Use DI container to resolve CollectorREgistry

Author: sanych-sun

src/Prometheus.Client.MetricServer/MetricServer.cs

@@ -1,7 +1,5 @@
 using System;
-#if !NETSTANDARD13
 using System.Net;
-#endif
 using System.Reflection;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
@@ -46,7 +44,7 @@ public MetricServer(ICollectorRegistry registry, MetricServerOptions options)
             if (string.IsNullOrEmpty(options.MapPath) || !options.MapPath.StartsWith("/"))
                 throw new ArgumentException($"mapPath '{options.MapPath}' should start with '/'");
 
-            _registry = registry ?? Metrics.DefaultCollectorRegistry;
+            _registry = registry;
             _options = options;
         }
 
@@ -68,15 +66,8 @@ public void Start()
                 .UseConfiguration(config)
                 .UseKestrel(options =>
                 {
-#if NETSTANDARD13
-                    if (_options.Certificate != null)
-                        options.UseHttps(_options.Certificate);
-#endif
-
-#if !NETSTANDARD13
                     if (_options.Certificate != null)
                         options.Listen(IPAddress.Any, _options.Port, listenOptions => { listenOptions.UseHttps(_options.Certificate); });
-#endif
                 })
                 .UseUrls($"http{(_options.Certificate != null ? "s" : "")}://{_options.Host}:{_options.Port}")
                 .ConfigureServices(services => { services.AddSingleton<IStartup>(new Startup(_registry, _options.MapPath)); })
@@ -100,7 +91,7 @@ internal class Startup : IStartup
         {
             private const string _contentType = "text/plain; version=0.0.4";
 
-            private readonly ICollectorRegistry _registry;
+            private ICollectorRegistry _registry;
             private readonly string _mapPath;
 
             public Startup(ICollectorRegistry registry, string mapPath)
@@ -121,6 +112,9 @@ public IServiceProvider ConfigureServices(IServiceCollection services)
 
             public void Configure(IApplicationBuilder app)
             {
+                _registry ??= (ICollectorRegistry)app.ApplicationServices.GetService(typeof(ICollectorRegistry))
+                           ?? Metrics.DefaultCollectorRegistry;
+
                 app.Map(_mapPath, coreapp =>
                 {
                     coreapp.Run(async context =>

src/Prometheus.Client.MetricServer/Prometheus.Client.MetricServer.csproj

@@ -1,11 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <Description>MetricServer for the Prometheus.Client</Description>
-    <Copyright>2019 © Sergey Kuznetsov</Copyright>
+    <Copyright>2020 © Serge K, Oleksandr Poliakov</Copyright>
     <AssemblyTitle>Prometheus.Client.MetricServer</AssemblyTitle>
-    <VersionPrefix>3.1.0</VersionPrefix>
-    <Authors>Sergey Kuznetsov, Oleksandr Poliakov</Authors>
-    <TargetFrameworks>netstandard1.3;netstandard2.0;netcoreapp2.2;netstandard2.1</TargetFrameworks>
+    <VersionPrefix>4.1.0</VersionPrefix>
+    <Authors>Serge K, Oleksandr Poliakov</Authors>
+    <TargetFrameworks>netstandard2.0;netcoreapp2.2;netstandard2.1</TargetFrameworks>
+    <LangVersion>latest</LangVersion>
     <AssemblyName>Prometheus.Client.MetricServer</AssemblyName>
     <PackageId>Prometheus.Client.MetricServer</PackageId>
     <PackageTags>prometheus;metrics</PackageTags>
@@ -23,14 +24,7 @@
     <None Include="../../icon.png" Pack="true" Visible="false" PackagePath="" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Prometheus.Client" Version="[3.1.0,4.0.0)" />
-  </ItemGroup>
-  <PropertyGroup Condition=" '$(TargetFramework)' == 'netstandard1.3'">
-    <DefineConstants>$(DefineConstants);NETSTANDARD13</DefineConstants>
-  </PropertyGroup>
-  <ItemGroup Condition="'$(TargetFramework)' == 'netstandard1.3'">
-    <PackageReference Include="Microsoft.AspNetCore.Server.Kestrel" Version="1.1.3" />
-    <PackageReference Include="Microsoft.AspNetCore.Server.Kestrel.Https" Version="1.1.3" />
+    <PackageReference Include="Prometheus.Client" Version="4.1.0" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0' OR '$(TargetFramework)' == 'netcoreapp2.2' OR '$(TargetFramework)' == 'netstandard2.1'">
     <PackageReference Include="Microsoft.AspNetCore.Server.Kestrel" Version="2.2.0" />