private static void RegisterCollectors(PrometheusOptions options)
{
if (options.UseDefaultCollectors)
{
var metricFactory = Metrics.DefaultFactory;
if (options.CollectorRegistryInstance != CollectorRegistry.Instance)
{
metricFactory = new MetricFactory(options.CollectorRegistryInstance);
}
options.Collectors.AddRange(DefaultCollectors.Get(metricFactory));
}
options.CollectorRegistryInstance.RegisterOnDemandCollectors(options.Collectors);
}
/// <summary>
/// Add PrometheusServer request execution pipeline.
/// </summary>
public static IAppBuilder UsePrometheusServer(this IAppBuilder app, Action <PrometheusOptions> setupOptions)
{
var options = new PrometheusOptions();
setupOptions?.Invoke(options);
if (app == null)
{
throw new ArgumentNullException(nameof(app));
}
if (options == null)
{
throw new ArgumentNullException(nameof(options));
}
if (!options.MapPath.StartsWith("/"))
{
throw new ArgumentException($"MapPath '{options.MapPath}' should start with '/'");
}
RegisterCollectors(options);
app.Map(options.MapPath, coreapp =>
{
coreapp.Run(async context =>
{
var req = context.Request;
var response = context.Response;
var acceptHeader = req.Headers.Get("Accept");
var acceptHeaders = acceptHeader?.Split(',');
var contentType = ScrapeHandler.GetContentType(acceptHeaders);
response.ContentType = contentType;
using (var outputStream = response.Body)
{
var collected = options.CollectorRegistryInstance.CollectAll();
ScrapeHandler.ProcessScrapeRequest(collected, contentType, outputStream);
}
await Task.FromResult(0).ConfigureAwait(false);
});
});
return(app);
}
