Selenium WebDriver. Gianluca Carbone. Selenium WebDriver 1

Transcription

1 Selenium WebDriver Gianluca Carbone Selenium WebDriver 1

2 Contents What is Selenium? History WebDriver High-Level Architectures Architectural themes Non Functional quality Layers & Javascript Design issues Firefox driver IE driver Who use Selenium Future problems Demonstration of a driver Selenium WebDriver 2

3 What is Selenium? Selenium is a set of tools for cross-platform automated testing of web applications. Open Source Web Application Testing System Automated UI Testing Functional type of tests Multiple browsers, multiple languages Selenium WebDriver 3

4 Selenium History Selenium WebDriver 4

5 Selenium(1)-Overview Selenium Core: JavaScript Framework - IDE Firefox Plugin - Remote Control Javascript code of Selenium Core Server: Proxy to launch browsers Client libraries - Grid Distributed remote tests Selenium WebDriver 5

6 WebDriver A platform and language-neutral interface that allows programs or scripts to introspect into, and control the behavior of a web browser.(w3c) Clean & Object Oriented API Java bindings Attempted to bind natively to the browser HtmlWebDriver Overcomes the limitation of Selenium RC Same Origin Policy Selenium WebDriver 6

7 Selenium 1.0 Architecture High level architecture Selenium WebDriver 7

8 Selenium 2.0 Architecture High level architecture Selenium WebDriver 8

9 Architectural themes Keep the costs down Emulate the user Prove the drivers work but you should not need to understand how everything works Lower the bus factor Have sympathy for Javascript implementation Every method call is an RPC call We are an Open Source project Selenium WebDriver 9

10 Non-functional quality - Scalability - Portability - Compatibility - Integrability/Reusability - Customizability - Usability - Testability - Ease of support - Resilience/Maintainability Selenium WebDriver 10

11 Layers and Javascript A browser automation tool is essentially built of three moving parts: 1. A way of interrogating the DOM (Document Object Model) 2. A mechanism for executing Javascript 3. Some means of emulating user input Language : Javascript Selenium makes use of a layeredset of libraries Selenium WebDriver 11

12 Layers and Javascript(2) Adapter layers: in order to meet the API contracts of both WebDriver and Core. Atoms: that provides functions for simple tasks or complex actions. Google s Clousure Library: which supplies primitives and a modularization mechanism allowing source file to be kept focused and small as possibile Selenium WebDriver 12

13 Issue Operating Systems, Drivers and Programming Languages supported: Operating Systems : Bindings: C#, Java, Ruby, Python, (Phpand Perl made by third part). WebDriverAPI: Selenium WebDriver 13

14 Issue(2) Simplified Architecture -> Selenium Server NOT needed. - using only the WebDriverAPI - browser and tests will all run on the same machine Otherwise you need it : - Selenium Grid; - Connect to a remote machine with a particular browser - Not using the Java bindings and would like to use HtmlUnitDriver Selenium WebDriver 14

15 Issue(3) Dealing with Combinatorial Explosion Reducing the number of language Reducing the number of supported browsers Make all the browsers look identical to the language bindings with a uniform interface. Have sympathy for a JavaScript Implementation Problem in the future, already with HTML 5 Do not worry! Flaws in the WebDriver Design RenderedWebElement Interface Documentation Binding tightly to a browser HTTP status code! Selenium WebDriver 15

16 Issue (4) -Architectural Style & Design Pattern Architectural Style Layered Plugin Born as a plugin for firefoxand always new features can be added to it Design Patterns Components Interoperability Enable communication between different platform (Web driver and Selenium Core) Composition Reuse of an existing applications Selenium Core Build system out of the composition of existing ones Selenium WebDriver 16

17 ISSUE (5) Firefox Driver Transport mechanism RPC HTTP Single or multiple end points REST-ish SOAP (single end-point) REST (multiple end-points) Encoding data based on content type negotiation HTML XML JSON Selenium WebDriver 17

18 Firefox Driver Overview of the Firefox Driver Architecture HTTP server XPCOM by Selenium HTTPD by Mozilla Error handling(two level) 1. invalid request 2. failed commands Selenium WebDriver 18

19 ISSUE (6) Internet Explorer Driver Language to use for programming on Windows C# 4 C++ In order to get the Java classes communicating with the C++ JNI (Java Native Interface) JNA (Java Native Architecture) Thread Boundary No Yes Java is multi-thread and IE COMs have single thread. It is solvedtaking the IE instance in a separate thread and using the PostThreadMessageWin32 API to communicate across the thread boundary. Selenium WebDriver 19

20 IE Driver Architecture IE Driver Selenium WebDriver 20

21 Who uses Selenium Selenium WebDriver 21

22 Future problems Selenium WebDriver 22

23 Demonstration of a driver I hope to be on time! Small Demo. Driver: Selenium WebDriver 23

24 Reference The Architecture of Open Source Application Selenium WebDriver Simon Stewart Official Web site of Selenium Selenium WebDriver 24