I'm running two Perl scripts in parallel in Jenkins
some shell commands
perl script 1 &
perl script 2 &
wait
some more shell commands
If one of the perl scripts fail in the middle of the execution , the job waits until the other script runs (as it is executed in parallel in background).
I want the job to stop as soon as one of the script fails and not waste time by completing the execution of other script.
Please help.
You set up a signal handler for SIGCHLD, which is a signal that is always delivered to the parent process when a child exits. I'm not aware of a mechanism to see which child process exited, but you can save the subprocess process identifiers and just kill both of them when you receive SIGCHLD:
some shell commands
perl script 1 &
pid1=$!
perl script 2 &
pid2=$!
trap "kill $pid1 $pid2" CHLD
wait
some more shell commands
The script above has the downside that it will kill the other script regardless of the exit status of the subprocess. You could in the trap, if you want to, add a check for the exit status. The subprocess could e.g. create some temp file if it succeeds and the trap could check if the file exists.
Typically with Jenkins you would have the parallel steps running as separate jobs (or projects as they are sometimes known) rather than steps in a job. This would then allow the steps to run in parallel across different slave machines and it would keep the output for the jobs in a separate place.
You would then have a controlling job running the other parts.
I like the Multijob plugin for this sort of thing.
There are alternatives which may suit better, such as Build Flow Plugin which uses a DSL to describe the jobs you want to run
Related
I'm aiming to run a Powershell script on the startup on my windows 10. This tutorial has perfectly explained that: https://devblogs.microsoft.com/scripting/use-powershell-to-create-job-that-runs-at-startup/
But I expect the job to keep my script running as my app is listening to some events but when I check the status of the job using the Get-job cmdlet it shows that it's completed. I think that it's treating my script as an asynchronous one and eventually, my doesn't listen to anything. Any idea how can I make it synchronous i.e. keep my script running forever? This is the content of my ps1 file:
C:\Users\m\Desktop\Scripts\Activate.ps1
python C:\Users\m\Desktop\app.py
I have a situation where I want to make the execution of my scripts smarter. I have a set of scripts that execute at a given time, but because sometimes the input files are not posted at the correct times the scripts run into errors and get unexpected results. so one of the solutions I was thinking of is to make the execution of the scripts dependent of each other. Here is what I mean:
script 1 runs at 6 pm
validates that the file is there
if it's there, set a flag
the flag is active so execute script 2 at 9 pm
if it's NOT there, the flag is not set
the flag is not set so script 2 is not executed
Right now script 1 and script 2 are set with the Task Scheduler at those times, I checked the Scheduler for those type of conditions, but didn't find anything.
You can set triggers in Task Scheduler, like when an event happens for basically everything you can see in eventviewer.
I would suggest Write-Eventlog from the script which works on the file, and depending on the result the sched task would get triggerd.
I suggest you to have single script running every N-minutes on single scheduled task via Task Scheduler.
The master script will analyze activities and have all logical conditions those determine when and which external script to run. You can also have flag files.
I have a PowerShell task in my definition that calls another script file on its own which takes care of running several things on my build agent (starts several different processes) - emulators, node.js applications, etc.
Everything is fine up until the moment this step is done and the run continues. All of the above mentioned stuff gets closed with most of the underlying processes killed, thus, any further execution (e.g. tests run) is doomed to fail.
My assumption is that these processes are somehow dependent on the outermost (temporary) script that VSTS generates to process the step.
I tried with the -NoExit switch specified in the arguments list of my script, but to no avail. I've also read somewhere a suggestion to set this by default with a registry key for powershell.exe - still nothing.
The very same workflow was okay in Jenkins. How can I fix this?
These are the tasks I have:
The last PowerShell task calls a specified PowerShell file which calls several others on its own. They ensure some local dependencies and processes needed to start executing the tests, e.g. a running Node.js application (started in a separate console for example and running fine).
When the task is done and it is successful, the last one with the tests would fail because the Node.js application has been shut down as well as anything else that was started within the previous step. It just stops everything. That's why I'm currently running the tests within the same task itself until I find out how to overcome this behavior.
I am not sure how you call the dependencies and applications in your PowerShell script. But I tried with the following command in PowerShell script task to run a Node.js application:
invoke-expression 'cmd /c start powershell -Command {node main.js}'
The application keeps running after the PowerShell script task is passed and finished which should meet your requirement. Refer to this question for details: PowerShell launch script in new instance.
But you need to remember to close the process after the test is finished.
There is the Continue on error option (Control Options section). The build process will be continued if it is true (checked), but the build result will be partially succeeded.
You also can output the error or warning by using PowerShell or VSTS task commands (uncheck Fail on Standard Error option in the Advanced section) and terminate the current PowerShell process by using the exit keyword, for example:
Write-Warning “warning”
Write-Error “error”
Write-Host " ##vso[task.logissue type=warning;]this is the warning"
Write-Host " ##vso[task.logissue type=error;sourcepath=consoleapp/main.cs;linenumber=1;columnnumber=1;code=100;]this is an error "
More information about the VSTS task command, you can refer to: Logging Commands
I want to schedule a job to run every 5 minutes. but the question is that
Is there a way (like creating a crontab) to prevent a job from running, when the previous job has not been completed?
You can write a shell script to start the job only when the job is not already running. Configure the shell script in crontab every 5 minutes. this will ensure that the execution happens only when there is no instance of the job running already. This is how i have done for my cron jobs
Note : make use of ps -ef | grep commands in your shell script to identify if there is a process already running
Let's say I have 5 batch files that run sequentially one after another (executed via the Windows task scheduler on a normal Windows XP PC):
Script1.bat
Script2.bat
Script3.bat
Script4.bat
Script5.bat
Suppose one of the scripts fail (an error condition is detected -- details on how this happens is not important for my question here). How do I stop the other scripts from running if they all run within the task scheduler? For example, if Script1.bat fails, I don't want to run Script2-5.bat. If Script3.bat fails, I don't want to run Script4-5.bat, etc.
I thought about writing a flag value to a temporary file that each script would read from. At the beginning of each script (except for the first one), it will check to see if the flag is valid. The first script would clear out this flag at the beginning each time these set of batch files run.
Surely there is a better way to do this or maybe there is a standard for how to handle this type of situation? Thanks!
Write a master.bat file that conditionally calls each of the scripts in sequence. Then schedule the master instead of directly scheduling the 5 scripts.
#echo off
call Script1.bat
if %errorlevel%==0 call Script2.bat
if %errorlevel%==0 call Script3.bat
if %errorlevel%==0 call Script4.bat
if %errorlevel%==0 call Script5.bat