I'm curious what the Selenium class called "Service" is.
Would this be useful for setting up a Chrome driver as opposed to invoking a webdriver through my_driver = webdriver.Chrome(...)?
I looked up the docs but they're not helpful in describing the purpose:
https://selenium-python.readthedocs.io/api.html#module-selenium.webdriver.common.service
Service is the new class introduced in selenium 4 to start a webdriver:
from selenium import webdriver
from selenium.webdriver.chrome.service import Service
driver = webdriver.Chrome(service=Service(your_chromedriver_path))
The previous method is deprecated:
driver = webdriver.Chrome(executable_path=your_chromedriver_path)
in fact if you run it, then it raises a warning
DeprecationWarning: executable_path has been deprecated, please pass in a Service object
This service is introduce to manage the driver process. So that you can kill it after your tests are done.
Basically invoking quit does not put any obligations to webdriver to stop existing as the process. On the contrary webdriver is a service that is aimed to process concurrent sessions from different clients. So once your tests are stopped the webdriver might still be running.
When you start your tests using Service you now get an interface to kill that remote process using the obtained reference.
Related
Why is the code //RemoteWebDriver driver= new FirefoxDriver(); not used instead of //WebDriver driver= new FirefoxDriver() to create a driver object?
I feel that RemoteWebDriver gives more capabilities for the driver instance than webdriver reference. Can someone clarify this?
WebDriver will start up a web browser on the computer where the code instantiates it. For example. If you write a bit of code, and then run it to see how you are doing, the browser will pop up on your screen and you will see WebDriver begin to manipulate that web browser window (if everything went well!)
With a major exception which I will explain below, RemoteWebDriver will do the same thing; it will open and manipulate a browser window (if everything went well!) Generally speaking, You can actually switch the instatiation of a WebDriver with a RemoteWebDriver (well, there are advanced cases where you might not be able too do this) The major difference is that RemoteWebDriver sends that request to open and control a web browser to a server, so you normally wouldn’t see the browser open and do it’s thing.
Selenium server is the program that runs and waits for RemoteWebDriver connections. You can run it on your local computer to test it out. If you get it set up and running, you’ll be able to create a RemoteWebDriver and see that the Selenium server accepts the connection and allows you to control the web browser window.
The gains from using RemoteWebDriver?
If you can do connect to a local Selenium server, you can be confident that you have the knowledge and skills needed to connect to a remote Selenium server, or even to a paid service like SauceLabs (Hosting Selenium for you) that allows you to run lots of tests on lots of OS’s and lots of browsers without having to actually maintain or install any of them (Linux, Windows 8, Windows 10, MacOS, Andriod, IOS, IE, Firefox, Opera, Safari, Firefox Mobile, etc) You’ll want to look into running tests asynchronously at this point. You don’t have to run them one at a time, so can test a large number of OS/Browser variations in a very short time.
What does it mean when something is used only for client/server communication?
When you uses a Selenium grid with have one hub and multiple clients, you invoke RemoteWebDriver through which you instantiate the server and and make the request to it.
WebDriver is an interface in selenium which extends SearchContext interface (super most interface in selenium)
Where as RemoteWebdriver is a class which implements WebDriver,
We can use RemoteWebdriver, when we going to execute the test in romote environment,(selenium grid).
WebDriver interface will invoke the driver locally,
Currently in automation mostly we are using WebDriver only.
Grid not using widely.
WebDriver driver=new ChromeDriver() ;
driver is the reference variable where used to access chromedriver class.
Using driver instance we can access all the unimplemented methods available in WebDriver interface, also able to access all the properties available in chromedriver class.
For more details
https://www.softwaretestingmaterial.com/webdriver-driver-new-firefoxdriver/
I am super confused with selenium.
Completely new to automated testing and struggling to get a foothold with selenium.
http://www.seleniumhq.org/projects/webdriver/
I get the concept of writing tests and have done a few with in angular with protractor, but i need to use selenium for a particular project and not sure where to start.
To start with I just want to be able to write some simple client side tests, but i have no idea where to start with on Selenium, i read their docs but not really any the wiser..
A webdriver test is just a script, written in one of many compatible languages (java, python, etc). The script runs on any machine. During development it will typically run on your local machine, but eventually your test could run on a continuous integration server.
Webdriver has two modes of operation: it can open a browser on the same machine that the script is running, or it can send a request to a selenium grid hub, which will open a browser on one of its nodes.
As a simple example, here is a complete working example of a selenium test in python (taken from python selenium bindings Getting Started page):
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
driver = webdriver.Firefox()
driver.get("http://www.python.org")
assert "Python" in driver.title
elem = driver.find_element_by_name("q")
elem.send_keys("pycon")
elem.send_keys(Keys.RETURN)
assert "No results found." not in driver.page_source
driver.close()
If you have python and the selenium libraries installed, you can save this file to "example_test.py" and then run it from a command prompt with python example_test.py
Here's a similar test, this one in javascript, taken from the WebDriverJS User's Guide. You would run it the same way you run any javascript program.
var webdriver = require('selenium-webdriver');
var driver = new webdriver.Builder().
withCapabilities(webdriver.Capabilities.chrome()).
build();
driver.get('http://www.google.com');
driver.findElement(webdriver.By.name('q')).sendKeys('webdriver');
driver.findElement(webdriver.By.name('btnG')).click();
driver.wait(function() {
return driver.getTitle().then(function(title) {
return title === 'webdriver - Google Search';
});
}, 1000);
driver.quit();
To give you an organic answer to your question, when you run a selenium Firefox browser test, it starts a local ad-hoc "Selenium grid hub listener" on a port like 30005 or something at the start of the test. Then, the code that you write talks to that local port in JSON format by sending local http requests to localhost:30005 . The "Grid hub" listening on that port knows how to talk to your local web browser and controls it by answering commands passed through that port. At the end of the test, the "selenium grid hub listener port" closes.
If you do some reading and try to understand how the "Selenium Grid Hub" works and also learn about "WebDriver Wire Protocol", then it might help you start understanding what I explained above.
Always read the official Selenium docs for references, but if you are using Java, you can get a head-start by using the Conductor framework
It's a Java specific DSL, so won't work with any other.
A test would look like this:
#Config(url="http://google.com", browser=Browsers.CHROME)
public class MyTest {
#Test
public void testGoogle() {
// a quick google search
setText(By.name("q"), "something")
.click("[name='btnG']");
}
}
Running with local webdriver my test suite completes in 2.7hrs, Running a remote webdriver with hub/node setup the tests take 21.4hrs.
I'm looking for ways to pin point what is actually the cause of this significant overhead.
Notes so far
The build machine and all the hub and node machines are all VMs with the exact same specifications.
The Node and Hub hangs (40-50s which is fortunately less than the 60s timeout) on a very small number of find element calls.
Idle is not because my C# not calling the webdriver. It is waiting on the hub's response and the node does log that INFO - Executing: [find element: By.selector:..., the selector is a CSS selector.
Behaviour is the same for the IE driver.
For most of the FindElement calls I can replace them with a ExecuteScript call and use jQuery instead. In these cases I no longer hang/idle for 40-50s. Yet I can't replace all calls this way.
The issue was due to implicit waits being set, in the remote web driver initialisation (by another developer). Remove it and the behaviour returns to what I was wanting.
I'm trying to implement a java program that will execute simple selenese commands with a local webdriver.
is there an API that gets a string such as "clickAndWait" and executes it? The WebDriverCommandProcessor class doesn't seem to do the trick.
The WebDriver Java API is primarily the methods of WebDriver and WebElement. There is no method that takes a command string and executes it. But the Java API is a wrapper around another protocol, which is string-based. Check out the WebDriver WebDriver Wire Protocol, which is what a WebDriver language binding (client) uses to communicate with a WebDriver browser-driver (server). The commands do not map directly to "selenese" (the client language of Selenium IDE), but you can build the actions up to make them so.
I'm not sure I quite understand the difference. WebDriver API also directly controls the browser of choice. When should you use selenium remote control (selenium RC) instead ?
Right now, my current situation is I am testing a web application by writing a suite with Selenium WebDriver API and letting it run on my computer. The tests are taking longer and longer to complete, so I have been searching for ways to run the tests on a Linux server.
If I use Selenium Remote Control, does this mean I have to rewrite everything I wrote with WebDriver API?
I am getting confused with Selenium Grid, Hudson, Selenium RC. I found a Selenium Grid plugin for Hudson, but not sure if this includes Selenium RC.
Am I taking the correct route? I envision the following architecture:
Hudson running on few Ubuntu dedicated servers.
Hudson running with Xvnc & Selenium Grid plugin. (Do I need to install Firefox separately ?)
Selenium grid running selenium RC test suites.
I think this is far more time efficient than running test on my current working desktop computer with WebDriver API.
WebDriver is now Selenium 2. The Selenium and WebDriver code bases are being merged. WebDriver gets over a number of issues that Selenium has and Selenium gets over a number of issues that Webdriver has.
If you have written your tests in Selenium one you don't have to rewrite them to work with Selenium 2. We, the core developers, have written it so that you create a browser instance and inject that into Selenium and your Selenium 1 tests will work in Selenium 2. I have put an example below for you.
// You may use any WebDriver implementation. Firefox is used here as an example
WebDriver driver = new FirefoxDriver();
// A "base url", used by selenium to resolve relative URLs
String baseUrl = "http://www.google.com";
// Create the Selenium implementation
Selenium selenium = new WebDriverBackedSelenium(driver, baseUrl);
// Perform actions with selenium
selenium.open("http://www.google.com");
selenium.type("name=q", "cheese");
selenium.click("name=btnG");
Selenium 2 unfortunately has not been put into Selenium 2 but it shouldn't be too long until it has been added since we are hoping to reach beta in the next couple of months.
As far as I understand, Webdriver implementation started little later than Selenium RC. From my point of view, WebDriver is more flexible solution, which fixed some annoying problems of SeleniumRC.
WebDriver provides standard interface for testing web GUI. There are several implementations of this interface (HTTP, browser-specific and based on Selenium). Since you already have some WebDriver tests, you must be familiar with basic docs like this
The tests are getting longer and longer to complete, so I have been searching for ways to run the tests on a linux server.
Did you try to find actual bottlenecks? I'm not sure, that elimination of WebDriver layer will help. I think, most time is spent on Selenium commands sending and HTTP requests to system-under-test.
If I use sleneium remote control, does
this mean I have to rewrite everything
I wrote with WebDriver API ?
Generally, yes. If you did not implement some additional layer between tests code and WebDriver.
As for Selenium Grid:
You may start several Selenium RC instances on several different [virtual] nodes, then register them in Selenium Grid. Your tests connect to Selenium Grid, and it redirects all commands to SeleniumRC instances, coordinating them in accordance with required browsers.
For details of hudson plugin you may find more info here