So that we may perform front-to-back web UI testing, we are using Selenium and ChromeDriver to automate page loads/interaction as part of our testing pack.
This is behaving as expected during developer testing (on a developer's local machine), but we are struggling to perform these checks as part of our continuous integration build.
Our server plant is *NIX based, and all of our CI infrastructure runs on these machines. So that we may test Chrome under Windows (our delivery mechanism), we have configured a Selenium Grid. When the CI tests run, they access the grid, in order to locate a Windows node to run the tests on.
We have had a Windows desktop provisioned solely for the purpose of running these tests. This contains our standard enterprise build of Windows 7. This machine will be periodically rebooted in-line with the IT department's update policy.
In an effort to ensure the Selenium server is always running, we have added the Selenium Server (running in "node" mode) as a Windows service. The selenium Server is configured to start-up ChromeDriver to invoke the simulated user-interaction.
However, when running the tests from CI they fail due to timeout. Our working theory is, the system user that is running the service cannot create interactive windows. A web search has raised reference to the "Session 0" problem, but with little to no constructive advice on how to move forward.
Starting the Selenium Server process manually from an interactive session is not a viable solution, as this is leading to brittle tests - which are failing due to an infrastructure problem, rather than a genuine test regression.
How can we have an instance of Selenium Server started via a Windows Service whenever the system reboots, that is capable of launching Chrome instances?
It could be easily done with NSSM.
Installation of services looks like these:
nssm install seleniumhub java -jar C:\selenium\selenium-server-standalone-2.45.0.jar -role hub -hubConfig C:\selenium\hub.json
nssm install seleniumnode java -jar C:\selenium\selenium-server-standalone-2.45.0.jar -role node -nodeConfig C:\selenium\node.json
It provides easily way to remove service if needed:
nssm remove seleniumnode confirm
Add destination to nssm to your PATH variable and run from console as admin
UPDATE April 2021
NSSM is not supported for more than 3 years. So please consider other options like winsw or any other. WinSW does the same job as NSSM and allows to keep run configuration in xml.
You cannot run Selenium Grid as a windows service ever since Windows Vista. Microsoft calls it "Session 0 Isolation". You could do it in Windows 2000 or XP but since the time that Vista came out, Microsoft no longer will let Grid interact with the desktop (or any other UI programs for that matter). Regardless of the fact that you still see that "interact with desktop" checkbox, it is a red herring. So, you MUST run Selenium Grid in the foreground on that server in order for it to get access to the session. If it is running Windows Server, you could in theory have multiple sessions and leave Grid running in the foreground on one of the non-zero user sessions.
Right now you can't help it - it used to work fine in session 0 but for the past few days after chrome update only works for interactive sessions.
Related bugs:
https://code.google.com/p/selenium/issues/detail?id=8029
https://code.google.com/p/chromium/issues/detail?id=422218
My preferred solution to this problem (and my default choice for running Selenium Grid as a service) is to use a simple tool called AlwaysUp. It has a free 30 day trial to try it out.
What to do:
Download AlwaysUp
Configure AlwaysUp to start the Selenium Grid node on startup
Configure AlwaysUp to run the Selenium node as a specific user (not the default System user)
This way the the node will run as a service, survive machine restarts and work with the latest version Chrome.
If the user account you use to login to the machine is different from the user account you specify to run the node as a service then you will not see the browsers pop up on the desktop as they are running in a different user session. The end result is that it is almost identical to running as a normal service but gets round the Session 0 issue.
Yeah, you should use NSSM. Important is, that you add your windows account in the "Log on" tab, or any other valid account. If you run your node with the "Local System account" option, you will get the session 0 problem. With a normal user session, the nodes run smoothly invisible in the background :)
we don't use selenium GRID, we were disappointed with its stability. We use a "Jenkins Grid", that is jenkins slaves nodes on various servers.
The slaves are services with the interact with desktop flag. They run as services with NSSM, and the SERVICE_INTERACTIVE_PROCESS flag. Making sure that NoInteractiveProcess is set to 1 (cf https://learn.microsoft.com/en-us/windows/desktop/services/interactive-services).
We don't have the fancy features of the grid (that is balancing according the browser types slots). Instead, we have Jenkins balancing the test jobs using a slave node or another.
Initially we did not use the interact with desktop flag, having browsers to run without "real" display, but the behavior was not very stable (especially with resize commands).
Hope this helps.
As I explained on this thread, I found that using a small paid tool FireDaemon Pro saved me a lot of time from trying to configure NSSM and other free tools.
It works well in the background, and restarts Selenium along with the server, which was my main requirement for running Selenium Standalone Server as a Windows Service.
This free tool would probably do it:
http://yajsw.sourceforge.net/
For that to work, you need a wrapper.conf file and a script to run the YAJSW wrapper. I takes time to read the documentation, but it is a free solution.
I wrote an example shared here, that installs JBoss7 as a Windows service.
Of course, you can simplify my example by a lot.
I am currently attempting to deploy an app to a Windows 10 tablet running the Creator's Update, over my local network. When I select remote machine and enter my debug settings, I can discover the tablet on my network, and get its address and Authentication mode automatically.
However, when I try to deploy, I get this error:
DEP6957 : Failed to connect to device using Universal Authentication. Please verify the correct remote authentication mode is specified in the project debug settings. 0x8007274C: The network event being waited on triggered an error.
As far as I can tell from the documentation that I've read, this process should be more or less plug and play since the Creator's Update, can anyone explain what I might be doing wrong, or what might be going wrong?
Listed here are my debug settings currently in use.
Update: Since its not the solution I was looking for, I'm not adding it as an answer, but if anyone comes across this looking for a fix and no one has suggested one, the way I ended up working through this is just downloading the remote debugger to the tablet and running the old method for C# apps. I never did find out why the UWP method didn't work.
Back on Windows 8.x we had a thing called LoopbackExempt that allowed Windows Store Apps to communicate with the local system for development purposes.
This appears to be still present on Windows 10 for UWP apps.
However, adding an exempt does not work (my apps are still not able to communicate with the localhost).
Doing a CheckNetIsolation does not yield and results:
PS C:\WINDOWS\system32> CheckNetIsolation Debug -n=5bd19b2a-6c63-4dd4-9505-d13f72e46189_ggxdvrfmnj0tt
Network Isolation Debug Session started.
Reproduce your scenario, then press Ctrl-C when done.
Collecting Logs.....
Summary Report
Network Capabilities Status
InternetClient Not Used and Insecure
Detailed Traffic Report
InternetClient Not Used and Insecure
Did they change anything regarding the isolation for UWP? The article to enable the loopback exempt still refers to Windows 8.1?
Thanks in advance!
Just a heads up: the issue no longer exists and was probably a bug in the preview version.
Visual Studio now automatically enables loopback when running a project in the debugger.
I just try to understand the Google update service (aka Omaha) and can't find any information about how Omaha updates Chrome without the UAC Prompt?! Or without any Administrator privileges.
I am looking for a way to lunch a update service that can Update a Application in the Program folder (without UAC / Administrator privileges) just like Omaha does, but i can't find any documentation regarding that topic. Tried browsing the source code a bit thought but i couldn't find anything that helps.
In fact only the Installation should require Administrator Rights, but the update should not.
Any "easy" way to achieve this in C#?
Chrome installs a Windows Service, which is always running and preforms the update. The service runs as SYSTEM and so can perform the update without UAC prompt.
See:
https://support.google.com/installer/answer/98805?hl=en
http://omaha.googlecode.com/svn/wiki/OmahaOverview.html (Execution model section)
I found this nice snippet of code online:
rkApp = Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
Which runs great but alas on windows 7 and vista I suspect, it crashes cause it doesn't have permission to write there.
So then I research (on stackoverflow of course) how to avoid this, quickest method:
rkApp = Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
Simple enough! Though there is two issues remaining. One is with both methods (on a XP Box that is), the program thinks its relative path is somewhere in the C:\windows folder now...so I.e. it won't find my path relative help files etc. The second issue is, on windows 7, my program won't startup until I log in. I want it to start up in the background if possible before anyone logs in.
Its a simple .exe that hangs out in the systray when its running. I didn't want to create this monstrosity of an installer to get around these admin and pathing issues.
I Think I would have to create it as a service (no clue how to do that) to get it to start up when the machine reboots before anyone logs in. Secondly to do that I am sure I have to figure out the admin privileges, and since I don't want to have to approve the program to run every time it starts up it sounds like I would have to figure out its admin privileges during install time, but alas no installer.
So just curious what routes I might take to get this to work. I can even suffer it coming up only after when the user logs in, but my current methods that work this way really screw up the pathing of my program since it tries to write stuff out to a new directory (not the one I originally started the EXE from). Etc...and I have no clue how to go about fixing that pathing issue.
It sounds like you need two programs here.
You can't have an application run in the system tray and run prior to login. The system tray doesn't "exist" until the user logs in and has a valid desktop.
The normal way to handle this is to make two programs. First, create a windows service that does the bulk of your work. This will run on startup, and be independent of any user logins.
Then, make a user mode application which uses IPC to communicate with the service. This can run on login, and "talk" to the service remotely, thereby providing your system tray requirements.
If you want your program to start as a service before anyone logs on, then it's going to need to be installed and run as an admin user. There's not getting round this fact.
There's a Microsoft Knowledge Base article on creating a service which should get you started.
There's a project template for a Windows Service installed by default in Visual Studio 2008:
"File > New > Project > Visual C# > Windows > Windows Service"