What is the Document Object Model (DOM) browser extension?

In this article we shall talk about the DOM browser extension of the silk test. But before coming to this topic we shall discuss a little about the DOM or the document object model. 

What is Document Object Model (DOM)?

- There was a need for a language and cross platform independent convention for the representation and interaction with the objects consisted in XHTML, HTML, XML etc documents. 

- Out of this need, only document object model was born. 

- Certain object methods are used for addressing as well as manipulating the objects present in the DOM tree.

- It is in the API or application programming interface where the public interface of the document object model is specified. 

- For rendering any of the documents mentioned above, an internal model quite similar to the document object model is used by most of the web browsers. 

- The nodes of all the documents are organized in a tree like structure which is commonly known as the DOM tree. 

- The top most node of this tree is termed as the document object.

- The HTML is downloaded in to the local memory and is parsed whenever a document is rendered in a browser. 

- Parsing is done using the DOM for the construction of the internal data structures that are employed for displaying the page in the browser window. 

- DOM’s application programming interface is also used by the java script for the inspection and modification of a web page. 

Use of DOM Browser Extension in SilkTest

- It acts as an add – on component that helps a big deal in the testing of the web applications. 

- A direct communication with the web browser is established by the DOM browser extension so that the recognition, categorization and manipulation of the objects on a web page can be made possible. 

- This direct communication with the web browser is established by the DOM browser extension.

- It is done by actually working with the HTML code rather than making use of the visual pattern recognition as relied on by the other such extensions or add ins. 

- The technique of visual pattern recognition is usually used by the virtual object browser extension. 

- The DOM browser extension identifies an object in a web application through the following steps:

1. The web browser window in which the application is current executing is identified.
2. Then the web UI object is identified that is based up on the HTML element representing the UI object.

- The whole identification of a UI web application object is possible only with the concatenation of the HTML element identification and the browser window identification.

- This document object model of the silk test makes use of the DOM standard stated by the W#C or World Wide Web consortium. 

- However, this DOM standard is currently supported by two web browsers namely Netscape 6 and internet explorer 5+ versions. 

- These two web browsers allow the external applications such as the silk test for making direct queries to the browser for obtaining information regarding the web page that is currently being displayed. 

- When the DOM browser extension is enabled on the host machine, an extension file is included so that the extension classes are made available to the user. 

- The silk test always makes sure that the extension classes are always visible in the library browser. 

- This is done so by addition of the of the help file of the extension (browser.ht) to the help files. 

- The properties defined for the DOM browser extension are merged with the default property sets which include the following:

1. Color
2. Font
3. Values and
4. Location