Agile Performance Testing - Testing Experience

tially desired test script shown in the picture below.
Figure 6 – Final Test Script
4. Final Considerations
During the development of our work, several constraints could
be observed that could affect the full utilization of our approach.
We could also point out several enhancements and studying opportunities
for developing the described approach further and
make it a real alternative to all existing performance testing techniques.
These are some of the constraints and opportunities identified:
• Limited feature model representation possibilities. During
domain analysis performed to support the creation of derivation
models, some details needed to be left out in order to
facilitate an easier and faster understanding of the tool to
create new performance test script instances. On the other
hand, some features like simulating user abandonment for
load tests, multiple threads or multiple virtual users groups,
among others, could not be modelled in a way that would
produce a correct derivation, restricting its use to the manual
customization task performed in the last step of our approach.
Future enhancements on our work may successfully
model these features.
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Biography
• Reuse between applications and test type. During the development
of our research, we detected that the reuse of test
scripts may occur among different types of performance
tests and also among different applications. Regarding performance
test types, our work concluded that different performance,
load or stress test scripts vary mostly with regard
to configuration parameters, but generally present a similar
structure. Besides that, we observed that the test scripts of
different applications share several common elements, allowing
a greater reutilization of element definitions.
• Approach usage with other non-functional test types. We
also identified that the defined approach could also be used
for deriving test scripts for other non-functional requirements,
like security, reliability, etc. With regard to security,
for example, it is possible to apply our approach, even including
Jmeter, to simulate scenarios that involve resources exhaustion
to identify possible security failures related to this
condition.
• Eliminating customizations and adaptations through approach
restructuring. A research extension with the purpose
of identifying alternatives is to look into possibilities to make
it possible to eliminate the task of adapting the generated
script for correct execution. This would contribute for the
removal of the recording operation for transactions that are
not included in the derivation tool, which would make the
script generation a lot easier.
• Automatic model derivation through test scripts. This is
about defining a way of adapting the existing annotations
feature, already used by GenArch, to enable an automatic
model derivation from a group of test scripts. This could reduce
the amount of work that currently needs to be done in
script analysis and model creation, which in our research
were done entirely manually.
In our work we defined an approach for the derivation of performance
test scripts for web applications, which is composed of six
steps. This has the main goal of deriving new test script instances,
but also has the objective to allow an easy way of adapting these
test scripts to other test types and scenarios.
In this article, the approach developed during a software engineering
master course accomplished at C.E.S.A.R.(Recife Center for
Advanced Studies and Systems) institute was described in some
detail. For further information regarding the results achieved
and/or any other questions, please contact one of the authors.
José Carréra, MSc, has been test engineer at C.E.S.A.R. (Recife Center
for Advanced Studies and Systems) since 2006 and Professor of
Computer Science at the Faculdade de Tecnologia de Pernambuco,
Brazil, since 2010. He holds a master degree in software engineering,
graduated in computer science, and he is a Certified Tester — Foundation
Level (CTFL), certified through the ISTQB (International Software
Testing Qualifications Board). His research interests include
performance testing, exploratory testing, agile methodologies and
software quality in general.
Uirá Kulesza is an Associate Professor at the Computer Science
Department (DIMAp), Federal University of Rio Grande do Norte
(UFRN), Brazil. He obtained his PhD in Computer Science at PUC-Rio -
Brazil (2007), in cooperation with University of Waterloo and Lancaster University. His main research interests include: aspect-oriented
development, software product lines, and design/implementation of model-driven generative tools. He has co-authored over 70
referred papers in international conferences, journals and books. He worked as a research member of the AMPLE project (2007-2009)
- Aspect-Oriented Model-Driven Product Line Engineering (www.ample-project.net).
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