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Error Monitoring / Logging / Tracing in .NET via the OpenTelemetry Protocol (OTLP).
.NET supports OpenTelemetry instrumentation out of the box.

Below, we explain how to define a HighlightConfig class which will setup opentelemetry export to highlight.

Install dependencies.

Run the following in your .NET project to install dependencies.

dotnet add package OpenTelemetry.Exporter.Console dotnet add package OpenTelemetry.Exporter.OpenTelemetryProtocol dotnet add package OpenTelemetry.Extensions.Hosting dotnet add package OpenTelemetry.Extensions.Hosting dotnet add package OpenTelemetry.Instrumentation.AspNetCore dotnet add package Serilog.Enrichers.Environment dotnet add package Serilog.Sinks.Async dotnet add package Serilog.Sinks.OpenTelemetry
Define the Highlight configuration class.

Copy the following code into a HighlightConfig.cs file in your project.

using System.Diagnostics; using OpenTelemetry; using OpenTelemetry.Exporter; using OpenTelemetry.Logs; using OpenTelemetry.Metrics; using OpenTelemetry.Resources; using OpenTelemetry.Trace; using Serilog.Context; using Serilog.Core; using Serilog.Events; using Serilog.Sinks.OpenTelemetry; namespace dotnet; public class HighlightTraceProcessor : BaseProcessor<Activity> { public override void OnStart(Activity data) { var ctx = HighlightConfig.GetHighlightContext(); foreach (var entry in ctx) { data.SetTag(entry.Key, entry.Value); } base.OnStart(data); } } public class HighlightLogProcessor : BaseProcessor<LogRecord> { public override void OnStart(LogRecord data) { var ctx = HighlightConfig.GetHighlightContext(); var attributes = ctx.Select(entry => new KeyValuePair<string, object?>(entry.Key, entry.Value)).ToList(); if (data.Attributes != null) { attributes = attributes.Concat(data.Attributes).ToList(); } data.Attributes = attributes; base.OnStart(data); } } public class HighlightLogEnricher : ILogEventEnricher { public void Enrich(LogEvent logEvent, ILogEventPropertyFactory pf) { var ctx = HighlightConfig.GetHighlightContext(); foreach (var entry in ctx) { logEvent.AddOrUpdateProperty(pf.CreateProperty(entry.Key, entry.Value)); } } } public class HighlightConfig { // Replace with the highlight endpoint. For cloud, use public static readonly String OtlpEndpoint = "http://localhost:4318"; // Replace with your project ID and service name. public static readonly String ProjectId = "<YOUR_PROJECT_ID>"; public static readonly String ServiceName = "highlight-dot-net-example"; public static readonly String TracesEndpoint = OtlpEndpoint + "/v1/traces"; public static readonly String LogsEndpoint = OtlpEndpoint + "/v1/logs"; public static readonly String MetricsEndpoint = OtlpEndpoint + "/v1/metrics"; public static readonly OtlpProtocol Protocol = OtlpProtocol.HttpProtobuf; public static readonly OtlpExportProtocol ExportProtocol = OtlpExportProtocol.HttpProtobuf; public static readonly String HighlightHeader = "x-highlight-request"; public static readonly Dictionary<string, object> ResourceAttributes = new() { ["highlight.project_id"] = ProjectId, [""] = ServiceName, }; public static Dictionary<string, string> GetHighlightContext() { var ctx = new Dictionary<string, string> { { "highlight.project_id", ProjectId }, }; var headerValue = Baggage.GetBaggage(HighlightHeader); if (headerValue == null) return ctx; var parts = headerValue.Split("/"); if (parts.Length < 2) return ctx; ctx["highlight.session_id"] = parts[0]; ctx["highlight.trace_id"] = parts[1]; return ctx; } public static void EnrichWithHttpRequest(Activity activity, HttpRequest httpRequest) { var headerValues = httpRequest.Headers[HighlightHeader]; if (headerValues.Count < 1) return; var headerValue = headerValues[0]; if (headerValue == null) return; var parts = headerValue.Split("/"); if (parts?.Length < 2) return; activity.SetTag("highlight.session_id", parts?[0]); activity.SetTag("highlight.trace_id", parts?[1]); Baggage.SetBaggage(new KeyValuePair<string, string>[] { new(HighlightHeader, headerValue) }); } public static void Configure(WebApplicationBuilder builder) { builder.Logging.AddOpenTelemetry(options => { options .SetResourceBuilder(ResourceBuilder.CreateDefault().AddAttributes(ResourceAttributes)) .AddProcessor(new HighlightLogProcessor()) .AddOtlpExporter(exporterOptions => { exporterOptions.Endpoint = new Uri(LogsEndpoint); exporterOptions.Protocol = ExportProtocol; }); }); builder.Services.AddOpenTelemetry() .ConfigureResource(resource => resource.AddAttributes(ResourceAttributes)) .WithTracing(tracing => tracing .AddSource(ServiceName) .AddProcessor(new HighlightTraceProcessor()) .AddAspNetCoreInstrumentation(options => { options.RecordException = true; options.EnrichWithHttpRequest = EnrichWithHttpRequest; }) .AddOtlpExporter(options => { options.Endpoint = new Uri(TracesEndpoint); options.Protocol = ExportProtocol; })) .WithMetrics(metrics => metrics .AddMeter(ServiceName) .AddAspNetCoreInstrumentation() .AddOtlpExporter(options => { options.Endpoint = new Uri(MetricsEndpoint); options.Protocol = ExportProtocol; })); } }
Bootstrap Highlight with your ASP application object.

Copy the following code into a HighlightConfig.cs file in your project.

using System.Diagnostics; using dotnet; using OpenTelemetry.Trace; using Serilog; var builder = WebApplication.CreateBuilder(args); // configure your web application // create a Serilog logger with Highlight export Log.Logger = new LoggerConfiguration() .Enrich.WithMachineName() .Enrich.With<HighlightLogEnricher>() .Enrich.FromLogContext() .WriteTo.Async(async => async.OpenTelemetry(options => { options.Endpoint = HighlightConfig.LogsEndpoint; options.Protocol = HighlightConfig.Protocol; options.ResourceAttributes = HighlightConfig.ResourceAttributes; }) ) .CreateLogger(); // Initialize trace, error, and log export HighlightConfig.Configure(builder); var app = builder.Build();
Verify your errors are being recorded.

Verify that the backend error handling works by triggering the code that reports the error to highlight and visiting the highlight errors portal.

Verify your backend logs are being recorded.

Visit the highlight logs portal and check that backend logs are coming in.

Verify your backend traces are being recorded.

Visit the highlight traces portal and check that backend traces are coming in.