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Designing an Automated Web Test Environment
By: Dion Johnson
Abstract
This paper offers an alternative to the typical automated test
scripting method of ‘record and playback now and enhance the
automation environment later’. It explores a regression automation
system design for testing Internet applications through the GUI,
along with scripting techniques to enhance the scalability and
flexibility of an automated test suite. This paper will present a basic
structure for an automated test environment, and will expand on
each of the items found in that structure. Web testing levels will be
laid out, along with a basic approach to designing test scripts
based on those web-testing levels.
Introduction
It is not very difficult these days to sell those who are involved in the IT industry on the
importance of regression automation – at least the theoretical importance. It seems as
though most understand and are able to spew out, with robotic precision, that:
1. Automation saves time
2. Automation can be run over and over again (repeatable)
3. Automation runs tests the same way each time, maintaining reliability
4. Automation is our friend…
The automation-inhibiting problem, however, is the belief that automation should require
no additional thought other than that which requires one to executing existing manual
test cases with an automation tool.
In order to facilitate the desire to crank out quick and thoughtless automated tests, the
industry is creating more and more “user friendly” GUI automation testing, many of which
are geared to web-based applications. These tools offer record and playback features
that generate code or code-less visual scripts that may test one’s application by simply
navigating through it. These applications, with their increased capabilities, can be
extremely helpful, but also add to the problem. One of the major selling points for some
of these applications is that, “With our application, you save a lot of time because you
don’t have to spend time thinking about, and planning out how you want to perform your
tests. You just record your steps, and our tool will put in the checks for you.” What they
fail to realize is that eventually, some thought will have to take place, be it proactive or
reactive, and reactive thought is almost always more time consuming.
It is important to avoid falling into the trap of believing that some magical tool is going to
eliminate the need for thinking and planning. This paper helps dispel that myth, along
with providing some specific information for designing an automation environment. The
design is specifically geared towards web test automation.
Common Approach
With many, getting an automation tool is like a kid getting a new toy – they jump right in
and start playing. And the resulting test suite, much like a child’s new toy, just doesn’t
last.
A common approach for test automation may include the following:
v Automate test only during “spare time”
v Jump right in and start recording scripts
v Add application checks with no particular method
v Add some parameterization later
v As time passes and the number of scripts increases, replace some of the
redundant code with functions
This approach presents several problems. Spare time automation keeps the entire effort
from getting the focus that it needs, and it is often at the forefront of all other automation
problems and stumbling blocks. Stumbling blocks such as hard to maintain scripts.
When scripts are simply recorded with no forethought or design, what typically happens
is that they won’t play back exactly as recorded, prompting the need for some patchwork
solution that gets the script to behave as desired. Patchwork solutions don’t consistently
work, or stand-up over time, making the script very hard to maintain.
Redundancy also results from this common approach to test automation. When the
same actions appear in several different places or scripts, and that action changes in the
application under test (AUT), the change will need to be reflected in all of the scripts that
use that action. Excessive rework and reactive function creation are the results.
The patchwork solutions and rework, along with any unforeseen issues that may occur
during a test run, will affect the performance of the script.
Another problem that occurs with this jump-in-head-first-approach is that it yields a onedimensional
suite of tests. In other words, the scripts are only readily available to be run
at one level, and in one location.
Improved Approach
Test automation involves developing test scripts, so the software tester is in effect
creating a software application. The test automation application should, of course, be on
a much smaller scale, than the larger application that it tests, because spending too
much time on automation, or trying to automate too much can be counter-productive. At
the same time, however, automation should be treated more like software development
projects. See Pettichord’s “Seven Steps to Test Automation Success” for more
information on this concept.
Part of treating test automation more like a software development project, is the design
phase. Manual test cases are often independent of each other; so creating automated
test cases solely from manual test cases will result in a group of independent test scripts
that all have to be maintained separately and differently. The improved approach to test
automation that this paper addresses, deals with creating an automation test
environment, instead of just creating scripts.
Prior to designing the automation environment the following considerations are made:
v Script maintainability and flexibility
v Script performance
v The different levels of testing
v The number of applications under test
v The number of environments testing takes place in
v The different browsers used to test the web applications
After the appropriate considerations are made, the following the steps can be taken to
design the automated web test environment:
v Create the appropriate directory/test suite structure
v Develop initialization and configuration parameters
v Create functions
v Design test scripts based on pre-defined testing levels
Considerations
Script maintainability and flexibility
The maintainability and flexibility of automated tests pose the following question – if the
application or data in the application were to change, how much work would it take to
update the automated test that accesses the changed portion of the application? The
automation environment and scripts need to be designed in a way that minimizes the
amount of work involved in maintenance.
Script performance
Performance is a major concern for software applications, particularly internet
applications. By the same token, performance of automated tests should also be of
concern. As mentioned earlier in this paper, one of the advantages of automating tests
is that the execution is faster than manual execution. If the performance of automated
tests is ignored or taken for granted, the time saved by running automated tests can be
drastically reduced.
Different levels of testing
In a perfect world, there would be an unlimited amount of time for testing…. Correction.
In a perfect world, there would be no need for testing, because the applications would
be developed with no bugs. Since we live in neither perfect world, it is necessary to
develop automated tests that are able to conform to the varying schedule that testers are
given from release to release, and even from build to build. Not all builds contain the
same types of things. Depending upon the nature of a build, the time given to test it may
vary from a few minutes to a few days (maybe more). Full regression may not always be
an option. Only certain types of testing actions might be allowed, and these different
types of actions comprise different levels of testing.
The number of applications under test
A software project that requires testing may consist of more than one AUT. When
responsible for automating tests for all of these applications, it is important to take into
consideration the things that each of these applications have in common and how they
are related, and design the automated test environment accordingly.
The number of environments testing takes place in
A software project may have several different environments that testing occurs in. Most
have at least the following three:
1. Functional test environment
2. Development environment
3. Production environment
Each environment may be on a different machine, connect to a different database, and
limit the types of testing that can be executed. The user shouldn’t have to go to several
different places to set up several different parameters every time the automation test
suite is ready to be run. The automation environment should account for the variations.
The different browsers used to test the web applications
Theoretically, If an application is required to be compatible with several different
browsers, it should be the same on all of those browsers it is compatible with. In
actuality, there may be several subtle differences among browsers that the automated
test environment should be equipped to deal with.
Design Steps
Create the appropriate directory/test suite structure
As mentioned before, test automation is a small-scale form of software development that
involves creating a software package. It is important for this package to have a preplanned
directory structure, for several reasons. First, it is important because one
obviously needs to know where things are going to go. Second it is important because
this package may need to be moved as a whole. The environment may need to be
copied and installed onto another machine. Creating a directory structure makes the
environment portable.
Develop initialization and configuration parameters/scripts
These are parameters/scripts that set up the environment before actually running the
scripts that test the AUT. These parameters basically control the other components of
the automated web test environment.
Create functions
Function creation does not have to begin after the test script creation. There are basic
actions that take place during testing, that one knows ahead of time will be executed
over and over again. So why wait until the test script creation begins? Create functions
for those highly repetitive actions at the beginning.
The function samples in this paper are geared towards automation tools with a scripting
language, but keep in mind that functions should be created when using automation
tools that use visual script, also. Many of these applications provide a way to reuse
blocks of script.
Design test scripts based on pre-defined testing levels
Designing testing levels was discussed under the Considerations sub-heading.
Specific web test levels will be discussed later on in the paper.
Directory Structure
Environment Root Directory
Init Config GUI Map Function Driver Test
Script Script Files Library Script Scripts
There are several components of the automated test environment. Above is a chart
displaying a pictorial representation of how the components fit into the environment.
Below is a list containing component definitions. It may also be necessary to create a
sub directory for each component shown.
Component Definitions
Init Script
The Init Script (initialization script) brings the environment to a controlled stable point. If
the environment is initialized, there is a better chance of the test scripts running properly.
Some specific initialization parameters will be discussed later.
Config Script
The Config Script (configuration script) sets certain parameters needed for the test run.
Some specific configuration parameters will be discussed later.
GUI Map Files
Whether or not this component exists, depends on what tool is used. The name “GUI
Map” comes from Mercury Interactive’s WinRunner tool. Other tools may have
something similar to a GUI Map, but it may have a different name. The GUI map serves
as an interpreter that enables the automation tool (i.e. - WinRunner) to communicate
with the AUT.
Function Lib
The Function Lib (function library) is a set of functions used in the test suite. It is
normally loaded at the beginning, and functions are called from it throughout the test run.
Some specific types of functions will be discussed later.
Driver Script
This is the script that coordinates test activities by calling other scripts. It controls
everything that takes place during the test run. The driver is what allows the execution
of several scripts, without supervision. It may run initialization scripts, set up
configuration parameters, load GUI maps, and run test scripts.
Test Scripts
These are the components that actually perform tests, and verify that the AUT works as
desired. The two actions listed in Example 1 is a representation of a test script. Test
scripts perform actions, and generate results files.
Initialization Scripts
The main difference between items that are placed in the initialization scripts and items
place in the configuration scripts is that items in the initialization script are not likely to
change from test run to test run, or from machine to machine. Settings in the
initialization script are going to remain fairly constant throughout the project life cycle, but
may change occasionally. There are two basic types of initialization scripts.
v Automation Tool Initialization Scripts
v AUT Initialization Scripts
Automation Tool Initialization Scripts
The Automation Tool Initialization Scripts initialize the automation tool, by doing several
things. These scripts may load compiled modules, such as function libraries, so that
they may be used throughout the time the automation tool is in use. They may
customize GUI Maps, and may include global wait/think times, and directory path
variables.
AUT Initialization Scripts
The AUT Initialization Scripts initialize the application under test. There are some very
specific tasks that need to be executed when dealing with a web AUT, however, that are
probably not a concern for other client/server applications. These tasks include:
v Clearing the cache
v Setting cookies
v Setting frame format
Clearing the cache
Miller talks about the importance of clearing the cache in his paper entitled, “WebSite
Testing”. Under the heading, WEBSITE TEST AUTOMATION REQUIREMENTS, he
asserts that since caching can improve the apparent performance of the web site, it
should be cleared in order to get an accurate picture of the site response time. This is a
good point, but it may be argued, by some, that the response time is of little concern
when doing functional testing; the response times, it may be asserted, will be measured
during the load/stress testing. There is an additional reason that the cache should be
cleared, however. When dealing with Internet applications, it is common place for an
action to change the make-up of the application. The cache saves this new make-up,
which may cause a problem for automated test scripts, because the test scripts may be
looking for the default make-up during script execution.
Look at the following line of HTML code for example:
<BODY BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#000080" VLINK="#FFFF00"
ALINK="#C0C0C0" >
This line of code, in reference to the link, is saying that the color of the link prior to being
clicked is navy; while it is being clicked, it is yellow; after it is clicked, the color is silver.
The silver color of the clicked link is cached, so that even after leaving that page and
bringing it back up, the link will be silver instead of navy. This could pose a problem for
automation scripts when performing link validation. If it is looking for a link to be navy,
but it is silver instead, an unnecessary failure will be generated in the results.
Unnecessary failures compromise the integrity of the results.
Setting Cookies
Cookies are short pieces of data used by web servers to help identify web users, and
they have the ability to change certain site behavior. When this is the case, it is
important to create a set of initialization steps that ensure the application behaves as
expected.
Consider the following scenario. There exists a web page with two frames as seen
below.
|----------|-----------------------
| line 1 |
| |
| line 2 |
| | Button 1
| |
------------------------------------
The left frame has two links, while the right frame has a button. Clicking on Link 1 will
bring up a new page called Page 1, while clicking on Link 2 will bring up a new page
called Page 2. Clicking on Button 1 brings up a new page, but the page that comes up
all depends on which of the two was clicked last. Each time one of the two links is
clicked a cookie is set on the server with information that specifies which link was
clicked. Based on the setting of this cookie, Button 1 may bring up Page 1 or Page 2.
In order to have a controlled environment, it is important to know what functionality is to
be expected out of Button 1. An initialization routine in this case, may simply involve
automating the process of clicking on Link 1 at the beginning of a test run.
Setting Frame Format
With Internet applications, it is not unlikely for pages to change their formats (table
arrangements, object names) based on certain actions, page handlers, etc. It therefore
becomes important to create an initialization routine that stabilizes the frame format.
Configuration Files/Scripts
Under the Improved Approach heading and Design Steps sub-heading, it mentions
initialization and configuration jointly. That’s because there is a fine line between
initialization elements and configuration elements. As alluded to in the previous section,
the main difference between the two is that the configuration elements are those
elements that will need to be changed more frequently.
The Considerations sub-heading under the Improved Approach heading lists several
items that need to be considered before designing the automation environment, and
these items were discussed in detail. The Configuration file/script is what manages how
these considerations are put into action in the automation test suite.
More information on how configuration components are used in the scripts will be given
under the Test Scripts heading.
Function Library
The next step in designing an automated web test environment is the creation of
functions. There are some basic types of functions that will, without a doubt, be used
throughout the automation effort, and should be created prior to the creation of
automated tests. These function types are as follows:
v Login functions
v Navigation functions
v Error handling functions
v Loading functions
v Miscellaneous verification functions
o Window check
o Date/time check
o Account number/login ID check
Login Functions
These are the functions that login and logout of the AUT, and other supporting
applications. The login and logout processes are going to executed several times during
a test run, and are composed of very basic steps, so these functions should not be
difficult to create.
The login functions should be tied to several configuration parameters, such as the user
ID, and password configuration parameters.
Navigation Functions
Most applications have several main areas that are navigated to many times during
testing. For example, an application may have a Main page, a FAQ (Frequently Asked
Questions) page, an Account Services page, and several Orders pages.
Navigation for these different areas may be as follows:
Page Navigation
Main Main
FAQ Main --> Account Services --> FAQ
Account Services Main -->Account Services
Orders 1 Main --> Orders --> Orders 1
Orders 2 Main --> Orders --> Orders 2
These paths are fairly basic, and can be put into functions at the very beginning of the
automation process.
Error Handling Functions
Error handling functions are functions created to deal with certain unexpected events
that may occur during testing. If nothing is set up to handle these events, they could kill
automation run completely. Internet applications have a fairly standard set of events that
occur regardless of the application. The list of events includes popup security windows,
information windows, and error windows, along with the page cannot be found frame.
Good portions of the events that will have to be handle require nothing more than
clicking an OK button to close the popup window. Many of these events can be turned
on and off in the browser, but some can’t be. For those that can’t be turned off, routines
should be created to handle them.
Loading Functions
Loading functions do exactly as the name implies – load things. These functions load
files and compiled modules for use by the automation tool. For example, in WinRunner,
GUI Map files need to be loaded. When several GUI Map files exist, it becomes much
simpler to put all of the load statements into a single routine, and execute them by
running that one routine.
Miscellaneous Verification Functions
Although most automation tools have built in checks that can be used to verify certain
application attributes, there are times when user defined checks are much more efficient.
Some user-defined checks that one may want to create include the following:
Window check
Date/time check
Account number/login ID check
Window check
The Window check function’s purpose is to verify that a specified window or frame
appears. The biggest reward that can come from using the Window check function
comes in the area of script performance. Most automation steps and verifications occur
inside of window or frame. If the window or frame does not appear, the tool wastes time
trying to execute steps in a window that does not exist. The Window check function
creates the ability to first check for the existence of a window, then make the execution
of the following steps contingent upon whether or not that window exists.
Date/time check
This is a handy function to have when the date and time need to be verified in the
application. Since the date and time are dynamic fields, this function simply takes the
system clock information, puts each element (day, hour, minute, etc.) into an array, and
compares these elements to the date/time elements in the application.
Account number/login ID check
Web sites often have the account number or login ID listed on every page. Since the
exact same thing is being checked on every page, and the results for each page should
be exactly the same, it only makes since to have a function that does this check. This
function will use the login configuration parameter in its verification.
The login ID will normally follow some text that reads, “Login:” or “Account Number:” so
creating this function will simply involve performing some kind of text check on the data
that follows the “Login:” or “Account Number:
Test Scripts
The final step in the design phase is designing the test scripts. The way an individual
test script is designed actually depends on the user’s AUT, but what this section does is
reveal how to incorporate web test levels into that design. The importance of this
concept is presented in the Improved Approach section.
In order to understand how to design a test script based on web test levels, it is
necessary to first break down the concept of web testing. The following list is comprised
of steps that separate web testing into components, and displays how to put those
components together to form basic web test levels.
v Examine the microscopic view of web testing
v Examine the macroscopic view of web testing
v Develop web test levels
Examine the microscopic view of web testing
Looking at web testing through a microscope yields that just about every type of web
testing is composed of the following checks:
v Server response time verification – testing to make sure the web site’s response
to certain actions doesn’t exceed a reasonable amount of time
v Content Verification – verifying the layout and size of frames and tables;
verifying text and returned data; verifying URLs
v Cosmetic Verification – verifying actual fonts, colors, and object positioning
appears correctly.
Examine the macroscopic view of web testing
From the macroscopic view, there are three testing categories:
1. Link testing
2. Application testing
3. HTML testing
Link testing
Link testing involves both checking and testing links. The difference between checking a
link and testing a link is fairly simple. Checking a link involves checking the link’s
properties to make sure the link is pointing to the correct URL. Testing a link involves
actually clicking on that link to ensure that the resulting page is correct, and has the
proper attributes.
Application testing
Application testing verifies that the AUT has the correct functionality. For example, if the
application places orders, a test would verify that the order was placed properly.
Parameterization is normally a big part of application testing, because several sets of
data are often used to test the same piece of functionality.
HTML testing
HTML testing verifies that the HTML code follows proper conventions, and doesn’t have
errors.
Develop web test levels
When developing web test levels, it is important to evaluate the needs of the AUT’s
project environment. This section presents some basic levels based on an evaluation of
web testing in general, but one should feel free to expand upon these levels in one’s
own environment.
As discussed before, different levels of testing are developed to give the ability to focus
automation executions on varying aspect of the testing cycle. This is important;
especially when time is limited. Often times when performing manual testing, a project
lead may tell the test lead that the test team has two days to focus on a full build, or a
half day to focus on a build that incorporates only application changes. It is possible that
the project lead may go and tell the test lead that the test team has thirty minutes to test
a build that just focuses on link changes, after which time the build is going to be pushed
into production as an emergency patch.
Just as one should be equipped to honor the request when executing tests manually, so
should one be equipped honor the request when executing tests through an automated
process. The testing levels listed in this section give that ability.
From the macroscopic view of web testing, it can be deduced that there are two basic
types of test scripts:
1. Link test scripts
2. Application test scripts
HTML testing will not be address in this paper, because a developer normally does it.
Then combining the elements from the microscopic view of web testing with the
elements from the macroscopic view of web testing the following web test levels can be
derived:
v Application Tests
v Link Tests
v Link Checks
v Parameterization On/Off
v Cosmetic Checks On/Off
v Content Checks On/Off
v Combination of all of the above
The application test level and the link test levels can be controlled by simply
picking which scripts to run. The other test levels can be incorporated into the
test script and controlled by mapping each to a configuration parameter that
accepts the values “On” and “Off”.
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