SimpleMetrics 1.0.1

SimpleMetrics

Goals

• Start working with metrics easily
• Ensure best practices are used

What is it

This is a wrapper around App.Metrics that is more suitable for our organisation.

• uses Autofac for dependcy injection
• can act as an extra layer in naming/managing metrics in your codebase
• formats as prometheus

Configuration

Adding SimpleMetrics to your project

Install-Package SimpleMetrics

In your autofac dependency registration

builder.RegisterModule<MetricsModule>();

Incrementing a counter

Inject:

private readonly IIncrementMetricsCounters _metricsCounterIncrementer;

Create a model:

public class UserClickedSomethingMetric : IMetricsModel
{
    public UserClickedSomethingMetric()
    {
        this.Tags = new Dictionary<string, string>();
    }

    public string Namespace => "MyApplication";
    public string ThingBeingMeasured => "findandreplace_clicked_find";
    public string Unit => string.Empty;
    public string Suffix => "total";
    public Dictionary<string, string> Tags { get; }
}

Increment the counter

_metricsCounterIncrementer.Increment(new UserClickedFindMetric());

Adding a metric endpoint for prometheus to scrape

Add a controller:

[Route("metrics")]
public class MetricsController : Controller
{
    private readonly IProvideMetricSnapshots _metricsSnapshotProvider;

    public MetricsController(IProvideMetricSnapshots metricsSnapshotProvider)
    {
        _metricsSnapshotProvider = metricsSnapshotProvider;
    }

    [HttpGet]
    public ActionResult Metrics()
    {
        var snapshot = _metricsSnapshotProvider.Provide();

        return new ContentResult() {Content = snapshot, ContentEncoding = Encoding.UTF8, ContentType = "text/html"};
    }
}

If you use an ApiController

[Route("metrics")]
[HttpGet]
public HttpResponseMessage Get()
{
    var snapshot = _metricSnapshotProvider.Provide();

    return new HttpResponseMessage()
    {
        Content = new StringContent(
            snapshot,
            Encoding.UTF8,
            "text/html"
        )
    };
}