/// <summary>
/// Create HTTP endpoint where metrics will be available in various formats:
/// GET / => visualization application
/// GET /json => metrics serialized as JSON
/// GET /text => metrics in human readable text format
/// </summary>
/// <param name="httpUriPrefix">prefix where to start HTTP endpoint</param>
public MetricsConfig WithHttpEndpoint(string httpUriPrefix)
{
if (this.isDisabled)
{
return this;
}
using (this.listener) { }
this.listener = new MetricsHttpListener(httpUriPrefix, this.Registry, this.healthStatus);
this.listener.Start();
return this;
}
public static Task <MetricsHttpListener> StartHttpListenerAsync(string httpUriPrefix, MetricsDataProvider dataProvider,
Func <HealthStatus> healthStatus, CancellationToken token, int maxRetries = 1)
{
return(Task.Factory.StartNew(async() =>
{
MetricsHttpListener listener = null;
var remainingRetries = maxRetries;
do
{
try
{
listener = new MetricsHttpListener(httpUriPrefix, dataProvider, healthStatus, token);
listener.Start();
if (remainingRetries != maxRetries)
{
log.InfoFormat("HttpListener started successfully after {0} retries", maxRetries - remainingRetries);
}
remainingRetries = 0;
}
catch (Exception x)
{
using (listener) { }
listener = null;
remainingRetries--;
if (remainingRetries > 0)
{
log.WarnException("Unable to start HTTP Listener. Sleeping for {0} sec and retrying {1} more times", x, maxRetries - remainingRetries, remainingRetries);
await Task.Delay(1000 * (maxRetries - remainingRetries), token).ConfigureAwait(false);
}
else
{
MetricsErrorHandler.Handle(x, $"Unable to start HTTP Listener. Retried {maxRetries} times, giving up...");
}
}
} while (remainingRetries > 0);
return listener;
}, token).Unwrap());
}
public void Dispose()
{
using (this.listener) { }
this.listener = null;
}
