[Prometheus] Split up projects based on hosting mechanism.

OpenTelemetry.sln

@@ -237,6 +237,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenTelemetry.Extensions.Pr
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "correlation", "docs\logs\correlation\correlation.csproj", "{9A07D215-90AC-4BAF-BCDB-73D74FD3A5C5}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OpenTelemetry.Exporter.Prometheus.HttpListener", "src\OpenTelemetry.Exporter.Prometheus.HttpListener\OpenTelemetry.Exporter.Prometheus.HttpListener.csproj", "{2006398C-AEF0-4CE2-990F-F76933E3542F}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "OpenTelemetry.Exporter.Prometheus.AspNetCore", "src\OpenTelemetry.Exporter.Prometheus.AspNetCore\OpenTelemetry.Exporter.Prometheus.AspNetCore.csproj", "{1AAF7405-7B82-4C84-9DA8-B0065F575DAE}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -487,6 +491,14 @@ Global
 		{9A07D215-90AC-4BAF-BCDB-73D74FD3A5C5}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{9A07D215-90AC-4BAF-BCDB-73D74FD3A5C5}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{9A07D215-90AC-4BAF-BCDB-73D74FD3A5C5}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2006398C-AEF0-4CE2-990F-F76933E3542F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2006398C-AEF0-4CE2-990F-F76933E3542F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2006398C-AEF0-4CE2-990F-F76933E3542F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2006398C-AEF0-4CE2-990F-F76933E3542F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{1AAF7405-7B82-4C84-9DA8-B0065F575DAE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1AAF7405-7B82-4C84-9DA8-B0065F575DAE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1AAF7405-7B82-4C84-9DA8-B0065F575DAE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1AAF7405-7B82-4C84-9DA8-B0065F575DAE}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

docs/metrics/getting-started-prometheus-grafana/Program.cs

@@ -18,6 +18,7 @@
 using System.Diagnostics.Metrics;
 using System.Threading;
 using OpenTelemetry;
+using OpenTelemetry.Exporter.Prometheus.HttpListener;
 using OpenTelemetry.Metrics;
 
 namespace GettingStartedPrometheusGrafana;
@@ -31,9 +32,12 @@ public static void Main()
     {
         using var meterProvider = Sdk.CreateMeterProviderBuilder()
             .AddMeter("MyCompany.MyProduct.MyLibrary")
-            .AddPrometheusExporter(options => { options.StartHttpListener = true; })
+            .AddPrometheusExporter()
             .Build();
 
+        using var listener = new PrometheusHttpListener(meterProvider);
+        listener.Start();
+
         Console.WriteLine("Press any key to exit");
         while (!Console.KeyAvailable)
         {

docs/metrics/getting-started-prometheus-grafana/README.md

@@ -46,7 +46,17 @@ And replace the below line:
 with
 
 ```csharp
-.AddPrometheusExporter(options => { options.StartHttpListener = true; })
+.AddPrometheusExporter()
+```
+
+After the meterProvider is successfully built, create a PrometheusHttpListener
+that takes in the meterProvider when constructed and passed in
+the listener options for configuration.
+call .Start() to start the listener.
+
+```csharp
+using var listener = new PrometheusHttpListener(meterProvider);
+listener.Start();
 ```
 
 With `AddPrometheusExporter()`, OpenTelemetry `PrometheusExporter` will export
@@ -60,7 +70,9 @@ graph LR
 subgraph SDK
   MeterProvider
   MetricReader[BaseExportingMetricReader]
-  PrometheusExporter["PrometheusExporter<br/>(http://localhost:9464/)"]
+  subgraph PrometheusHttpListener
+    PrometheusExporter["PrometheusExporter<br/>(http://localhost:9464/)"]
+  end
 end
 
 subgraph API

docs/metrics/getting-started-prometheus-grafana/getting-started-prometheus-grafana.csproj

@@ -1,5 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <ItemGroup>
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus\OpenTelemetry.Exporter.Prometheus.csproj" />
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus.HttpListener\OpenTelemetry.Exporter.Prometheus.HttpListener.csproj" />
   </ItemGroup>
 </Project>

examples/AspNet/Examples.AspNet.csproj

@@ -1,4 +1,4 @@
-<Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+<Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
   <PropertyGroup>
     <RestoreProjectStyle>PackageReference</RestoreProjectStyle>
@@ -118,6 +118,10 @@
       <Project>{52158a12-e7ef-45a1-859f-06f9b17410cb}</Project>
       <Name>OpenTelemetry.Exporter.Prometheus</Name>
     </ProjectReference>
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus.HttpListener\OpenTelemetry.Exporter.Prometheus.HttpListener.csproj">
+      <Project>{2006398c-aef0-4ce2-990f-f76933e3542f}</Project>
+      <Name>OpenTelemetry.Exporter.Prometheus.HttpListener</Name>
+    </ProjectReference>
   </ItemGroup>
   <PropertyGroup>
     <VisualStudioVersion Condition="'$(VisualStudioVersion)' == ''">10.0</VisualStudioVersion>

examples/AspNet/Global.asax.cs

@@ -22,6 +22,7 @@
 using System.Web.Routing;
 using OpenTelemetry;
 using OpenTelemetry.Exporter;
+using OpenTelemetry.Exporter.Prometheus.HttpListener;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Trace;
 
@@ -32,7 +33,8 @@ public class WebApiApplication : HttpApplication
 #pragma warning restore SA1649 // File name should match first type name
     {
         private IDisposable tracerProvider;
-        private IDisposable meterProvider;
+        private MeterProvider meterProvider;
+        private PrometheusHttpListener listener;
 
         protected void Application_Start()
         {
@@ -78,24 +80,28 @@ protected void Application_Start()
             switch (ConfigurationManager.AppSettings["UseMetricsExporter"].ToLowerInvariant())
             {
                 case "otlp":
-                    meterBuilder.AddOtlpExporter(otlpOptions =>
+                    this.meterProvider = meterBuilder.AddOtlpExporter(otlpOptions =>
                     {
                         otlpOptions.Endpoint = new Uri(ConfigurationManager.AppSettings["OtlpEndpoint"]);
-                    });
+                    })
+                    .Build();
                     break;
                 case "prometheus":
-                    meterBuilder.AddPrometheusExporter();
+                    this.meterProvider = meterBuilder.AddPrometheusExporter().Build();
+                    this.listener = new PrometheusHttpListener(
+                        this.meterProvider,
+                        o => o.HttpListenerPrefixes = new string[] { "http://localhost:9464/metrics" });
+                    this.listener.Start();
                     break;
                 default:
-                    meterBuilder.AddConsoleExporter((exporterOptions, metricReaderOptions) =>
+                    this.meterProvider = meterBuilder.AddConsoleExporter((exporterOptions, metricReaderOptions) =>
                     {
                         exporterOptions.Targets = ConsoleExporterOutputTargets.Debug;
-                    });
+                    })
+                    .Build();
                     break;
             }
 
-            this.meterProvider = meterBuilder.Build();
-
             GlobalConfiguration.Configure(WebApiConfig.Register);
 
             AreaRegistration.RegisterAllAreas();

examples/AspNetCore/Examples.AspNetCore.csproj

@@ -20,5 +20,6 @@
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Jaeger\OpenTelemetry.Exporter.Jaeger.csproj" />
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus\OpenTelemetry.Exporter.Prometheus.csproj" />
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Zipkin\OpenTelemetry.Exporter.Zipkin.csproj" />
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus.AspNetCore\OpenTelemetry.Exporter.Prometheus.AspNetCore.csproj" />
   </ItemGroup>
 </Project>

examples/Console/Examples.Console.csproj

@@ -36,5 +36,6 @@
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.InMemory\OpenTelemetry.Exporter.InMemory.csproj" />
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus\OpenTelemetry.Exporter.Prometheus.csproj" />
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.OpenTelemetryProtocol.Logs\OpenTelemetry.Exporter.OpenTelemetryProtocol.Logs.csproj" />
+    <ProjectReference Include="..\..\src\OpenTelemetry.Exporter.Prometheus.HttpListener\OpenTelemetry.Exporter.Prometheus.HttpListener.csproj" />
   </ItemGroup>
 </Project>

examples/Console/TestPrometheusExporter.cs

@@ -21,6 +21,7 @@
 using System.Threading;
 using System.Threading.Tasks;
 using OpenTelemetry;
+using OpenTelemetry.Exporter.Prometheus.HttpListener;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Trace;
 
@@ -53,12 +54,13 @@ internal static object Run(int port)
             .AddMeter(MyMeter2.Name)
             .AddPrometheusExporter(options =>
             {
-                options.StartHttpListener = true;
-                options.HttpListenerPrefixes = new string[] { $"http://localhost:{port}/" };
                 options.ScrapeResponseCacheDurationMilliseconds = 0;
             })
             .Build();
 
+        using var listener = new PrometheusHttpListener(meterProvider, o => o.HttpListenerPrefixes = new string[] { $"http://localhost:{port}/" });
+        listener.Start();
+
         var process = Process.GetCurrentProcess();
         MyMeter.CreateObservableCounter("thread.cpu_time", () => GetThreadCpuTime(process), "ms");
 

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/.publicApi/netcoreapp3.1/PublicAPI.Unshipped.txt

@@ -0,0 +1,9 @@
+Microsoft.AspNetCore.Builder.PrometheusExporterApplicationBuilderExtensions
+Microsoft.AspNetCore.Builder.PrometheusExporterEndpointRouteBuilderExtensions
+static Microsoft.AspNetCore.Builder.PrometheusExporterApplicationBuilderExtensions.UseOpenTelemetryPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Builder.IApplicationBuilder app) -> Microsoft.AspNetCore.Builder.IApplicationBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterApplicationBuilderExtensions.UseOpenTelemetryPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Builder.IApplicationBuilder app, OpenTelemetry.Metrics.MeterProvider meterProvider, System.Func<Microsoft.AspNetCore.Http.HttpContext, bool> predicate, string path, System.Action<Microsoft.AspNetCore.Builder.IApplicationBuilder> configureBranchedPipeline) -> Microsoft.AspNetCore.Builder.IApplicationBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterApplicationBuilderExtensions.UseOpenTelemetryPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Builder.IApplicationBuilder app, string path) -> Microsoft.AspNetCore.Builder.IApplicationBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterApplicationBuilderExtensions.UseOpenTelemetryPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Builder.IApplicationBuilder app, System.Func<Microsoft.AspNetCore.Http.HttpContext, bool> predicate) -> Microsoft.AspNetCore.Builder.IApplicationBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterEndpointRouteBuilderExtensions.MapPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Routing.IEndpointRouteBuilder endpoints) -> Microsoft.AspNetCore.Builder.IEndpointConventionBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterEndpointRouteBuilderExtensions.MapPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Routing.IEndpointRouteBuilder endpoints, string path = null, OpenTelemetry.Metrics.MeterProvider meterProvider = null, System.Action<Microsoft.AspNetCore.Builder.IApplicationBuilder> configureBranchedPipeline = null) -> Microsoft.AspNetCore.Builder.IEndpointConventionBuilder
+static Microsoft.AspNetCore.Builder.PrometheusExporterEndpointRouteBuilderExtensions.MapPrometheusScrapingEndpoint(this Microsoft.AspNetCore.Routing.IEndpointRouteBuilder endpoints, string path) -> Microsoft.AspNetCore.Builder.IEndpointConventionBuilder

src/OpenTelemetry.Exporter.Prometheus.AspNetCore/OpenTelemetry.Exporter.Prometheus.AspNetCore.csproj

@@ -0,0 +1,31 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <!-- OmniSharp/VS Code requires TargetFrameworks to be in descending order for IntelliSense and analysis. -->
+    <TargetFrameworks>netcoreapp3.1;net462</TargetFrameworks>
+    <Description>Prometheus exporter for OpenTelemetry .NET</Description>
+    <PackageTags>$(PackageTags);prometheus;metrics</PackageTags>
+    <MinVerTagPrefix>core-</MinVerTagPrefix>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <NoWarn>$(NoWarn),1591</NoWarn>
+  </PropertyGroup>
+
+  <!--Do not run ApiCompat as this package has never released a stable version.
+  Remove this property once we have released a stable version.-->
+  <PropertyGroup>
+    <RunApiCompat>false</RunApiCompat>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry\OpenTelemetry.csproj" />
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus\OpenTelemetry.Exporter.Prometheus.csproj" />
+  </ItemGroup>
+
+  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
+    <FrameworkReference Include="Microsoft.AspNetCore.App" />
+  </ItemGroup>
+
+</Project>
+

src/OpenTelemetry.Exporter.Prometheus/PrometheusExporterApplicationBuilderExtensions.cs → src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterApplicationBuilderExtensions.cs

@@ -20,7 +20,7 @@
 using Microsoft.AspNetCore.Http;
 using Microsoft.Extensions.DependencyInjection;
 using OpenTelemetry.Exporter;
-using OpenTelemetry.Exporter.Prometheus;
+using OpenTelemetry.Exporter.Prometheus.AspNetCore;
 using OpenTelemetry.Internal;
 using OpenTelemetry.Metrics;
 

src/OpenTelemetry.Exporter.Prometheus/PrometheusExporterEndpointRouteBuilderExtensions.cs → src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterEndpointRouteBuilderExtensions.cs

@@ -21,7 +21,7 @@
 using Microsoft.AspNetCore.Routing;
 using Microsoft.Extensions.DependencyInjection;
 using OpenTelemetry.Exporter;
-using OpenTelemetry.Exporter.Prometheus;
+using OpenTelemetry.Exporter.Prometheus.AspNetCore;
 using OpenTelemetry.Internal;
 using OpenTelemetry.Metrics;
 

src/OpenTelemetry.Exporter.Prometheus/Implementation/PrometheusExporterMiddleware.cs → src/OpenTelemetry.Exporter.Prometheus.AspNetCore/PrometheusExporterMiddleware.cs

@@ -22,7 +22,7 @@
 using OpenTelemetry.Internal;
 using OpenTelemetry.Metrics;
 
-namespace OpenTelemetry.Exporter.Prometheus
+namespace OpenTelemetry.Exporter.Prometheus.AspNetCore
 {
     /// <summary>
     /// ASP.NET Core middleware for exposing a Prometheus metrics scraping endpoint.

src/OpenTelemetry.Exporter.Prometheus.HttpListener/.publicApi/net462/PublicAPI.Unshipped.txt

@@ -0,0 +1,9 @@
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Dispose() -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.PrometheusHttpListener(OpenTelemetry.Metrics.MeterProvider meterProvider, System.Action<OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions> configure = null) -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Start(System.Threading.CancellationToken token = default(System.Threading.CancellationToken)) -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Stop() -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.HttpListenerPrefixes.get -> System.Collections.Generic.IReadOnlyCollection<string>
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.HttpListenerPrefixes.set -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.PrometheusHttpListenerOptions() -> void

src/OpenTelemetry.Exporter.Prometheus.HttpListener/.publicApi/netcoreapp3.1/PublicAPI.Unshipped.txt

@@ -0,0 +1,9 @@
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Dispose() -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.PrometheusHttpListener(OpenTelemetry.Metrics.MeterProvider meterProvider, System.Action<OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions> configure = null) -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Start(System.Threading.CancellationToken token = default(System.Threading.CancellationToken)) -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListener.Stop() -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.HttpListenerPrefixes.get -> System.Collections.Generic.IReadOnlyCollection<string>
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.HttpListenerPrefixes.set -> void
+OpenTelemetry.Exporter.Prometheus.HttpListener.PrometheusHttpListenerOptions.PrometheusHttpListenerOptions() -> void

src/OpenTelemetry.Exporter.Prometheus.HttpListener/OpenTelemetry.Exporter.Prometheus.HttpListener.csproj

@@ -0,0 +1,30 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <!-- OmniSharp/VS Code requires TargetFrameworks to be in descending order for IntelliSense and analysis. -->
+    <TargetFrameworks>netcoreapp3.1;net462</TargetFrameworks>
+    <Description>Prometheus exporter for OpenTelemetry .NET</Description>
+    <PackageTags>$(PackageTags);prometheus;metrics</PackageTags>
+    <MinVerTagPrefix>core-</MinVerTagPrefix>
+  </PropertyGroup>
+
+  <PropertyGroup>
+    <NoWarn>$(NoWarn),1591</NoWarn>
+  </PropertyGroup>
+
+  <!--Do not run ApiCompat as this package has never released a stable version.
+  Remove this property once we have released a stable version.-->
+  <PropertyGroup>
+    <RunApiCompat>false</RunApiCompat>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry\OpenTelemetry.csproj" />
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Prometheus\OpenTelemetry.Exporter.Prometheus.csproj" />
+  </ItemGroup>
+
+  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
+    <FrameworkReference Include="Microsoft.AspNetCore.App" />
+  </ItemGroup>
+
+</Project>