feat: add Prometheus metrics for API

PluralKit.API/PluralKit.API.csproj

@@ -28,7 +28,9 @@
     </PropertyGroup>
 
     <ItemGroup>
-        <PackageReference Include="App.Metrics.AspNetCore.Mvc" Version="4.3.0" />
+        <PackageReference Include="App.Metrics.AspNetCore.All" Version="4.3.0" />
+        <PackageReference Include="App.Metrics.Prometheus" Version="4.3.0" />
+        <PackageReference Include="App.Metrics.Reporting.Console" Version="4.3.0" />
         <PackageReference Include="Google.Protobuf" Version="3.13.0" />
         <PackageReference Include="Grpc.Tools" Version="2.37.0" PrivateAssets="All" />
         <PackageReference Include="Microsoft.AspNetCore.Mvc.NewtonsoftJson" Version="3.1.0" />

PluralKit.API/Program.cs

@@ -1,4 +1,6 @@
+using App.Metrics;
 using App.Metrics.AspNetCore;
+using App.Metrics.Formatters.Prometheus;
 
 using Autofac.Extensions.DependencyInjection;
 
@@ -10,8 +12,15 @@ namespace PluralKit.API;
 
 public class Program
 {
+    public static IMetricsRoot _metrics { get; set; }
+
     public static async Task Main(string[] args)
     {
+        _metrics = AppMetrics.CreateDefaultBuilder()
+            .OutputMetrics.AsPrometheusPlainText()
+            .OutputMetrics.AsPrometheusProtobuf()
+            .Build();
+
         InitUtils.InitStatic();
         await BuildInfoService.LoadVersion();
         var host = CreateHostBuilder(args).Build();
@@ -22,7 +31,18 @@ public class Program
 
     public static IHostBuilder CreateHostBuilder(string[] args) =>
         Host.CreateDefaultBuilder(args)
-            .UseMetrics()
+            .ConfigureMetrics(_metrics)
+            .UseMetricsWebTracking()
+            .UseMetricsEndpoints()
+            .UseMetrics(
+            options =>
+            {
+                options.EndpointOptions = endpointsOptions =>
+                {
+                    endpointsOptions.MetricsTextEndpointOutputFormatter = _metrics.OutputMetricsFormatters.OfType<MetricsPrometheusTextOutputFormatter>().First();
+                    endpointsOptions.MetricsEndpointOutputFormatter = _metrics.OutputMetricsFormatters.OfType<MetricsPrometheusProtobufOutputFormatter>().First();
+                };
+            })
             .UseServiceProviderFactory(new AutofacServiceProviderFactory())
             .UseSerilog()
             .ConfigureWebHostDefaults(whb => whb

PluralKit.API/Startup.cs

@@ -2,6 +2,8 @@ using System.Reflection;
 
 using Autofac;
 
+using App.Metrics.AspNetCore;
+
 using Microsoft.AspNetCore.Authentication;
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Diagnostics;
@@ -86,6 +88,10 @@ public class Startup
             c.IncludeXmlComments(xmlPath);
         });
         services.AddSwaggerGenNewtonsoftSupport();
+
+        // metrics
+        services.AddMetricsTrackingMiddleware();
+        services.AddAppMetricsCollectors();
     }
 
     public void ConfigureContainer(ContainerBuilder builder)
@@ -95,7 +101,7 @@ public class Startup
         builder.RegisterModule(new ConfigModule<ApiConfig>("API"));
         builder.RegisterModule(new LoggingModule("api",
             cfg: new LoggerConfiguration().Filter.ByExcluding(exc => exc.Exception is PKError || exc.Exception.IsUserError())));
-        builder.RegisterModule(new MetricsModule("API"));
+        // builder.RegisterModule(new MetricsModule("API"));
         builder.RegisterModule<DataStoreModule>();
         builder.RegisterModule<APIModule>();
     }
@@ -164,5 +170,8 @@ public class Startup
         app.UseAuthentication();
         app.UseAuthorization();
         app.UseEndpoints(endpoints => endpoints.MapControllers());
+
+        // metrics
+        app.UseMetricsAllMiddleware();
     }
 }

PluralKit.API/packages.lock.json

@@ -2,15 +2,43 @@
   "version": 1,
   "dependencies": {
     "net6.0": {
-      "App.Metrics.AspNetCore.Mvc": {
+      "App.Metrics.AspNetCore.All": {
         "type": "Direct",
         "requested": "[4.3.0, )",
         "resolved": "4.3.0",
-        "contentHash": "CvsIUrUFS6sWimxKRl9RChDtOAGY36yW3HSTNXSaUrbFpmF76qL2HKiXu+4vSpO0Xau+fk7TdJvGRiG5RWGj0A==",
+        "contentHash": "ZCc2GSoDdmwxvacu9Rc/2TFtMW33KPWXfRbLF9yemEKalO5CQvDtZbCs9E1dDCEofeeI2Eho0ky86Brm3lXm4g==",
         "dependencies": {
           "App.Metrics.AspNetCore": "4.3.0",
-          "App.Metrics.AspNetCore.Mvc.Core": "4.3.0",
+          "App.Metrics.AspNetCore.Endpoints": "4.3.0",
-          "App.Metrics.AspNetCore.Routing": "4.3.0"
+          "App.Metrics.AspNetCore.Hosting": "4.3.0",
+          "App.Metrics.AspNetCore.Mvc": "4.3.0",
+          "App.Metrics.AspNetCore.Routing": "4.3.0",
+          "App.Metrics.AspNetCore.Tracking": "4.3.0",
+          "App.Metrics.Extensions.Collectors": "4.3.0",
+          "App.Metrics.Extensions.Configuration": "4.3.0",
+          "App.Metrics.Extensions.DependencyInjection": "4.3.0",
+          "App.Metrics.Extensions.HealthChecks": "4.3.0",
+          "App.Metrics.Extensions.Hosting": "4.3.0",
+          "App.Metrics.Formatters.Json": "4.3.0"
+        }
+      },
+      "App.Metrics.Prometheus": {
+        "type": "Direct",
+        "requested": "[4.3.0, )",
+        "resolved": "4.3.0",
+        "contentHash": "QhEL8zqnmOuaaSEUfQmWrqBEYt3MI3hb5Qhmlln72wUjyWzFkadA6QgzrQmG7K0lYqsj269BYcg42cL9T7wg6g==",
+        "dependencies": {
+          "App.Metrics.Formatters.Prometheus": "4.3.0"
+        }
+      },
+      "App.Metrics.Reporting.Console": {
+        "type": "Direct",
+        "requested": "[4.3.0, )",
+        "resolved": "4.3.0",
+        "contentHash": "LhQQd+CTwQ6YXpg53Bnt9seGh/zKDMWF/hWPIYVUUv5163PpexIFgvH85U7J1+Yjxrka95OEv5O/uUGxPQcyHg==",
+        "dependencies": {
+          "App.Metrics.Core": "4.3.0",
+          "App.Metrics.Formatters.Ascii": "4.3.0"
         }
       },
       "Google.Protobuf": {
@@ -194,6 +222,16 @@
           "App.Metrics.AspNetCore.Core": "4.3.0"
         }
       },
+      "App.Metrics.AspNetCore.Mvc": {
+        "type": "Transitive",
+        "resolved": "4.3.0",
+        "contentHash": "CvsIUrUFS6sWimxKRl9RChDtOAGY36yW3HSTNXSaUrbFpmF76qL2HKiXu+4vSpO0Xau+fk7TdJvGRiG5RWGj0A==",
+        "dependencies": {
+          "App.Metrics.AspNetCore": "4.3.0",
+          "App.Metrics.AspNetCore.Mvc.Core": "4.3.0",
+          "App.Metrics.AspNetCore.Routing": "4.3.0"
+        }
+      },
       "App.Metrics.AspNetCore.Mvc.Core": {
         "type": "Transitive",
         "resolved": "4.3.0",
@@ -235,6 +273,16 @@
           "Microsoft.CSharp": "4.4.0"
         }
       },
+      "App.Metrics.Extensions.Collectors": {
+        "type": "Transitive",
+        "resolved": "4.3.0",
+        "contentHash": "vpWzbLJ2uUnaR6s/bp4F1mZNf5vxMvFA0re+bUbQ8gkop7AEJZ1g3uFdQs7mSeL56josQBGnwbMediVst5zywA==",
+        "dependencies": {
+          "App.Metrics": "4.3.0",
+          "Microsoft.Extensions.DependencyInjection.Abstractions": "3.1.0",
+          "Microsoft.Extensions.Hosting.Abstractions": "3.1.0"
+        }
+      },
       "App.Metrics.Extensions.Configuration": {
         "type": "Transitive",
         "resolved": "4.3.0",
@@ -253,6 +301,16 @@
           "Microsoft.Extensions.DependencyInjection.Abstractions": "3.1.0"
         }
       },
+      "App.Metrics.Extensions.HealthChecks": {
+        "type": "Transitive",
+        "resolved": "4.3.0",
+        "contentHash": "uLpWgl9flmsDTYuYvIOjjo3tEsn3H951OS3ItS2tqi/wgGGpwAXwRW+HB/meB8W6PBRmISPQCUwNJudRerH5zA==",
+        "dependencies": {
+          "App.Metrics.Core": "4.3.0",
+          "Microsoft.Extensions.DependencyInjection.Abstractions": "3.1.0",
+          "Microsoft.Extensions.Diagnostics.HealthChecks.Abstractions": "3.1.5"
+        }
+      },
       "App.Metrics.Extensions.Hosting": {
         "type": "Transitive",
         "resolved": "4.3.0",
@@ -286,6 +344,15 @@
           "System.Text.Json": "4.7.2"
         }
       },
+      "App.Metrics.Formatters.Prometheus": {
+        "type": "Transitive",
+        "resolved": "4.3.0",
+        "contentHash": "cVJZX5jiMxt+YytjpbMw52reN47LGL3XsCljzNH9Pb+Op9iSTazc4pa+/fX+FdpbhH/Zt+5hjdYiqOLFol0wGg==",
+        "dependencies": {
+          "App.Metrics.Core": "4.3.0",
+          "protobuf-net": "2.4.0"
+        }
+      },
       "App.Metrics.Reporting.InfluxDB": {
         "type": "Transitive",
         "resolved": "4.1.0",
@@ -491,6 +558,11 @@
           "System.Linq": "4.1.0"
         }
       },
+      "Microsoft.Extensions.Diagnostics.HealthChecks.Abstractions": {
+        "type": "Transitive",
+        "resolved": "3.1.5",
+        "contentHash": "6oo7BLy4cdYGegZJ2d3YXUFT9Pb1Pp2kq8QuTSG7oZOQ6nF0QgHMwJPX/zQqTeWVDbA+UsFaZ4QNyUGHdG5VEg=="
+      },
       "Microsoft.Extensions.FileProviders.Abstractions": {
         "type": "Transitive",
         "resolved": "3.1.10",
@@ -515,13 +587,13 @@
       },
       "Microsoft.Extensions.Hosting.Abstractions": {
         "type": "Transitive",
-        "resolved": "2.1.0",
+        "resolved": "3.1.0",
-        "contentHash": "BpMaoBxdXr5VD0yk7rYN6R8lAU9X9JbvsPveNdKT+llIn3J5s4sxpWqaSG/NnzTzTLU5eJE5nrecTl7clg/7dQ==",
+        "contentHash": "LiOP1ceFaPBxaE28SOjtORzOVCJk33TT5VQ/Cg5EoatZh1dxpPAgAV/0ruzWKQE7WAHU3F1H9Z6rFgsQwIb9uQ==",
         "dependencies": {
-          "Microsoft.Extensions.Configuration.Abstractions": "2.1.0",
+          "Microsoft.Extensions.Configuration.Abstractions": "3.1.0",
-          "Microsoft.Extensions.DependencyInjection.Abstractions": "2.1.0",
+          "Microsoft.Extensions.DependencyInjection.Abstractions": "3.1.0",
-          "Microsoft.Extensions.FileProviders.Abstractions": "2.1.0",
+          "Microsoft.Extensions.FileProviders.Abstractions": "3.1.0",
-          "Microsoft.Extensions.Logging.Abstractions": "2.1.0"
+          "Microsoft.Extensions.Logging.Abstractions": "3.1.0"
         }
       },
       "Microsoft.Extensions.Logging": {
@@ -652,6 +724,14 @@
           "System.IO.Pipelines": "5.0.0"
         }
       },
+      "protobuf-net": {
+        "type": "Transitive",
+        "resolved": "2.4.0",
+        "contentHash": "j37MD1p1s9NdX8P5+IaY2J9p2382xiL1VP3mxYu0g+G/kf2YM2grFa1jJPO+0WDJNl1XhNPO0Q5yBEcbX77hBQ==",
+        "dependencies": {
+          "System.ServiceModel.Primitives": "4.5.3"
+        }
+      },
       "runtime.native.System": {
         "type": "Transitive",
         "resolved": "4.3.0",
@@ -1076,6 +1156,16 @@
           "System.Threading": "4.0.11"
         }
       },
+      "System.Private.ServiceModel": {
+        "type": "Transitive",
+        "resolved": "4.5.3",
+        "contentHash": "ancrQgJagx+yC4SZbuE+eShiEAUIF0E1d21TRSoy1C/rTwafAVcBr/fKibkq5TQzyy9uNil2tx2/iaUxsy0S9g==",
+        "dependencies": {
+          "Microsoft.NETCore.Platforms": "2.1.0",
+          "System.Reflection.DispatchProxy": "4.5.0",
+          "System.Security.Principal.Windows": "4.5.0"
+        }
+      },
       "System.Reflection": {
         "type": "Transitive",
         "resolved": "4.3.0",
@@ -1088,6 +1178,11 @@
           "System.Runtime": "4.3.0"
         }
       },
+      "System.Reflection.DispatchProxy": {
+        "type": "Transitive",
+        "resolved": "4.5.0",
+        "contentHash": "+UW1hq11TNSeb+16rIk8hRQ02o339NFyzMc4ma/FqmxBzM30l1c2IherBB4ld1MNcenS48fz8tbt50OW4rVULA=="
+      },
       "System.Reflection.Emit": {
         "type": "Transitive",
         "resolved": "4.7.0",
@@ -1239,6 +1334,14 @@
         "resolved": "5.0.0",
         "contentHash": "t0MGLukB5WAVU9bO3MGzvlGnyJPgUlcwerXn1kzBRjwLKixT96XV0Uza41W49gVd8zEMFu9vQEFlv0IOrytICA=="
       },
+      "System.ServiceModel.Primitives": {
+        "type": "Transitive",
+        "resolved": "4.5.3",
+        "contentHash": "Wc9Hgg4Cmqi416zvEgq2sW1YYCGuhwWzspDclJWlFZqY6EGhFUPZU+kVpl5z9kAgrSOQP7/Uiik+PtSQtmq+5A==",
+        "dependencies": {
+          "System.Private.ServiceModel": "4.5.3"
+        }
+      },
       "System.Text.Encoding": {
         "type": "Transitive",
         "resolved": "4.3.0",