refactor: internal code

src/HttpRequestDurationsMiddlewareBuilderExtensions.cs → src/ApplicationBuilderExtensions.cs

@@ -4,7 +4,7 @@
 
 namespace Prometheus.Client.HttpRequestDurations;
 
-public static class PrometheusMiddlewareBuilderExtensions
+public static class ApplicationBuilderExtensions
 {
     /// <summary>
     ///     Metrics logging of request durations

src/HttpContextExtensions.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Linq;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.Mvc.Routing;
@@ -44,35 +45,27 @@ public static string GetRouteName(this HttpContext httpContext)
 
     private static string GetRouteDataKeyValue(this HttpContext httpContext, string routeDataKey)
     {
-        const string notFoundResult = "NotAvailable";
-
         if (httpContext == null)
             throw new ArgumentNullException(nameof(httpContext));
 
-        var routeData = httpContext.Features.Get<CapturedRouteDataFeature>()?.Values;
-
         // If we have captured route data, we always prefer it.
         // Otherwise, we extract new route data right now.
-        if (routeData == null)
-            routeData = httpContext.GetRouteData()?.Values;
+        var routeData = httpContext.Features.Get<RouteDataFeature>()?.Values ?? httpContext.GetRouteData().Values;
 
-        if (routeData?.Values.Count > 0)
+        if (routeData.Values.Count > 0)
         {
             var result = string.Empty;
 
-            foreach (var item in routeData)
+            foreach (var item in routeData.Where(item => item.Key == routeDataKey))
             {
-                if (item.Key == routeDataKey)
-                {
-                    result = item.Value?.ToString();
-                    break;
-                }
+                result = item.Value?.ToString();
+                break;
             }
 
             if (!string.IsNullOrEmpty(result))
                 return result;
         }
 
-        return notFoundResult;
+        return "NotAvailable";
     }
 }

src/HttpRequestDurationsMiddleware.cs

@@ -136,10 +136,7 @@ private void WriteMetrics(string statusCode, string method, string controller, s
             labelValues.Add(path);
 
         if (_options.CustomLabels != null)
-        {
-            foreach (var customLabel in _options.CustomLabels)
-                labelValues.Add(customLabel.Value());
-        }
+            labelValues.AddRange(_options.CustomLabels.Select(customLabel => customLabel.Value()));
 
         _histogram.WithLabels(labelValues.ToArray()).Observe(elapsedSeconds);
     }
@@ -149,16 +146,12 @@ private static void TryCaptureRouteData(HttpContext context)
         var routeData = context.GetRouteData();
 
         if (routeData.Values.Count == 0)
-        {
             return;
-        }
 
-        var capturedRouteData = new CapturedRouteDataFeature();
+        var capturedRouteData = new RouteDataFeature();
 
         foreach ((string key, object value) in routeData.Values)
-        {
             capturedRouteData.Values.Add(key, value);
-        }
 
         context.Features.Set(capturedRouteData);
     }

src/CapturedRouteDataFeature.cs → src/RouteDataFeature.cs

@@ -2,7 +2,7 @@
 
 namespace Prometheus.Client.HttpRequestDurations;
 
-internal class CapturedRouteDataFeature
+internal class RouteDataFeature
 {
     public RouteValueDictionary Values { get; } = new();
 }