I'd like to move my scheduled tasks into workflows so I can better monitor their execution. Currently I'm using a Window's scheduled task to call a web service that starts the process. Is there a facility that you use to schedule execution of a sequence so that it occurs every N minutes?
My optimal solution would:
Easy to configure
Provide useful feedback on errors
Be 'fire and forget'
PS - Trying out AppFabric for Windows Server if that adds any options.
The most straightforward way I know of would be to make an executable for each workflow (could be console or windows app), and have it host the workflow through code.
This way you can continue to use scheduled tasks to manage the tasks, the main issue is feedback/monitoring the process. For this you could output to console, write to the event log, or even have a more advanced visualisation with a windows app - although you'd have to write this yourself (or google for something!). This MS Workflow Monitoring sample might be of interest, haven't used it myself.
Similar deal with errors, although writing to the event log would be the normal course of action in this case.
I'm not aware of any other hosts for WF, aside from things like Dynamics CRM, but that won't help you with what you're trying to do.
You need to use a scheduler. Either roll your own, use AppFabic as mentioned or use Quartz.NET:
http://quartznet.sourceforge.net/
If you use Quartz, it's either roll your own service host or use the ready-made one and configure it using xml. I rolled my own and it worked fine.
Autorun is another free option... http://autorun.codeplex.com/
Related
I use Alfresco Community 5.2 and my need is to perform some work when one of the default Alfresco's workflow is started.
I could override all the workflows definitions, but I wonder if there is a better and quicker way to do that. The perfect would be a behavior which triggers when a workflow is started.
Is there something like that ?
Any other approach is accepted. Thanks.
There isn't anything similar to a behavior for workflows that I know of, although if your workflows will always have documents attached you could consider binding a behavior to the workflow package type (I don't recall off-hand what that type is--it might just be cm:folder which wouldn't be that useful).
This is kind of a hack suggestion, but you could implement a quartz job that would run every 30 seconds or every minute or so that would use the workflow service to check to see if any new workflows have started since the last check. If so, your code could be notified and passed the workflow ID, process ID, etc.
The straightforward solution is as you suggested in your original post--just modify the out-of-the-box processes with a task listener that fires when the workflow starts.
Following Jeff suggestion, and this tutorial, I managed to implement a task creation/completion listener and do my logic inside those blocks, resolving the problem.
I am using quartz to schedule jobs to be executed daily as a part of a much larger web application. However, after a couple of days, the administrator would like to stop the execution of a particular job (maybe because it is no longer needed). How do I go about doing this? I read the api docs for the Scheduler and it has a method called interrupt(JobKey jobkey) but that method would work only with the same instance of the scheduler that was used to schedule the job.
interrupt(JobKey jobKey)
Request the interruption, within this Scheduler instance, of all
currently executing instances of the identified Job, which must be an
implementor of the InterruptableJob interface.
Is there anyway of getting the instance of an existing scheduler? Or maybe use singletons?
Should definitely use a singleton instance of your scheduler. I recommend the use of an IoC container to manage this in a clean and efficient way.
I need to execute a call to a particular method daily or more, considering that the app may and the machine may reboot.
I saw examples where they just put the thread to sleep but I need persistance, managing system rebooting.
I have to be sure that if I switch off my machine when I reboot it reprises task execution.
I found schedulers as cron4j and quartz but don't get if it's possible, and if it is, how to do that.
With Quartz you will only need to configure it with a persistent job store implementation and that is pretty much all there is to it. I suggest that you read through the Quartz scheduler tutorial, especially the chapter that describes Quartz job stores.
I have several perl scripts for data download, validation, database upload etc. I need to write a job controller who can run these scripts in specified manner.
Is there any job controller module in perl?
There are a bunch of options and elements to what you're looking for.
Here for instance is a "job persistence engine"
http://metacpan.org/pod/Garivini
What I think you want might be more comprehensive. You could go big with something like "bamboo" which is a continuous integration/build system. There are several of those if you want to go down that route:
http://en.wikipedia.org/wiki/Continuous_integration
Or you could start with something like RabbitMQ, which bills itself as a message queuing system but has the ability to restart failed jobs and execute things in order, so it has some resilience built in, but you the actual job control software (what watches the queue and executes events?) might need to be written by you, using the Net::RabbitMQ module. I'm not sure.
http://metacpan.org/pod/Net::RabbitMQ
Here is a (Ruby) example of using RabbitMQ to manage job queuing.
How do I trigger a job when another completes?
I'm developing some Workflow 4 activities that will continuously loop and do some work. For example, one may watch an RSS feed and execute some steps as new items are added. I would like to be able to stop and restart this process cleanly (ie, in a windows service or Azure Worker Role). Currently, I have a While loop with an expression that always resolves to true, and just let the instance die when the app closes. But it seems like this is not a very clean way to stop the workflow.
How should I stop and restart the workflow?
The exact system depends a bit in the way you host your workflow but I am assuming you are using the WorkflowApplication. In that case simple option is to use the WorkflowApplication which has a Cancel method you can use to cancel execution of the workflow. You can also create a bookmarked activity and resume a stop bookmark or something similar but that might be overkill.