Sometimes someone writes a post that makes you say, “Oh shit!”. For example,
Jon Galloway writes that writing a windows service just to run a scheduled process is a bad idea.
And he presents a very nice case. Nice enough that I take back the times I have condescendingly said that Windows Services are easy to write in .NET. I probably should look through some of the services I have written in the past. I know of one I could easily convert to a console app and gain functionality.
However, I think the decision sometimes isn’t so easy as that. One service I have written in the past is a Socket Server that takes in encrypted connections and communicates back with the client. Now that obviously needs to run all the time and is best served as a Windows Service. The problem then was since I had written the Windows Service code to be generalized, I was able to implement many other services very quickly, even ones with timers that ran on a schedule.
However, the most challenging ones to write, happened to be the ones that ran on a schedule, since the scheduling requirements kept changing and I realized I was going down the path to implementing...well...the Windows Task Scheduler.
In general, I think Jon’s right. If all you are doing is running a scheduled task, use Windows Task Scheduler until you reach the point that your system’s need are no longer met by the scheduler. This follows the principle of doing only what is necessary and implementing the simplest solution that works.
In a conversation, Jon mentioned that a lot of developers perceive Windows Services to be a more “professional” solution than task scheduling a console app. But one way to think of a service is an application that responds to requests and system events, not necessarily a scheduled task. So to satisfy both camps you could consider creating a service that takes in requests, and a scheduled task to make the requests. For example, a service might have a file system watcher active and a scheduled task might write the file. I don’t suggest adding all this complexity to something that can be very simple.
For me, I also like writing windows services because I have a system for quickly creating installation packages very quickly. What I need to do is spend some time creating an installer task for setting up a windows task scheduler job. That way I can do the same for a scheduled console app.