/// <summary>
/// Serialize to Prometheus Format.
/// </summary>
/// <param name="exporter">Prometheus Exporter.</param>
/// <param name="writer">StreamWriter to write to.</param>
public static void WriteMetricsCollection(this PrometheusExporter exporter, StreamWriter writer)
{
foreach (var metricItem in exporter.Batch)
{
foreach (var metric in metricItem.Metrics)
{
var builder = new PrometheusMetricBuilder()
.WithName(metric.Name)
.WithDescription(metric.Description);
// TODO: Use switch case for higher perf.
if (metric.MetricType == MetricType.LongSum)
{
WriteSum(writer, builder, metric.Attributes, (metric as ISumMetricLong).LongSum);
}
else if (metric.MetricType == MetricType.DoubleSum)
{
WriteSum(writer, builder, metric.Attributes, (metric as ISumMetricDouble).DoubleSum);
}
else if (metric.MetricType == MetricType.DoubleGauge)
{
var gaugeMetric = metric as IGaugeMetric;
var doubleValue = (double)gaugeMetric.LastValue.Value;
WriteGauge(writer, builder, metric.Attributes, doubleValue);
}
else if (metric.MetricType == MetricType.LongGauge)
{
var gaugeMetric = metric as IGaugeMetric;
var longValue = (long)gaugeMetric.LastValue.Value;
// TODO: Prometheus only supports float/double
WriteGauge(writer, builder, metric.Attributes, longValue);
}
else if (metric.MetricType == MetricType.Histogram)
{
var histogramMetric = metric as IHistogramMetric;
WriteHistogram(writer, builder, metric.Attributes, metric.Name, histogramMetric.PopulationSum, histogramMetric.PopulationCount, histogramMetric.Buckets);
}
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="PrometheusExporterMetricsHttpServer"/> class.
/// </summary>
/// <param name="exporter">The <see cref="PrometheusExporter"/> instance.</param>
public PrometheusExporterMetricsHttpServer(PrometheusExporter exporter)
{
this.exporter = exporter ?? throw new ArgumentNullException(nameof(exporter));
this.httpListener.Prefixes.Add(exporter.Options.Url);
}
/// <summary>
/// Initializes a new instance of the <see cref="PrometheusExporterMiddleware"/> class.
/// </summary>
/// <param name="next">The next middleware in the pipeline.</param>
/// <param name="exporter">The <see cref="PrometheusExporter"/> instance.</param>
public PrometheusExporterMiddleware(RequestDelegate next, PrometheusExporter exporter)
{
this.exporter = exporter ?? throw new ArgumentNullException(nameof(exporter));
}