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Aaronontheweb/TcpInstrumentation.cs

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.NET OpenTelemetry Metrics for TCP Listeners
Raw
dashboard.json
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Raw
TcpInstrumentation.cs
// -----------------------------------------------------------------------
// <copyright file="TcpInstrumentation.cs" company="Petabridge, LLC">
// Copyright (C) 2024 - 2024 Petabridge, LLC <https://petabridge.com>
// </copyright>
// -----------------------------------------------------------------------
using System.Net;
using System.Net.NetworkInformation;
using OpenTelemetry.Metrics;
using static OpenTelemetry.TcpInstrumentation.TcpInstrumentationMeter;
namespace OpenTelemetry.TcpInstrumentation;
/// <summary>
/// Publicly available instrumentation code for tracking TCP connections and listeners
/// </summary>
public static class TcpInstrumentation
{
/// <summary>
/// Subscribe to TCP connection and listener events and track them using OpenTelemetry metrics.
/// </summary>
/// <param name="builder"></param>
/// <param name="onlyCareAboutTheseEndpoints">Optional. When populated, we will only report
/// about activity involving these endpoints.</param>
/// <remarks>
/// This method will automatically start tracking TCP connection and listener activity in the background - captures
/// everything happening in the current environment.
/// </remarks>
public static MeterProviderBuilder AddTcpConnectionInstrumentation(this MeterProviderBuilder builder,
IPEndPoint[]? onlyCareAboutTheseEndpoints = null)
{
builder.AddMeter(MeterName);
// these will just run in the background
var (connectionsTracker, tcpListenersTracker) = TrackTcpActivity(KeepConnectionData, KeepListenerData);
return builder;
bool KeepListenerData(IPEndPoint endpoint)
{
if (onlyCareAboutTheseEndpoints is null || onlyCareAboutTheseEndpoints.Length == 0) return true;
foreach (var caredAboutEndpoint in onlyCareAboutTheseEndpoints)
{
if (caredAboutEndpoint.Equals(endpoint)) return true;
}
return false;
}
bool KeepConnectionData(TcpConnectionInformation connection)
{
if (onlyCareAboutTheseEndpoints is null || onlyCareAboutTheseEndpoints.Length == 0) return true;
foreach (var endpoint in onlyCareAboutTheseEndpoints)
{
if (connection.LocalEndPoint.Equals(endpoint) || connection.RemoteEndPoint.Equals(endpoint)) return true;
}
return false;
}
}
}
Raw
TcpInstrumentationMeter.cs
using System.Diagnostics;
using System.Diagnostics.Metrics;
using System.Net;
using System.Net.NetworkInformation;
namespace OpenTelemetry.TcpInstrumentation;
/// <summary>
/// INTERNAL API - private implementation details for tracking TCP connections and listeners
/// </summary>
internal static class TcpInstrumentationMeter
{
public const string MeterName = "OpenTelemetry.TcpInstrumentation";
public static readonly Meter Meter = new Meter(MeterName);
public const string ActiveTcpConnectionsName = "tcp.connections.active";
public const string TcpConnectionsUnit = "tcp_connections";
public const string ActiveTcpListenersName = "tcp.listeners.active";
public const string TcpListenersUnit = "tcp_listeners";
private static readonly Predicate<TcpConnectionInformation> DefaultTcpConnectionKeepFn = information => true;
private static readonly Predicate<IPEndPoint> DefaultListeningEndpointKeepFn = ip => true;
public static (ObservableGauge<int> connectionsTracker, ObservableGauge<int> tcpListenersTracker) TrackTcpActivity(
Predicate<TcpConnectionInformation>? keepConnectionData = null,
Predicate<IPEndPoint>? keepListenerData = null)
{
var connectionsTracker = TrackActiveTcpConnections(ActiveTcpConnectionsName, "Active TCP Connections", keepData: keepConnectionData);
var tcpListenersTracker = TrackActiveTcpListeners(ActiveTcpListenersName, "Active TCP Listeners", keepData:keepListenerData);
return (connectionsTracker, tcpListenersTracker);
}
public static ObservableGauge<int> TrackActiveTcpConnections(string metricName, string description,
string units = TcpConnectionsUnit, Predicate<TcpConnectionInformation>? keepData = null)
=> Meter.CreateObservableGauge<int>(metricName,
() =>
{
keepData ??= DefaultTcpConnectionKeepFn;
var rawMeasurements = new Dictionary<TcpState, int>();
var realMeasurements = Array.Empty<Measurement<int>>();
IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
TcpConnectionInformation[] connections = properties.GetActiveTcpConnections();
// for each connection, if the connection is to be kept, add it to the measurements
foreach (var connection in connections)
if (keepData(connection))
{
rawMeasurements.TryAdd(connection.State, 0);
rawMeasurements[connection.State]++;
}
// bail out early if we have no data
if (rawMeasurements.Count == 0)
return realMeasurements;
realMeasurements = new Measurement<int>[rawMeasurements.Count];
var i = 0;
foreach (var (state, count) in rawMeasurements)
{
// some boxing here, but it's fine
var tag = new KeyValuePair<string, object?>("tcp.state", state);
realMeasurements[i] = new Measurement<int>(count, tag);
i++;
}
return realMeasurements;
}, units, description);
public static ObservableGauge<int> TrackActiveTcpListeners(string metricName, string description,
string units = TcpListenersUnit, Predicate<IPEndPoint>? keepData = null)
=> Meter.CreateObservableGauge<int>(metricName,
() =>
{
keepData ??= DefaultListeningEndpointKeepFn;
IPGlobalProperties properties = IPGlobalProperties.GetIPGlobalProperties();
var endPoints = properties.GetActiveTcpListeners().Where(c => keepData(c));
return endPoints.Select(c =>
{
var tags = new[]
{
new KeyValuePair<string, object?>("listener_addr", c.Address),
new KeyValuePair<string, object?>("listener_port", c.Port),
new KeyValuePair<string, object?>("ip_family", c.AddressFamily)
};
return new Measurement<int>(1, tags);
});
}, units, description);
}
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