protocol of access for a standard service could be specified, and especially on how the conformance of a service instance to this specified protocol can then be tested. We propose to augment the WSDL description with a UML2.0 Protocol State Machine (PSM) diagram. The PSM is intended to express how, and under which conditions, the service provided by a component through its ports and interfaces can be accessed by a client. We then propose to translate the PSM to a Symbolic Transition System, to which existing formal testing theory and tools can be readily applied for conformance evaluation. A simple example illustrates the approach and highlights the peculiar challenges raised by WS conformance testing.

A brief history of A-MOST Special Issue containing selected papers from A-MOST 2008

The preceding parts of this book have mainly dealt with test theory, aimed at improving the practical techniques which are applied by testers to enhance the quality of soft- and hardware systems. Only if these academic results can be efficiently and successfully transferred back to practice, they were worth the effort.

A symbolic framework for model-based testing

The emergence of the Service Oriented Architecture (SOA) is changing the way in which software applications are developed. A service-oriented application consists of the dynamic composition of autonomous services independently developed by different organizations and deployed on heterogenous networks. Therefore, validation of SOA poses several new challenges, without offering any discount for the more traditional testing problems. In this chapter we overview the PLASTIC validation framework in which different techniques can be combined for the verification of both functional and extra-functional properties, spanning over both off-line and on-line testing stages. The former stage concerns development time testing, at which services are exercised in a simulated environment. The latter foresees the monitoring of a service live usage, to dynamically reveal possible deviations from the expected behaviour. Some techniques and tools which fit within the outlined framework are presented.

Towards Model-Based Testing of Web Services

Increasing complexity and massive use of current web services raise multiple issues for achieving adequate service validation while sticking to time-to-market imperatives. For instance: How to automate test case generation and execution for stateful web services? How to realistically simulate web service related operation calls? How to ensure conformance to specifications? The Plastic validation framework tackles some of these issues by providing specific tools for automated model-based functional testing. Based on the Symbolic Transition System model, test cases can be generated and executed on-the-fly. This testing approach was applied for validating the Alarm Dispatcher eHealth service, aimed at providing health attention through mobile devices in B3G networks. In this paper we report how this modeling and testing approach helped to detect failures, support conformance, and reduce drastically the testing effort spent usually in designing test cases, validating test coverage, and executing test cases in traditional testing approaches.