Intellivega.Loki

Reusable .NET 10 Serilog integration for Loki, with local startup and delivery diagnostics.

Install and configure

Add https://baget.intellivega.com/v3/index.json to your NuGet sources, then install Intellivega.Loki. In an ASP.NET Core host:

using Intellivega.Loki;
using Serilog;

var builder = WebApplication.CreateBuilder(args);
builder.Host.UseIntellivegaLoki();
var app = builder.Build();
app.UseSerilogRequestLogging();
app.MapGet("/", () => "Hello");
app.Run();

The package registers console and Loki sinks. Remove those sinks from Serilog:WriteTo to avoid duplicate logging; additional sinks, enrichers, and minimum levels can still be configured through the normal Serilog section. Do not also call UseSerilog.

{
  "Loki": {
    "Uri": "http://coolify01.intellivega.com:3100",
    "ApplicationName": "my-application",
    "ServiceName": "web"
  },
  "Serilog": {
    "MinimumLevel": {
      "Default": "Information",
      "Override": { "Microsoft": "Warning", "System": "Warning" }
    }
  }
}

ASP.NET Core environment variables override JSON settings:

Environment is an additional label taken from the host environment, preserving case. Settings are read when the host is built; restart after changing them.

Diagnosing missing logs

Local stderr reports the endpoint and an exact Grafana label selector when the logger is configured, even if application log levels filter Information events. At host startup an Information marker is queued through the real sink. If that level is filtered, stderr says so. Only a real push response of HTTP 204 produces the first accepted-batch message. Failure responses, DNS/network/TLS failures and timeouts are reported locally; the first successful push after a failure reports recovery. Successful batches thereafter are quiet.

Diagnostics bypass Serilog to remain visible in container logs and avoid recursive failures. They do not include credentials, exception messages, or response bodies. An accepted batch confirms the ingestion endpoint acknowledged it; it does not verify Grafana's data source, query, tenant, or selected time range. No separate readiness probe is used. Set Loki:DiagnosticsEnabled to false for design-time hosts or tools that treat stderr as fatal. This does not disable console or Loki logging.

Delivery uses the upstream sink's asynchronous batching/retry behavior, a 10,000-event memory queue and a request timeout. It is not durable: queued logs can be lost on process failure or queue overflow. A Loki outage does not prevent host startup. Invalid required configuration does fail at startup. Host disposal flushes and disposes the logger.

Build, test, and publish

dotnet build -c Release
dotnet test -c Release
dotnet pack src/Intellivega.Loki -c Release -o artifacts
read -rsp "BaGet API key: " BAGET_API_KEY; echo
dotnet nuget push artifacts/Intellivega.Loki.1.0.1.nupkg \
  --source https://baget.intellivega.com/v3/index.json \
  --api-key "$BAGET_API_KEY"
unset BAGET_API_KEY

Publishing is manual, matching the existing Intellivega packages. GitHub Actions builds, tests, and uploads the NuGet package as a private workflow artifact; no publish key is stored in this repository. Increment Version in the project before publishing a new release.

The HTTP diagnostics extend the pinned Serilog Loki sink 8.3.1.