Right Python Framework Selection for Automation Testing

By Swasti Shrivastava, Softnautics

Test automation is the practice of automating test execution using frameworks and tools to carry out tests more quickly and reduce the need for human testers. In this method of software testing, reusable test scripts are created to test the functioning of the application, cutting down on overall regression time and facilitating quicker software releases. Utilizing test automation shortens the testing life cycle's regression time and improves quality of releases.

According to a report published by future market insights group, the global automation testing market is expected to grow at a CAGR of 14.3% registering a market value of US$ 93.6 billion by the end of 2032. Automated test scripts can be written in several different programming languages, such as Python, C#, Ruby, Java, etc. Among them, Python is by far the most popular language used among automation engineers for automation testing. It provides various useful tools and libraries used for automation testing. Python also extensively supports many different types of test automation frameworks.

Apart from the default Python testing framework, unit test (or PyUnit), various python frameworks are available that can be more suitable for the project. The most appropriate test framework for the project can be selected based on the project requirement, size, and the automation framework practiced, for example, TDD (Test Driven Development), BDD (Behaviour Driven Development), ATDD (Acceptance Test Driven Development), KDD (Keyword Driven Development), etc.

Types of Python testing frameworks

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Test Automation Framework

PyTest:

PyTest is an open-source framework, and it supports unit testing, API testing, and functional testing. In PyTest, the test cases follow a particular format where tests either start with test_ or end with _test.

Prerequisites:

• Basic knowledge of Test-Driven Development framework
• Working knowledge of Python

Pros:

• Can be used for projects that practice TDD
• Helps in writing test suits in a compact manner
• Fixtures and parameterized tests cover numerous test case combinations without rewriting them
• Markers can be used to group tests or skip them when running the entire test suite
• Many inbuilt and third-party plugin support that can add new features like report generation etc.
• Supports parallel execution of test cases using the pytest-xdist plugin
• Huge community support
• Implements python decorators and can leverage python programming flexibility completely

Cons:

• It is not compatible with other python frameworks. All the tests must be rewritten if someone wants to move to another python framework.
• It is purely based on python programming which requires to have sound knowledge over python programming

Robot

The Robot is an open-source framework. It is widely used for Selenium Test Automation.

Prerequisites:

• Basic knowledge of Keyword Driven Development framework
• Working knowledge of python is required to create new keywords

Pros:

• Can be used for projects that practice ATDD, BDD, or keyword driven development
• No prior programming knowledge is required if using pre-defined keywords
• Easy to understand for clients and higher management who are from a non-technical background.
• Many libraries and inbuilt keywords, especially for selenium testing
• Good built-in reporting mechanism
• Good community support

Cons:

• Hard to customize HTML Reports
• No built-in feature for parallel test execution. Pabot can be used to execute test cases parallelly
• Creating new keywords can be time-taking or can be a restriction to testers with coding knowledge and therefore less flexible

Behave

Behave is an open-source framework. It is best suited for web testing. The scripts or feature files syntax is very close to the layman English language.

Prerequisites:

• Basic knowledge of Behaviour Driven Development framework
• Working knowledge of Python

Pros:

• Can be used for projects that practice BDD
• Availability of environmental functions, configuration settings, fixtures, etc. enables easy setup and clean-up
• Easy to understand the framework
• Can be integrated with other web development frameworks like flask, etc.
• Simple to add new test cases
• Report generation in JUnit format
• Excellent support for documentation

Cons:

• Parallel execution of test cases is not supported
• Can only be used for black-box testing

• Not suitable for integration testing

PyUnit

PyUnit (Unit Test) is the default testing framework for unit testing that comes with Python. Similar to PyTest, in PyUnit also the test cases follow a particular format where tests either start with test_ or end with _test.

Prerequisites:

• Working knowledge of Python

Pros:

• No additional package installation is required
• Test report generation is faster
• Individual tests can be run just by typing the test name on terminal
• The default output is easy to understand

Cons:

• Using PyUnit for large projects is significantly hampered by the support for too much abstraction and the abundance of boilerplate code

Nose2

Nose2 is the extension to the unit test. Nose2 adds support to the PyUnit framework by providing plugins.

Prerequisites:

Working knowledge of Python

Pros:

• Easy to install
• Have features like fixtures, parameterized tests, etc. like PyTest
• Tests can be executed in parallel with multiple processes by using the (multiprocess) mp plugin
• Lots of plugins can be added with features like reporting, selenium test automation, etc.

Cons:

• Documentation is not extensive

Despite shorter development cycles, automated testing offers several advantages that are essential for producing high-quality applications. It minimizes the possibility of inevitably occurring human mistakes in manual testing procedures. Software quality is improved and the likelihood of defects endangering the delivery timeline is decreased by automated testing.

Author Bio:

Swasti is working as Senior Automation Engineer at Softnautics and has total of 6+ years of experience as Python Automation Test Engineer. In her career, she has worked on IoT projects, QA and Automation projects which requires test framework development and DevOps. She is passionate about learning new skills, debugging challenges and automation to reduce manual efforts. While not working she likes to listen to audiobooks/music/podcasts.

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