Software testing: methods, types of testing and quality gates
„Was soll das Gerede mit der ‚Freigabe‘? Klingonen erstellen für ihre Software keine ‚Freigabe‘.
Wir lassen die Software aus ihrem Käfig, damit sie eine blutige Spur von Designern und Qualitätsprüfern hinter sich herzieht.“
[From: The 11 most common statements made by Klingon software developers]]
Why software testing?
Fortunately, we have no Klingons on the inSyca team! We prefer to check and test our software solutions before we unleash them on mankind – better safe than sorry.
But seriously: in our digital (business) world, software has become an essential part of daily life. Be it enterprise applications or mobile apps and integrated systems – the quality of software plays an important role in the success of companies and the satisfaction of end users.
As a service provider for solutions in areas such as EDI and the integration of systems, applications and data, software testing has always been a high priority for us.
But how do we ensure that the software we develop meets the highest quality standards?
Clearly, software must be carefully and thoroughly tested: during software testing, applications are put through their paces to ensure that they function properly and meet all requirements.
In this blog post, we will take a closer look at the topic of software testing. In particular, we will focus on Test-Driven Development (TDD), various methods, types of testing, and the importance of quality gates.
First things first: the importance of Test Driven Development (TDD)
Unter Test Driven Development (TDD) is a software development paradigm in which tests are written before the actual code The process involves three steps:
- First, a test is created that describes the desired behavior of the function to be developed.
- Then the minimum code necessary to pass the test is written.
- Finally, the code is optimized to make it more readable, efficient and maintainable without changing the functionality.
There are good reasons for Test Driven Development: for one thing, this method requires careful planning and a clear understanding of the requirements before implementation begins. By writing the tests first, we ensure that the code works as intended and that potential errors are detected early.
In addition, TDD improves code quality because the focus is on writing clear, modular and well-structured code. As a result, Test-Driven Development leads to higher productivity and reduces the costs and effort required to correct errors at a later stage.
By the way, it was the American developer and author Kent Beckwho established the test-first approach in software development in the late 1990s.
What software testing methods are there?
Software testing methods include the strategies, processes or environments used to test the quality of software. The two most widespread methods are arguably the Agile and the waterfall model – both approaches differ greatly in their approach.
The waterfall method
The waterfall model is a traditional Software Development Life Cycle (SDLC)model that consists of a linear sequence of phases, with each phase building on the previous one. In the context of software testing, this means that testing is carried out in separate phases after development.
The waterfall model is usually divided into five phases:
- Anforderungsanalyse: Definition und Dokumentation der Anforderungen der Software.
- Systemdesign: Erstellung des Designs für Architektur und Struktur der Software.
- Implementierung: Schreiben des eigentlichen Codes, basierend auf den Spezifikationen aus den vorherigen Phasen.
- Testen: Das Testen erfolgt hierbei nach der Entwicklung; verschieden Testarten kommen zum Einsatz.
- Wartung: Wurden alle Tests bestanden und die Software freigegeben, erfolgt die Wartung inkl. Fehlerbehebung und Aktualisierungen.
Since the waterfall model only allows for software testing at the end of the development process, errors may only be detected and corrected late in the process. This can lead to higher costs and longer development times, especially if errors are only detected in advanced phases.
We therefore recommend this method only for small projects with low complexity and few processes and participants.
Die Agile Methode
As the name suggests, the Agile software testing method is linked to the principles of agile software development. In contrast to the waterfall model, testing in agile development is not carried out in separate phases after development, but is continuously integrated throughout the entire development process.
The main features:
- Kontinuierliche Tests: Tests erfolgen in kurzen Iterationen oder Sprints von ca. ein bis vier wochen Dauer.
- Testgetriebene Entwicklung (TDD): Tests werden vor der Implementierung geschrieben und definieren das erwartete Verhalten der Software, bzw. dienen als Spezifikationen für die Entwicklung.
- Automatisierung von Tests: Fördert einen schnellen Entwicklungszyklus, Tests können effizient und häufig durchgeführt werden.
- Continuous Integration and Deployment (CI/CD): Verwenden von CI/CD-Pipelines, um den Code regelmäßig zu integrieren, zu testen und bereitzustellen -> kontinuierliche Lieferung von Software und schnelle Reaktion auf Änderungen oder Probleme.
- Zusammenarbeit und Kommunikation: Enge Kooperation der Testern mit Entwicklern, Produktmanagern und anderen Teammitgliedern zusammen, um Anforderungen zu verstehen, Tests zu entwerfen und Feedback auszutauschen.
By taking this approach, the Agile testing method ensures faster software delivery, higher quality and flexibility, and better adaptability to changing requirements and customer needs.
The DevOps method
The DevOps model is closely related to the agile approach: the term DevOps is composed of development and operations and describes a method that incorporates both development and operational aspects.
The approach to software testing is basically the same as the Agile method, with continuous testing at sprint intervals, TDD, automation, etc.
However, while Agile focuses on software development itself, DevOps focuses primarily on improving delivery speed and quality by eliminating the separation between development and operations.
Despite, or perhaps because of, the different focuses, the two methods complement each other very well.
We are not only familiar with software testing: as a specialist in the areas of Electronic Data Interchange (EDI) and the integration of systems, applications and data, we offer you expert advice and practical solutions to optimize your business processes for a successful future.
Talk to us to find out more about how we can support you in your project!
Contact us to learn more about how we can make it in your project the support!
What types of software testing are there?
In software testing, there are different types of tests, also known as test procedures, which are used in various areas of software engineering to check the functionality of software. Here, different types of test procedures can be distinguished, including:
Functional testing
The aim of functional software tests or function tests is to check the functional correctness of a software application. Essentially, functional tests are carried out to ensure that the software does what it is supposed to do, and does it in a way that meets the specifications.
This typically involves testing user inputs, executing actions within the application, and checking the results.
The four most common functional tests include:
- Unit testing: : unit testing is the process of testing the individual software modules/components that make up an application. These tests are usually carried out at the smallest level of software development, such as individual methods or functions. The purpose of this type of testing is to ensure that each unit of the software works properly and can be tested independently of other parts of the system.
- Integration tests: in contrast to unit tests, integration tests are used to test the interaction of the various components of an application. Integration tests are usually also referred to as End-to-End Tests (E2E Tests) and can be carried out at different levels, from the integration of classes or modules to the integration of services or systems.
- Systemtests: Mit Systemtests schließlich, wird ein System in seiner Gesamtheit umfassend getestet. Idealerweise haben die betroffenen Software- und auch Hardwarekomponenten vorab bereits Unit-Tests und Integrationstests erfolgreich durchlaufen. Diese Art von Software-Testing orientiert sich an der Black-Box-Testmethode, bei der die Software unter realen Benutzerbedingungen sowie unter besonderen Ausnahmeszenarien überprüft wird.
- Akzeptanztests: Hier steht der Endbenutzer einer Software im Mittelpunkt, bzw. die Benutzerfreundlichkeit einer Anwendung. Diese Tests simulieren typische Benutzerszenarien und überprüfen, ob die Software die Erwartungen der Benutzer erfüllt und z.B. intuitiv zu bedienen ist. Akzeptanztests werden in der Regel nach Abschluss der Entwicklung durch-geführt, um sicherzustellen, dass die Anwendung bereit ist, vom Kunden angenommen und verwendet zu werden.
Non-functional testing
Not only the functionalities of a software should be thoroughly tested, but also non-functional parameters such as performance, security, usability and scalability should be given attention.
With non-functional tests, we determine whether the software meets user expectations and industry standards. Without this type of testing, potential problems such as slow performance, security vulnerabilities or an inadequate user experience could go unnoticed and thus affect the acceptance of the software.
Examples of non-functional tests:
- Leistungstests (Performance Tests): Die Leistung der Software wird geprüft, einschließlich Antwortzeiten, Skalierbarkeit und Belastbarkeit unter verschiedenen Lastbedingungen.
- Sicherheitstests: Die Sicherheit der Software steht hier im Fokus, um sie vor Bedrohungen wie Hackerangriffen, Datenlecks oder unbefugtem Zugriff zu schützen.
- Usability testing: The user-friendliness of the software is evaluated, including the user interface, navigation and general user experience – similar to acceptance testing.
- Kompatibilitätstests: Hier überprüft man, ob die Software auf verschiedenen Plattformen, Betriebssystemen, Browsern oder Gerätetypen ordnungsgemäß funktioniert.
- Zuverlässigkeitstests: Die Zuverlässigkeit der Software wird getestet, einschließlich ihrer Fähigkeit, stabil zu funktionieren und unerwartete Ausfälle zu vermeiden.
- Barrierefreie Tests: Wichtig ist auch, dafür Sorge zu tragen, dass die Software barrierefrei und die Zugänglichkeit für Benutzer mit Behinderungen gewährleistet ist.
Regression testing
Regression testing is used to determine how new changes or updates to a software application affect existing functionality. It is important to perform regression testing to ensure that parts of the software that have already been tested and found to work continue to function properly after a change.
Regression testing can be both functional and non-functional, depending on which aspects of the software are being checked:
- Functional regression testing: this refers to the software's existing functionalities and that it continues to work correctly after a change. This also includes re-running test cases that have already been executed to ensure that no new errors have been introduced.
- Nicht-funktionaler Regressionstest: Überprüfen die Aspekte der Softwarequalität, die nicht unbedingt zu den funktionalen Anforderungen der Software gezählt werden (Performance, Sicherheit, Benutzerfreundlichkeit und Skalierbarkeit). In diesem Fall werden Änderungen an der Software daraufhin überprüft, ob sie die bestehenden nicht-funktionalen Anforderungen erfüllen und keine negativen Auswirkungen auf diese Aspekte haben.
What types of software errors are there?
Nachdem wir uns eingehend mit den verschiedenen Varianten von Software-Testing beschäftigt haben, lohnt sich auch ein Blick auf die diversen Fehlerquellen. Im Zusammenhang mit Softwarefehlern taucht hier gern der Begriff „Bug“ auf – also das englische Wort für Käfer:)
Bugs appeared in the early days of the first computers. At that time, computers still existed as huge calculating machines in which insects could easily get lost and cause errors in the system.
A vivid example is provided by a logbook entry from 1947 – complete with a glued-in bug – when a bug was found in the Mark II Aiken Relay Calculator .
But legend has it, that Thomas Edison is said to have spoken of bugs as early as 1878, when he complained about difficulties with his inventions.
But let's take a closer look at the most common software bugs:
- Logische Fehler: Logikfehler treten immer dann auf, wenn der Code nicht die erwarteten Ergebnisse liefert oder sich nicht wie erwartet verhält. Tricky sind sie auch noch: Sie entstehen oft durch Fehler im Algorithmus oder in der Logik des Programms und können schwer zu finden sein, da sie nicht notwendigerweise zu einem Absturz der Anwendung führen.
- Syntax errors: syntax errors occur when code violates the rules and structures of the programming language. These errors are often detected during compilation and prevent the code from being executed.
- Laufzeitfehler: Zu Laufzeitfehlern kommt es hingegen während der Ausführung des Programms – sie werden nicht während der Kompilierung erkannt. Sie können durch unerwartete Eingaben, fehlende Ressourcen oder unerwartete Bedingungen im Programmablauf verursacht werden und führen häufig zu Programmabstürzen oder unerwartetem Verhalten der Anwendung.
- Schnittstellenfehler: Diese Fehler treten auf, wenn die Kommunikation zwischen verschiedenen Modulen oder Komponenten der Software nicht korrekt funktioniert. Sie führen dazu, dass Daten falsch übertragen oder interpretiert werden und verursachen damit Fehlfunktionen in der Anwendung.
- Leistungsprobleme: Zeigen sich, wenn die Software nicht die erwartete Leistung erbringt, in Form von z. B. lange Ladezeiten, hoher Speicherverbrauch oder schlechte Reaktionszeiten. Diese Probleme können auf ineffizienten Code, unzureichende Ressourcenallokation oder Skalierbarkeitsprobleme zurückzuführen sein.
Software testing and quality gates
What are quality gates?
Quality gates are defined milestones or criteria in the software development process that determine when certain phases are completed or when a production release can be approved.
They serve as important checkpoints to ensure that certain quality standards are met before a project or phase is continued.
The role of quality gates in software testing
- Qualitätskontrolle: Quality Gates sorgen dafür, dass die Software den festgelegten Qualitätsstandards entspricht und die Anforderungen erfüllt.
- Risikomanagement: Potenzielle Risiken lassen sich mit dem Einsatz von Quality Gates frühzeitig identifizieren und adressieren, bevor sie sich zu größeren Problemen entwickeln.
- Entscheidungsfindung: Sie bieten klare Kriterien, um fundierte Entscheidungen darüber zu treffen, ob ein Projekt fortgesetzt oder ein Release freigegeben werden soll.
- Effizienzsteigerung: Durch die Implementierung von Quality Gates können unnötige Kosten und Verzögerungen vermieden werden, da Probleme frühzeitig erkannt und behoben werden können.
- Stakeholder-Kommunikation: Auch in der Kommunikation mit Stakeholdern über den Fortschritt des Projekts und die Qualität der Software, dienen Quality Gates als nützliches Instrument.
As we see, the use of quality gates goes a long way towards improving the quality and reliability of software products so that they meet the requirements of users and the organization.
Conclusion
Software testing will be important in the future because software technologies and requirements are constantly evolving – and the challenges and demands are not diminishing.
With the advent of artificial intelligence, machine learning, the Internet of Things (IoT) and other innovations, software testing challenges are also becoming more complex. It is important that software testing practices and tools keep pace with these developments and evolve to meet growing demands.
Automation, continuous integration and continuous delivery (CI/CD), DevOps practices and Agile testing will keep on playing a major role in increasing the efficiency and speed of software development processes.
In addition, non-functional testing, such as performance, security and usability testing, will become more important to ensure that software not only works smoothly but also meets performance, security and user experience requirements.
It is therefore worth investing in comprehensive software testing: for more quality and reliability in software products and ultimately more success in development projects, both today and in the future.
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