Don’t use assertTrue to verify a textMarch 13, 2020
WebDriverManager is an excellent tool to automate the management of the browser driver binaries running your automated test scripts locally with Selenium WebDriver and Java.
A simple and small example, if you don’t know this tool is:
The main thing here is the code on line 6. The
WebDriverManager class has a method with the name of the browser, like a chained method. Following if you use the
setup() method this class will download the browser binary according to your operating system and set the binary path.
What is a Browser Factory
Factory is a Design Pattern. It’s used when we need to create an object that shares a common implementation. In this context about browser creation, it will use methods like
We have, sometimes, different approaches for a Browser Factory. Below you can see one possible approach:
Basically you have an interface (
DriverManager) that has the implementation for each browser (
quit). They are separated because each browser has its own way to implement certain configurations.
We must create a factory to instantiate the correct browser. On the diagram, you can see an enumeration to support browser creation.
The TestClasses uses the
DriverManagerFactory to create the browser instance.
This approach is a good one, of course with a
BaseTest and some configuration to easily create multi-browser support, but if you have to create an approach or execute your tests locally we can apply a light way implementation with
Browser Factory with WebDriverManager
Since version 3.8.1 you can now use an enumeration to set up and initiate the target browser.
Line 8 set the
DriverManagerType enum to Chrome.
Line 9 shows the browser setup, passing the enum (Chrome) as a parameter to
Line 10 is getting the full class name, from the enum, to create a class.
Line 11 creates a new instance of that class.
Did you figure out that the enum
DriverManagerType has the full class name? You now can generate a browser factory with few lines of code.
How to create it
Try to follow, first, what we need to do:
- Create a class with a method that will receive the browser name
- Convert the browser name to the enum
- Get the full class name from the enumeration and create a class
- Set up the browser (binary and path)
- Instantiate the browser and return it
Now look at the code below:
Line 4 is a method that receives a browser name as a parameter and returns a
Line 8 transforms the browser name as a
DriverManagerType if the name matches.
Line 9 gets the received browser complete class name from the DriverManagerType and passes it to a generic class object.
Line 10 setup the driver (binary and path) for the received browser.
Line 11 creates a new instance of the browser.
Eg: if the received browser was chrome this line will, implicitly, do:
Line 17 returns the browser instantiated and ready for use on your test class.
You can have these benefits:
- Only one code for browser factory creation
- Less code to maintain
- Fast solution for multi-browser
If you need to add additional configurations on the browser, like enable/disable headless mode, change the screen size and so on you should implement like shown on the explanation about browser factory.
Looking for a real example?
At selenium-java-lean-test-achitecture you can see an implementation of the local browser factory.
The application has a properties file. If you clone this project and execute in your machine the take a look at the file general.properties on
src/main/java/resources/conf folder. There’s a property
local, which means local execution.
Now open the LocalDriverManager class on
src/main/java/driver/local. It’s the same implementation of this post.
The BaseWeb class on
src/main/java/test, a base test, receive as a parameter the browser or use chrome if no browser is informed, create the
WebDriver instance send the browser information to the
DriverFactory. Your execution is set as local, so the
DriverFactory will instantiate the
LocalDriverManager to the browser informed.