In
software testing, test automation is the use of
software separate from the software being tested to control the execution of tests and the comparison of actual outcomes with predicted outcomes. Test automation can automate some repetitive but necessary tasks in a formalized testing process already in place, or perform additional testing that would be difficult to do manually. Test automation is critical for
continuous delivery and
continuous testing.
There are many approaches to test automation, however below are the general approaches used widely:
*
Graphical user interface testing. A testing framework that generates
user interface events such as keystrokes and mouse clicks, and observes the changes that result in the user interface, to validate that the observable behavior of the program is correct.
*
API driven testing. A testing framework that uses a programming interface to the application to validate the behaviour under test. Typically API driven testing bypasses application user interface altogether. It can also be testing
public (usually) interfaces to classes, modules or libraries are tested with a variety of input arguments to validate that the results that are returned are correct.
One way to generate test cases automatically is
model-based testing
Model-based testing is an application of model-based design for designing and optionally also executing artifacts to perform software testing or system testing. Models can be used to represent the desired behavior of a system under test (SUT), or ...
through use of a model of the system for test case generation, but research continues into a variety of alternative methodologies for doing so. In some cases, the model-based approach enables non-technical users to create automated business test cases in plain English so that no programming of any kind is needed in order to configure them for multiple operating systems, browsers, and smart devices.
What to automate, when to automate, or even whether one really needs automation are crucial decisions which the testing (or development) team must make. A multi-vocal literature review of 52 practitioner and 26 academic sources found that five main factors to consider in test automation decision are: 1) System Under Test (SUT), 2) the types and numbers of tests, 3) test-tool, 4) human and organizational topics, and 5) cross-cutting factors. The most frequent individual factors identified in the study were: need for regression testing, economic factors, and maturity of SUT.
A growing trend in software development is the use of
unit testing frameworks such as the
xUnit frameworks (for example,
JUnit and
NUnit) that allow the execution of unit tests to determine whether various sections of the
code
In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communication ...
are acting as expected under various circumstances.
Test cases describe tests that need to be run on the program to verify that the program runs as expected.
Test automation, mostly using unit testing, is a key feature of
extreme programming and
agile software development
In software development, agile (sometimes written Agile) practices include requirements discovery and solutions improvement through the collaborative effort of self-organizing and cross-functional teams with their customer(s)/ end user(s), ad ...
, where it is known as
test-driven development (TDD) or test-first development. Unit tests can be written to define the functionality ''before'' the code is written. However, these unit tests evolve and are extended as coding progresses, issues are discovered and the code is subjected to refactoring.
Only when all the tests for all the demanded features pass is the code considered complete. Proponents argue that it produces software that is both more reliable and less costly than code that is tested by manual exploration. It is considered more reliable because the code coverage is better, and because it is run constantly during development rather than once at the end of a
waterfall development cycle. The developer discovers defects immediately upon making a change, when it is least expensive to fix. Finally,
code refactoring
In computer programming and software design, code refactoring is the process of restructuring existing computer code—changing the '' factoring''—without changing its external behavior. Refactoring is intended to improve the design, structur ...
is safer when unit testing is used; transforming the code into a simpler form with less
code duplication, but equivalent behavior, is much less likely to introduce new defects when the refactored code is covered by unit tests.
Some
software testing tasks (such as extensive low-level interface
regression testing) can be laborious and time-consuming to do manually. In addition, a manual approach might not always be effective in finding certain classes of defects. Test automation offers a possibility to perform these types of testing effectively.
Once automated tests have been developed, they can be run quickly and repeatedly. Many times, this can be a cost-effective method for regression testing of software products that have a long maintenance life. Even minor patches over the lifetime of the application can cause existing features to break which were working at an earlier point in time.
While the reusability of automated tests is valued by software development companies, this property can also be viewed as a disadvantage. It leads to the so-called
"Pesticide Paradox", where repeatedly executed scripts stop detecting errors that go beyond their frameworks. In such cases,
manual testing
:''Compare with Test automation''.
Manual testing is the process of manually testing software for defects. It requires a tester to play the role of an end user where by they use most of the application's features to ensure correct behaviour. To ...
may be a better investment. This ambiguity once again leads to the conclusion that the decision on test automation should be made individually, keeping in mind project requirements and peculiarities.
Test automation tools can be expensive and are usually employed in combination with manual testing. Test automation can be made cost-effective in the long term, especially when used repeatedly in
regression testing. A good candidate for test automation is a test case for common flow of an application, as it is required to be executed (regression testing) every time an enhancement is made in the application. Test automation reduces the effort associated with manual testing. Manual effort is needed to develop and maintain automated checks, as well as reviewing test results.
In automated testing, the test engineer or
software quality assurance person must have software coding ability since the test cases are written in the form of source code which when run produce output according to the
assertions that are a part of it. Some test automation tools allow for test authoring to be done by keywords instead of coding, which do not require programming.
API testing
API testing
API testing is a type of software testing that involves testing application programming interfaces (APIs) directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security. ...
is also being widely used by software testers as it enables them to verify requirements independent of their GUI implementation, commonly to test them earlier in development, and to make sure the test itself adheres to clean code principles, especially the single responsibility principle. It involves directly testing
APIs as part of
integration testing
Integration testing (sometimes called integration and testing, abbreviated I&T) is the phase in software testing in which individual software modules are combined and tested as a group. Integration testing is conducted to evaluate the complianc ...
, to determine if they meet expectations for functionality, reliability, performance, and security.
[Testing APIs protects applications and reputations](_blank)
by Amy Reichert, SearchSoftwareQuality March 2015 Since APIs lack a
GUI
The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, inste ...
, API testing is performed at the
message layer.
[All About API Testing: An Interview with Jonathan Cooper](_blank)
by Cameron Philipp-Edmonds, Stickyminds August 19, 2014 API testing is considered critical when an API serves as the primary interface to
application logic In computer software, business logic or domain logic is the part of the program that encodes the real-world business rules that determine how data can be created, stored, and changed. It is contrasted with the remainder of the software that might ...
.
Continuous testing
Continuous testing is the process of executing automated tests as part of the software delivery pipeline to obtain immediate feedback on the business risks associated with a software release candidate.
[Part of the Pipeline: Why Continuous Testing Is Essential](_blank)
by Adam Auerbach, TechWell Insights August 2015[The Relationship between Risk and Continuous Testing: An Interview with Wayne Ariola](_blank)
by Cameron Philipp-Edmonds, Stickyminds December 2015 For Continuous Testing, the scope of testing extends from validating bottom-up requirements or user stories to assessing the system requirements associated with overarching business goals.
[DevOps: Are You Pushing Bugs to Clients Faster](_blank)
by Wayne Ariola and Cynthia Dunlop, PNSQC October 2015
Graphical User Interface (GUI) testing
Many test automation tools provide record and playback features that allow users to interactively record user actions and replay them back any number of times, comparing actual results to those expected. The advantage of this approach is that it requires little or no
software development
Software development is the process of conceiving, specifying, designing, programming, documenting, testing, and bug fixing involved in creating and maintaining applications, frameworks, or other software components. Software development invol ...
. This approach can be applied to any application that has a
graphical user interface. However, reliance on these features poses major reliability and maintainability problems. Relabelling a button or moving it to another part of the window may require the test to be re-recorded. Record and playback also often adds irrelevant activities or incorrectly records some activities.
A variation on this type of tool is for testing of web sites. Here, the "interface" is the web page. However, such a framework utilizes entirely different techniques because it is rendering
HTML and listening to
DOM Events instead of operating system events.
Headless browser
A headless browser is a web browser without a graphical user interface.
Headless browsers provide automated control of a web page in an environment similar to popular web browsers, but they are executed via a command-line interface or using netwo ...
s or solutions based on
Selenium Web Driver are normally used for this purpose.
[Headless Testing with PhantomJS;http://phantomjs.org/headless-testing.html]
Another variation of this type of test automation tool is for testing mobile applications. This is very useful given the number of different sizes, resolutions, and operating systems used on mobile phones. For this variation, a framework is used in order to instantiate actions on the mobile device and to gather results of the actions.
Another variation is script-less test automation that does not use record and playback, but instead builds a model of the application and then enables the tester to create test cases by simply inserting test parameters and conditions, which requires no scripting skills.
Testing at different levels

A strategy to decide the amount of tests to automate is the test automation pyramid. This strategy suggests to write three types of tests with different granularity. The higher the level, less is the amount of tests to write.
Levels
* As a solid foundation,
Unit testing provides robustness to the software products. Testing individual parts of the code makes it easy to write and run the tests. Developers write Unit Tests as a part of each story and integrate them with CI.
* The service layer refers to testing the services of an application separately from its user interface, these services are anything that the application does in response to some input or set of inputs.
* At the top level we have
UI testing which has fewer tests due to the different attributes that make it more complex to run, for example the fragility of the tests, where a small change in the user interface can break a lot of tests and adds maintenance effort.
Framework approach in automation
A test automation framework is an integrated system that sets the rules of automation of a specific product. This system integrates the function libraries, test data sources, object details and various reusable modules. These components act as small building blocks which need to be assembled to represent a business process. The framework provides the basis of test automation and simplifies the automation effort.
The main advantage of a
framework
A framework is a generic term commonly referring to an essential supporting structure which other things are built on top of.
Framework may refer to:
Computing
* Application framework, used to implement the structure of an application for an op ...
of assumptions, concepts and tools that provide support for automated software testing is the low cost for
maintenance. If there is change to any
test case then only the test case file needs to be updated and the
driver Script
Driver may refer to:
Transportion
* A person whose occupation is driving
** Chauffeur, a person who drives an automobile as a job
** Motorman (locomotive), an electric vehicle driver
** Bus driver
** Truck driver
* SS ''Empire Driver'' or SS '' ...
and
startup script will remain the same. Ideally, there is no need to update the scripts in case of changes to the application.
Choosing the right framework/scripting technique helps in maintaining lower costs. The costs associated with test scripting are due to development and maintenance efforts. The approach of scripting used during test automation has effect on costs.
Various framework/scripting techniques are generally used:
# Linear (procedural code, possibly generated by tools like those that use record and playback)
# Structured (uses control structures - typically ‘if-else’, ‘switch’, ‘for’, ‘while’ conditions/ statements)
#
Data-driven (data is persisted outside of tests in a database, spreadsheet, or other mechanism)
#
Keyword-driven
# Hybrid (two or more of the patterns above are used)
# Agile automation framework
The Testing framework is responsible for:
# defining the format in which to express expectations
# creating a mechanism to hook into or drive the application under test
# executing the tests
# reporting results
Test automation interface
Test automation interfaces are platforms that provide a single
workspace for incorporating multiple testing tools and frameworks for
System/Integration testing of application under test. The goal of Test Automation Interface is to simplify the process of mapping tests to business criteria without coding coming in the way of the process. Test automation interface are expected to improve the efficiency and flexibility of maintaining test scripts.

Test Automation Interface consists of the following core modules:
* Interface Engine
* Interface Environment
* Object Repository
Interface engine
Interface engines are built on top of Interface Environment. Interface engine consists of a
parser and a test runner. The parser is present to parse the object files coming from the object repository into the test specific scripting language. The test runner executes the test scripts using a
test harness.
Object repository
Object repositories are a collection of UI/Application object data recorded by the testing tool while exploring the application under test.
Defining boundaries between automation framework and a testing tool
Tools are specifically designed to target some particular test environment, such as Windows and web automation tools, etc. Tools serve as a driving agent for an automation process. However, an automation framework is not a tool to perform a specific task, but rather infrastructure that provides the solution where different tools can do their job in a unified manner. This provides a common platform for the automation engineer.
There are various types of frameworks. They are categorized on the basis of the automation component they leverage. These are:
#
Data-driven testing Data-driven testing (DDT), also known as table-driven testing or parameterized testing, is a software testing methodology that is used in the testing of computer software to describe testing done using a table of conditions directly as test inputs a ...
#
Modularity-driven testing
#
Keyword-driven testing
Keyword-driven testing, also known as action word based testing (not to be confused with action driven testing), is a software testing methodology suitable for both manual and automated testing. This method separates the documentation of test cas ...
#
Hybrid testing
Hybrid testing is what most frameworks evolve/develop into over time and multiple projects. The most successful automation frameworks generally accommodate both grammar and spelling, as well as information input. This allows information given to ...
#
Model-based testing
Model-based testing is an application of model-based design for designing and optionally also executing artifacts to perform software testing or system testing. Models can be used to represent the desired behavior of a system under test (SUT), or ...
# Code-driven testing
#
Behavior driven development
What to test
Testing tools can help automate tasks such as product installation, test data creation, GUI interaction, problem detection (consider parsing or polling agents equipped with
test oracle
In computing, software engineering, and software testing, a test oracle (or just oracle) is a mechanism for determining whether a test has passed or failed. The use of oracles involves comparing the output(s) of the system under test, for a given ...
s), defect logging, etc., without necessarily automating tests in an end-to-end fashion.
One must keep satisfying popular requirements when thinking of test automation:
*
Platform and
OS independence
* Data driven capability (Input Data, Output Data,
Metadata
Metadata is "data that provides information about other data", but not the content of the data, such as the text of a message or the image itself. There are many distinct types of metadata, including:
* Descriptive metadata – the descriptive ...
)
* Customization Reporting (DB
Data Base
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases span ...
Access,
Crystal Reports)
* Easy debugging and logging
*
Version control friendly – minimal binary files
* Extensible & Customization (Open
APIs to be able to integrate with other tools)
* Common Driver (For example, in the Java development ecosystem, that means
Ant or
Maven and the popular
IDEs). This enables tests to integrate with the developers'
workflows
A workflow consists of an orchestrated and repeatable pattern of activity, enabled by the systematic organization of resources into processes that transform materials, provide services, or process information. It can be depicted as a sequence of ...
.
* Support unattended test runs for integration with build processes and batch runs.
Continuous integration servers require this.
* Email Notifications like
bounce messages
* Support distributed execution environment (distributed
test bed
A testbed (also spelled test bed) is a platform for conducting rigorous, transparent, and replicable testing of scientific theories, computational tools, and new technologies.
The term is used across many disciplines to describe experimental rese ...
)
* Distributed application support (distributed
SUT)
See also
*
List of GUI testing tools
GUI testing tools serve the purpose of automating the testing process of software with graphical user interfaces.
References
{{reflist
GUI
The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, i ...
*
List of web testing tools
This is a list of Web testing tools, giving a general overview in terms of features, sometimes used for Web scraping.
Main features
Web testing tools may be classified based on different prerequisites that a user may require to test web applica ...
*
Continuous testing
*
Fuzzing
*
Headless browser
A headless browser is a web browser without a graphical user interface.
Headless browsers provide automated control of a web page in an environment similar to popular web browsers, but they are executed via a command-line interface or using netwo ...
*
Software testing
*
System testing
System testing is testing conducted on a complete integrated system to evaluate the system's compliance with its specified requirements.
System testing takes, as its input, all of the integrated components that have passed integration testing. ...
*
Unit test
References
General references
*
*
*
* Roman Savenkov: ''How to Become a Software Tester.'' Roman Savenkov Consulting, 2008,
*
*
* Hayes, Linda G., "Automated Testing Handbook", Software Testing Institute, 2nd Edition, March 2004
* Kaner, Cem,
Architectures of Test Automation, August 2000
External links
Practical Experience in Automated TestingTest Automation: Delivering Business ValueTest Automation Snake Oilby James Bach
When Should a Test Be Automated?by Brian Marick
Guidelines for Test Automation framework
Advanced Test Automationby Hans Buwalda
Automation That Learns: Making Your Computer Work for Youby Jeremy Carey-Dressler
Automation Testing Resources & Best Practicesby Joe Colantonio
List of websites to practice test automationby Mayur S
Test Automation Starter Packby Bala
{{DEFAULTSORT:Test Automation
Software testing
Automation software