/// <summary>
/// Stops the service immediately, terminating any user activity.
/// </summary>
public void Stop()
{
lock (syncLock)
{
if (state == ServiceState.Stopped)
{
return;
}
SysLog.LogInformation("Heartbeat Service Stop");
SysLog.Flush();
base.Close();
state = ServiceState.Stopped;
}
if (handler != null)
{
handler.Stop();
handler = null;
}
if (router != null)
{
router.Stop();
router = null;
}
Program.PerfCounters.Zero();
}
private ServiceState state; // Current service state
/// <summary>
/// Constructor.
/// </summary>
public AppService()
{
this.router = null;
this.handler = null;
this.state = ServiceState.Stopped;
// Prepare the service to accept remote ServiceControl commands.
base.Open();
}
/// <summary>
/// Handles the performance counter installation if they don't
/// already exist.
/// </summary>
/// <returns>The application's <see cref="PerfCounterSet" />.</returns>
public static PerfCounterSet InstallPerfCounters()
{
bool exists = PerformanceCounterCategory.Exists(Const.HeartbeatPerf);
PerfCounterSet perfCounters;
perfCounters = new PerfCounterSet(false, true, Const.HeartbeatPerf, Const.HeartbeatName);
if (!exists)
{
HeartbeatHandler.InstallPerfCounters(perfCounters, null);
perfCounters.Install();
}
return(perfCounters);
}
/// <summary>
/// Starts the service, associating it with an <see cref="IServiceHost" /> instance.
/// </summary>
/// <param name="serviceHost">The service user interface.</param>
/// <param name="args">Command line arguments.</param>
public void Start(IServiceHost serviceHost, string[] args)
{
lock (syncLock)
{
if (router != null)
{
return; // Already started
}
// Global initialization
NetTrace.Start();
Program.Config = new Config("LillTek.Datacenter.HeartbeatService");
Program.InstallPerfCounters();
// Service initialization
this.serviceHost = serviceHost;
SysLog.LogInformation("Heartbeat Service v{0} Start", Helper.GetVersionString());
try
{
router = new LeafRouter();
router.Start();
handler = new HeartbeatHandler();
handler.Start(router, null, Program.PerfCounters, null);
state = ServiceState.Running;
}
catch (Exception e)
{
if (handler != null)
{
handler.Stop();
handler = null;
}
if (router != null)
{
router.Stop();
router = null;
}
SysLog.LogException(e);
throw;
}
}
}
public void HeartbeatHandler_SingleService()
{
// Configure a heartbeart service to monitor a single URI and verify
// that it can detect health and failure.
HeartbeatHandler handler = null;
HttpServer httpServer = null;
const string cfg = @"
§ion LillTek.Datacenter.HeartbeatService
NetworkBinding = ANY:HTTP-HEARTBEAT
Service[-] = http://testservice01.lilltek.com:666/Heartbeat.aspx?global=0
PollInterval = 1s
BkInterval = 1s
&endsection
";
try
{
Config.SetConfig(cfg.Replace('&', '#'));
// Initialize the health status dictionary and crank up a HTTP listerner
// to simulate target services.
host2Health = new Dictionary <string, bool>(StringComparer.OrdinalIgnoreCase);
host2Health["testservice01.lilltek.com"] = true;
httpServer = new HttpServer(new IPEndPoint[] { new IPEndPoint(IPAddress.Any, 666) }, new IHttpModule[] { this }, 10, 10, 8196);
httpServer.Start();
// Start the heartbeat handler
handler = new HeartbeatHandler();
handler.Start(null, null, null, null);
// Give the service a chance to ping the test a few times and then
// make a request to the heartbeat handler to verify that it indicates
// that the server is healthy.
Thread.Sleep(3000);
Assert.IsTrue(GetHealth());
// Now indicate that the target service is unhealthy, give the heartbeat
// handler a chance to ping the service, and verify that it determined
// the server is unhealthy.
host2Health["testservice01.lilltek.com"] = false;
Thread.Sleep(3000);
Assert.IsFalse(GetHealth());
// Now indicate that the target service is healthy, give the heartbeat
// handler a chance to ping the service, and verify that it determined
// the server is healthy.
host2Health["testservice01.lilltek.com"] = true;
Thread.Sleep(3000);
Assert.IsTrue(GetHealth());
// Stop the simulated target HTTP server and verify that the handler
// detects the failure.
httpServer.Stop();
httpServer = null;
Thread.Sleep(3000);
Assert.IsFalse(GetHealth());
}
finally
{
Config.SetConfig(null);
if (handler != null)
{
handler.Stop();
}
if (httpServer != null)
{
httpServer.Stop();
httpServer = null;
}
}
}
