Selenium Grid

Selenium Grid:

Well, I have experienced the following scenarios while setting up the grid environment for the first time. 

Here it is, I have two machine, say '10.19.137.247' (test machine) and 192.168.1.113 (test dev machine) so to start the hub on test machine I have run the following command:

On Test Machine:

    java -jar selenium-server-standalone.jar -role hub

The following message or information appeared on command line as a result

Mar 10, 2014 2:57:03 AM org.openqa.grid.selenium.GridLauncher main
INFO: Launching a selenium grid server
2014-03-10 02:57:26.332:INFO:osjs.Server:jetty-7.x.y-SANPSHOT
2014-03-10 02:57:26.395:INFO:osjsh.ContextHandler:started o.s.j.s.ServletContextHandler{/,null}
2014-03-10 02:57:26.410:INFO:osjs.AbstractConnector:Started SocketConnector@0.0.0.0:4444     

On Test Dev machine:

 java -jar selenium-server-standalone -Dwebdriver.chrome.driver=C:\Users\Fayaz\Downloads\chromedriver.exe -role webdriver -hub http://10.19.137.247/grid/register

The following message or information appeared on command line as a result

Mar 10,  2014 12:30:36 PM org.openqa.grid.selenium.GridLauncher main
INFO: Launching a selenium grid node
Mar 10, 2014 12:30:39 PM org.openqa.grid.internal.utils.SelfRegisteringRemote startRemoteServer
WARNING: error getting the parameters from the hub. The node may end up with wrong timeouts. Connection refused: connect
12:30:39.255 INFO - Java: Oracle Corportation 24.45-b08
12:30:39.263 INFO - OS:Windows 7 6.1 x86
12:30:39.295 INFO - v2.39.0, with Core v2.39.0. Built from revision ff23eac
12:30:39.565 INFO - Default driver org.openqa.selenium.iphone.IPhoneDriver registration is skipped: registration capabilities Capabilites [{platform=MAC, browserName=iPhone, version=}] does not match with current platform: VISTA
12:30:39:565 INFO - Default driver org.openqa.selenium.iphone.IPhoneDriver registration is skipped:
registration capabilities Capabilities [{platform=MAC, browserName=iPad, version=}] does not match with current platform: VISTA
12:30:39.648 INFO - RemoteWebDriver instances should connect to : http://127.0.0.1:5555/wd/hub
12:30:39.649 INFO - Version Jetty/5.1.x
12:30:39.650 INFO - Started HttpContext[/selenium-server/driver./selenium-server/driver]
12:30:39.651 INFO - Started HttpContext[/selenium-server,/selenium-server]
12:30:39:652 INFO - Started HttpContext[/,/]
12:30:39:654 INFO - Started org.openqa.jetty.jetty.servlet.ServletHandler@12132a6
12:30:39.654 INFO - Started HttpContext[/wd,/wd]
12:30:39.657 INFO - Started SocketListener on 0.0.0.0:5555
12:30:39.658 INFO - Started Started org.openqa.jetty.jetty.Server@a4b9da
12:30:39.661 INFO - using the json request : {"class":"org.openqa.grid.common.RegistrationRequest","capabilities":[{"platform":"VISTA","seleniumProtocol":"Selenium","browserName":"*firefox","maxInstances":5},{"platform":"VISTA","seleniumProtocol":"Selenium","browserName":"*googlechrome","maxInstances":5},{"platform":"VISTA","seleniumProtocol":"seleniumProtocol":"WebDriver","browserName":"chrome","maxInstances":1},{"platform":"VISTA","seleniumProtocol":"WebDriver","browserName":"internet explorer","maxInstances":1}],"configuration":{"port":5555,"register":true,"host":"192.168.1.113","proxy":"org.openqa.grid.selenium.proxy.DefaultRemoteProxy","maxSession":5,"role":"node","hubHost":"10.19.137.247","registerCycle":5000,"hub":"http://10.19.137.247/grid/register","hubPort":-1,"url":"http://192.168.1.113:5555","remoteHost":"http://192.168.1.113:5555"}}
12:30:39.664 INFO - Starting auto register thread. Will try to register every 5000 ms.
12:30:39.664 INFO - Registering the node to hub :http://10.19.137.247:-1/grid/register
12:30:41.466 INFO - couldn't register this node : Error sending the registration request.
12:30:48.264 INFO - couldn't register this node : Hub is down or not responding: Connection refused: connect

If we observer on the test machine to verify the status of the selenium web server whether the client / node is connected or not, in other words when no node connects to hub using selenium grid, it will looks like in the screen shot

When no nodes connects to a hub using selenium grid then the server details displayed

This error has been resolved after I corrected the command to connect the hub from my test dev machine, and the changed command is

java -jar selenium-server-standalone.jar -Dwebdriver.chrome.driver=C:\Users\Fayaz\Downloads\chromedriver.exe -role webdriver -hub http://10.19.137.247:4444/grid/register

The difference here is I am using port number ':4444' after test machine URL

After connecting to the server, we can verify the status of the selenium web server whether the client / node is connected or not, it will looks like in the screen shot

When a node connects to hub using selenium grid then the list of details displayed

The path in browser to see list of clients or nodes connected to a hub at server / hub side is,

 localhost:4444/grid/console

For a beginner most common and exception can occur as follows, part of exception pasted

Caused by: java.lang.IllegalStateException: The path to the driver executable must be set by the webdriver.chrome.driver system property;

For more info please find the source here

To handle ssl or certification errors on a remote browser, I have used the following code and it worked like a charm

For IE or Chrome:
  remoteWebdriver.navigate().to("javascript:document.getElementById('overridelink').click()");
//I assume you have already had a wed driver reference called 'remoteWebdriver'


Now, to take screen shot of the remote test script execution, you can find the code in this selenium webdriver cheat code or from here

Update :


From the latest release of selenium 3.x, if we use above command to register client to remote hub then we get the following exception

Exception in thread "main" com.beust.jcommander.ParameterException: Unknown option: -Dwebdriver.chrome.driver=C:\Users\Fayaz\Downloads\chromedriver.exe
        at com.beust.jcommander.JCommander.parseValues(JCommander.java:742)
        at com.beust.jcommander.JCommander.parse(JCommander.java:282)
        at com.beust.jcommander.JCommander.parse(JCommander.java:265)
        at com.beust.jcommander.JCommander.<init>(JCommander.java:210)
        at org.openqa.grid.selenium.GridLauncherV3$3.setConfiguration(GridLauncherV3.java:267)
        at org.openqa.grid.selenium.GridLauncherV3.buildLauncher(GridLauncherV3.java:155)
        at org.openqa.grid.selenium.GridLauncherV3.main(GridLauncherV3.java:75)




So the command to register a node / client is changed as follows:

                        java -jar selenium-server-standalone-3.3.1.jar -role node -hub http://<hub_ip>:4444/grid/register -port 4444