feat: add MetricPrefixName options

Author: phnx47

src/Prometheus.Client.AspNetCore/Prometheus.Client.AspNetCore.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Description>ASP.NET Core middleware for the Prometheus.Client</Description>
-    <VersionPrefix>4.4.0</VersionPrefix>
+    <VersionPrefix>4.5.0</VersionPrefix>
     <TargetFrameworks>netstandard2.0;netstandard2.1;netcoreapp3.1;net5.0</TargetFrameworks>
     <AssemblyName>Prometheus.Client.AspNetCore</AssemblyName>
     <PackageId>Prometheus.Client.AspNetCore</PackageId>
@@ -29,7 +29,7 @@
     </None>
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Prometheus.Client" Version="[4.4.0,5.0.0)" />
+    <PackageReference Include="Prometheus.Client" Version="4.5.1" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1' OR '$(TargetFramework)' == 'net5.0'">
     <FrameworkReference Include="Microsoft.AspNetCore.App" />

src/Prometheus.Client.AspNetCore/PrometheusExtensions.cs

@@ -23,9 +23,10 @@ public static IApplicationBuilder UsePrometheusServer(this IApplicationBuilder a
         /// </summary>
         public static IApplicationBuilder UsePrometheusServer(this IApplicationBuilder app, Action<PrometheusOptions> setupOptions)
         {
-            var options = new PrometheusOptions();
-            options.CollectorRegistryInstance
-                = (ICollectorRegistry)app.ApplicationServices.GetService(typeof(ICollectorRegistry)) ?? Metrics.DefaultCollectorRegistry;
+            var options = new PrometheusOptions
+            {
+                CollectorRegistryInstance = (ICollectorRegistry)app.ApplicationServices.GetService(typeof(ICollectorRegistry)) ?? Metrics.DefaultCollectorRegistry
+            };
 
             setupOptions?.Invoke(options);
 
@@ -39,7 +40,7 @@ public static IApplicationBuilder UsePrometheusServer(this IApplicationBuilder a
                 throw new ArgumentException($"MapPath '{options.MapPath}' should start with '/'");
 
             if (options.UseDefaultCollectors)
-                options.CollectorRegistryInstance.UseDefaultCollectors();
+                options.CollectorRegistryInstance.UseDefaultCollectors(options.MetricPrefixName);
 
             var contentType = "text/plain; version=0.0.4";
 

src/Prometheus.Client.AspNetCore/PrometheusOptions.cs

@@ -32,5 +32,10 @@ public class PrometheusOptions
         ///     Charset of text response.
         /// </summary>
         public Encoding ResponseEncoding { get; set; }
+
+        /// <summary>
+        ///     Metric prefix for Default collectors
+        /// </summary>
+        public string MetricPrefixName { get; set; } = "";
     }
 }