Question

I cant figure out how to proceed the best way with this problem.

Right now I have a windows service which only task is to gather data from a database with a specific DSN and then send out an email if the data is valid. The service contains a timer which ticks every 5 minuts and performs the tasks above.

Now I need to re-write the windows service to be able to run on more than 1 DSN.
I was thinking of making several threads inside the windows service and then again have a seperat timer inside each thread.
Is this a good idea and how can this be done? I want to avoid having a windows service for each DSN.

Ill try to draw it if I dont make any sense

                             Windows Service

Thread1(DSN1)—————————–Thread2(DSN2)———————-Thread3(DSN3)
Timer(ticks every X minuts)—————–Timer(same)————————-Timer(same)
Logic()———————————————Logic———————————Logic()

Hope my problem makes sense 🙂

Answer 1

As far as I Know each timer represents a thread on its own. Knowing this, I would try to dynamically create timer objects for each given dsn.

public partial class Service1 : ServiceBase
{
    public Service1()
    {
        InitializeComponent();
    }

    private List<GetDataFromDSN> list = null;
    protected override void OnStart(string[] args)
    {
        list = new List<GetDataFromDSN>();
        // assume args contains your given dsn values
        foreach (string dsn in args)
        {
            GetDataFromDSN newObj = new GetDataFromDSN();
            newObj.DSN = dsn;
            list.Add(newObj);
            newObj.Start();
        }
    }
}

public class GetDataFromDSN
{
    public string DSN { get; set; }
    private Timer timer = null;
    private double interval = 1000*60*5; // 5 minutes interval
    public GetDataFromDSN()
    {
        // init your object
        timer = new Timer(interval);
        timer.Elapsed +=new ElapsedEventHandler(timer_Elapsed);
    }
    private void timer_Elapsed(object sender, ElapsedEventArgs e)
    {
        // do what ever you want
    }
    public void Start() // or even make timer public
    {
        timer.Start();
    }
    public void Stop()
    {
        timer.Stop();
    }
}