/// <summary>
/// Method registers application instance to eureka service with ability to provide additional healthcheck callback.
/// </summary>
/// <param name="healthCheck">External function performing additional validation for the service health.
/// Function must return boolean value indicating the service health.
/// If FALSE value returned, then no HEALTHY heartbeat is being sent.</param>
/// <returns>Returns boolean indicator of success.</returns>
public bool RegisterApplicationInstance(Func <bool> healthCheck)
{
bool result = false;
try
{
Trace.TraceInformation("Registering instance with EUREKA service...");
result = EurekaClientExecutor.Wrap(this.eureka).ExecuteWithRetry(() => this.eureka.Register(DataCenterMetadata), this.AppConfig.EurekaServiceUrls);
if (result)
{
Trace.TraceInformation("Initializing instance heartbeat...");
this.heartbeat = new HeartbeatObserver(this.eureka, this.DataCenterMetadata, this.AppConfig.EurekaServiceUrls);
if (healthCheck != null)
{
this.heartbeat.OnHealthCheck = healthCheck;
}
this.heartbeat.InitializeAndStartTimer();
}
}
catch (Exception ex)
{
if (this.eureka != null)
{
EurekaClientExecutor.Wrap(this.eureka).ExecuteWithRetry(() => this.eureka.Unregister(DataCenterMetadata), this.AppConfig.EurekaServiceUrls);
}
if (this.heartbeat != null)
{
this.heartbeat.StopTimer();
}
throw ex;
}
return(result);
}
/// <summary>
/// Method unregisters application instance from eureka service.
/// </summary>
/// <returns>Returns boolean indicator of success.</returns>
public bool UnregisterApplicationInstance()
{
bool result = EurekaClientExecutor.Wrap(this.eureka).ExecuteWithRetry(() => this.eureka.Unregister(DataCenterMetadata), this.AppConfig.EurekaServiceUrls);
if (this.heartbeat != null)
{
this.heartbeat.StopTimer();
}
return(result);
}
/// <summary>
/// Method takes application instance back to service at the eureka service.
/// </summary>
/// <returns>Returns boolean indicator of success.</returns>
public bool PutInstanceToService()
{
bool result = EurekaClientExecutor.Wrap(this.eureka).ExecuteWithRetry(() => this.eureka.PutInstanceToService(DataCenterMetadata), this.AppConfig.EurekaServiceUrls);
if (this.heartbeat != null)
{
this.heartbeat.StartTimer();
}
return(result);
}
private void TimerWorker(object sender, System.Timers.ElapsedEventArgs e)
{
try
{
if (this.OnHealthCheck != null)
{
if (!this.OnHealthCheck())
{
timer.Start();
return;
}
}
EurekaClientExecutor.Wrap(this.eureka).ExecuteWithRetry(() => this.eureka.SendHeartbeat(DataCenterMetadata), this.EurekaServiceUrls);
timer.Start();
}
catch (Exception ex)
{
Trace.TraceError("Exception: " + ex.ToString());
}
}
