My good ladies and gentlemen, I recently had my first go at Worker services in .Net Core 3.1, and only the second go at Windows services in general (first one was made in .Net Framework and works fine to this day). If anyone could maybe shed some light at what I'm missing in the example that I will provide that would be great.
So, to keep it simple, my problem is this: My supposed long (forever) running Worker service unexpectedly stops doing work at an arbitrary time of day, but still is shown as "Running" in service manager (that's probably how Windows deals with services). It doesn't necessarily have to be every day, but it stops doing work every now and then until I manually stop it and then restart it in Service Manager.
I have also stumbled upon this question which seemed to deal with my problem, but even after completely wrapping all of my service's code blocks in try-catchs, even on top-level, I still get nothing registered in my Log table, or even in the file I set up to write in if my DB connection fails. Service seems to just stop calling ExecuteAsync() method.
Ok here's how my code's logically structured, I have excluded implementation and I'm just showing what happens until DoWork is called:
public class Worker : BackgroundService
{
private readonly IConfiguration _configuration;
public Worker(IConfiguration configuration)
{
_configuration = configuration;
}
public override Task StartAsync(CancellationToken cancellationToken)
{
return base.StartAsync(cancellationToken);
}
protected override async Task ExecuteAsync(CancellationToken stoppingToken)
{
try
{
while (true)
{
try //paranoid try-catch
{
await DoWork();
await Task.Delay(TimeSpan.FromSeconds(45), stoppingToken);
}
catch (Exception e)
{
await Log(e, customMessage: "Proccess failed at top level.");
}
}
}
catch (Exception e)
{
await Log(e, customMessage: "Proccess failed at topmost level.");
}
}
private async Task DoWork()
{
try
{
}
catch (Exception e)
{
await Log(e);
}
}
public async Task Log(Exception e, string user = null, string emailID = null, string customMessage = null)
{
}
}
As you can see, I am not handling cancellation, as in the question I linked above. Now that I think about it maybe I should, and something is inadvertently sending cancellation? The reason I didn't is because I'm not sure what events exactly signal the cancellation. Only the manual stopping of service, or something else maybe? And if it is the cancellation that was sent that caused my service to stop doing work, shouldn't it also stop my service from running?
Btw I just tested cancellation on dummy service which implements my logic with while(true) and it catches the stopping exception, even though it's a bit awkward, as it catches it and logs it multiple times before stopping, so I presume it may not be the cancellation token that is causing my DoWork not to fire.
