private static void Main()
{
// Uncomment this to suppress the default sample metrics.
//Metrics.SuppressDefaultMetrics();
// Replace the first line with an appropriate type of tester to run different manual tests.
var tester = new MetricPusherTester();
//var tester = new KestrelMetricServerTester();
//var tester = new AspNetCoreMiddlewareTester();
//var tester = new MetricServerTester();
// For testing Kestrel metric server with HTTPS, you need at least a self-signed certificate (one included here)
// and the matching domain pointed to 127.0.0.1 (e.g. hardcoded in the PCs hosts file) and you also need to
// import this certificate into your Trusted Root Certification Authorities certificate store to trust it.
//var certificate = new X509Certificate2("prometheus-net.test.pfx", "prometheus-net.test");
//var tester = new KestrelMetricServerTester("prometheus-net.test", certificate);
tester.OnStart();
var metricServer = tester.InitializeMetricServer();
metricServer?.Start();
var counter = Metrics.CreateCounter("myCounter", "help text", new CounterConfiguration
{
LabelNames = new[] { "method", "endpoint" }
});
counter.WithLabels("GET", "/").Inc();
counter.WithLabels("POST", "/cancel").Inc();
Metrics.CreateCounter("always_zero", "This counter is always zero but still needs to be present in the output!");
var gauge = Metrics.CreateGauge("gauge", "help text");
gauge.Inc(3.4);
gauge.Dec(2.1);
gauge.Set(5.3);
// As the initial value is suppressed and a new one never assigned, this one never shows up in the export.
Metrics.CreateGauge("should_not_show_up", "", new GaugeConfiguration
{
SuppressInitialValue = true
});
var hist = Metrics.CreateHistogram("myHistogram", "help text", new HistogramConfiguration
{
Buckets = new[] { 0, 0.2, 0.4, 0.6, 0.8, 0.9 }
});
hist.Observe(0.4);
var timedHistogram = Metrics.CreateHistogram("myTimedHistogram", "help text", new HistogramConfiguration
{
Buckets = new[] { 0, 0.2, 0.4, 0.6, 0.8, 0.9 }
});
var latestGauge = Metrics.CreateGauge("latestGauge", "Reports the latest cycle time");
var summary = Metrics.CreateSummary("mySummary", "help text");
summary.Observe(5.3);
// Example implementation of updating values before every collection.
var collectionCount = Metrics.CreateCounter("beforecollect_example", "This counter is incremented before every data collection.");
// Synchronous callbacks should be instantaneous, to avoid causing delays in the pipeline.
Metrics.DefaultRegistry.AddBeforeCollectCallback(() => collectionCount.Inc());
var googlePageBytes = Metrics.CreateCounter("beforecollect_async_example", "This counter is incremented before every data collection, but asynchronously.");
// Callbacks can also be asynchronous. It is fine for these to take a bit more time.
// For example, you can make an asynchronous HTTP request to a remote system in such a callback.
var httpClient = new HttpClient();
Metrics.DefaultRegistry.AddBeforeCollectCallback(async(cancel) =>
{
// Probe a remote system.
var response = await httpClient.GetAsync("https://google.com", cancel);
// Increase a counter by however many bytes we loaded.
googlePageBytes.Inc(response.Content.Headers.ContentLength ?? 0);
});
// Uncomment this to test deliberately causing collections to fail. This should result in 503 responses.
// With MetricPusherTester you might get a 1st push already before it fails but after that it should stop pushing.
//Metrics.DefaultRegistry.AddBeforeCollectCallback(() => throw new ScrapeFailedException());
#if NETCOREAPP
var diagnosticSourceRegistration = DiagnosticSourceAdapter.StartListening();
#endif
var cts = new CancellationTokenSource();
var random = new Random();
// Update metrics on a regular interval until told to stop.
var updateInterval = TimeSpan.FromSeconds(0.5);
var updateTask = Task.Factory.StartNew(async delegate
{
while (!cts.IsCancellationRequested)
{
using (latestGauge.NewTimer())
using (timedHistogram.NewTimer())
{
var duration = Stopwatch.StartNew();
counter.Inc();
counter.Labels("GET", "/").Inc(2);
gauge.Set(random.NextDouble() + 2);
hist.Observe(random.NextDouble());
summary.Observe(random.NextDouble());
try
{
tester.OnTimeToObserveMetrics();
}
catch (Exception ex)
{
Console.Error.WriteLine(ex);
}
var sleepTime = updateInterval - duration.Elapsed;
if (sleepTime > TimeSpan.Zero)
{
await Task.Delay(sleepTime, cts.Token);
}
}
}
}).Result;
Console.WriteLine("Press enter to stop metricServer");
Console.ReadLine();
cts.Cancel();
try
{
updateTask.GetAwaiter().GetResult();
}
catch (OperationCanceledException)
{
}
metricServer?.StopAsync().GetAwaiter().GetResult();
tester.OnEnd();
Console.WriteLine("Press enter to stop tester");
Console.ReadLine();
}
static void Main(string[] args)
{
// Replace the first line with an appropriate type of tester to run different manual tests.
var tester = new MetricPusherTester();
// For testing Kestrel metric server with HTTPS, you need at least a self-signed certificate (one included here)
// and the matching domain pointed to 127.0.0.1 (e.g. hardcoded in the PCs hosts file) and you also need to
// import this certificate into your Trusted Root Certification Authorities certificate store to trust it.
//var certificate = new X509Certificate2("prometheus-net.test.pfx", "prometheus-net.test");
//var tester = new KestrelMetricServerTester("prometheus-net.test", certificate);
tester.OnStart();
var metricServer = tester.InitializeMetricServer();
metricServer?.Start();
var counter = Metrics.CreateCounter("myCounter", "help text", labelNames: new[] { "method", "endpoint" });
counter.Labels("GET", "/").Inc();
counter.Labels("POST", "/cancel").Inc();
var zeroValue = Metrics.CreateCounter("always_zero", "This counter is always zero but still needs to be present in the output!");
var gauge = Metrics.CreateGauge("gauge", "help text");
gauge.Inc(3.4);
gauge.Dec(2.1);
gauge.Set(5.3);
var hist = Metrics.CreateHistogram("myHistogram", "help text", buckets: new[] { 0, 0.2, 0.4, 0.6, 0.8, 0.9 });
hist.Observe(0.4);
var summary = Metrics.CreateSummary("mySummary", "help text");
summary.Observe(5.3);
// Exmaple implementation of a custom collector.
DefaultCollectorRegistry.Instance.GetOrAdd(new ExternalDataCollector());
// Example implementation of on-demand collection.
DefaultCollectorRegistry.Instance.RegisterOnDemandCollectors(new OnDemandCollection());
// Uncomment this to test deliberately causing collections to fail. This should result in 503 responses.
// With MetricPusherTester you might get a 1st push already before it fails but after that it should stop pushing.
//DefaultCollectorRegistry.Instance.RegisterOnDemandCollectors(new AlwaysFailingOnDemandCollector());
var cts = new CancellationTokenSource();
var random = new Random();
// Update metrics on a regular interval until told to stop.
var updateInterval = TimeSpan.FromSeconds(0.5);
var updateTask = Task.Factory.StartNew(async delegate
{
while (!cts.IsCancellationRequested)
{
var duration = Stopwatch.StartNew();
counter.Inc();
counter.Labels("GET", "/").Inc(2);
gauge.Set(random.NextDouble() + 2);
hist.Observe(random.NextDouble());
summary.Observe(random.NextDouble());
try
{
tester.OnTimeToObserveMetrics();
}
catch (Exception ex)
{
Console.Error.WriteLine(ex);
}
var sleepTime = updateInterval - duration.Elapsed;
if (sleepTime > TimeSpan.Zero)
{
await Task.Delay(sleepTime, cts.Token);
}
}
}).Result;
Console.WriteLine("Press enter to stop metricServer");
Console.ReadLine();
cts.Cancel();
try
{
updateTask.GetAwaiter().GetResult();
}
catch (OperationCanceledException)
{
}
metricServer?.StopAsync().GetAwaiter().GetResult();
tester.OnEnd();
Console.WriteLine("Press enter to stop tester");
Console.ReadLine();
}