PR feat: track failed request

MetricFlow.sln

@@ -1,4 +1,4 @@
-Microsoft Visual Studio Solution File, Format Version 12.00
+Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.5.2.0
 MinimumVisualStudioVersion = 10.0.40219.1
@@ -14,6 +14,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MetricFlow.Tests", "tests\M
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DotnetKit.MetricFlow.Tracker", "src\DotnetKit.MetricFlow.Tracker\DotnetKit.MetricFlow.Tracker.csproj", "{60112D90-095C-44EA-90E9-846B4EDBF758}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "WebApiExample", "examples\WebApiExample\WebApiExample.csproj", "{62617707-AE70-492E-B36D-63D0108EC269}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -32,6 +34,10 @@ Global
 		{60112D90-095C-44EA-90E9-846B4EDBF758}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{60112D90-095C-44EA-90E9-846B4EDBF758}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{60112D90-095C-44EA-90E9-846B4EDBF758}.Release|Any CPU.Build.0 = Release|Any CPU
+		{62617707-AE70-492E-B36D-63D0108EC269}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{62617707-AE70-492E-B36D-63D0108EC269}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{62617707-AE70-492E-B36D-63D0108EC269}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{62617707-AE70-492E-B36D-63D0108EC269}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -40,6 +46,7 @@ Global
 		{78058871-2DC0-6810-ED9E-588E6E3A1265} = {B36A84DF-456D-A817-6EDD-3EC3E7F6E11F}
 		{3897CD1F-6CA5-41EC-9845-1979426CD7B8} = {01644C81-1609-407B-A964-A15BFA59E822}
 		{60112D90-095C-44EA-90E9-846B4EDBF758} = {827E0CD3-B72D-47B6-A68D-7590B98EB39B}
+		{62617707-AE70-492E-B36D-63D0108EC269} = {B36A84DF-456D-A817-6EDD-3EC3E7F6E11F}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {7CE4E738-181F-42CA-B63C-365DBD1BC7B9}

examples/WebApiExample/Program.cs

@@ -0,0 +1,86 @@
+using DotnetKit.MetricFlow.Tracker;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Add services to the container.
+// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen();
+builder.Services.AddSingleton(sp => new MetricTracker("WebApiExample"));
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+
+    //add a middleware to track API calls
+    app.Use(async (context, next) =>
+    {
+        //skip tracking metrics for the metrics endpoint
+        if (context.Request.Path == "/metrics")
+        {
+            await next();
+            return;
+        }
+        var tracker = context.RequestServices.GetRequiredService<MetricTracker>();
+        tracker.In(context.Request.Path);
+        //tracking requests with errors
+        try
+        {
+            await next();
+        }
+        catch (Exception e)
+        {
+            tracker.Out(context.Request.Path, new Dictionary<string, string>() { ["error_message"] = e.Message }, failed: true);
+            throw;
+        }
+        tracker.Out(context.Request.Path);
+    });
+}
+
+app.UseHttpsRedirection();
+
+var summaries = new[]
+{
+    "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
+};
+
+app.MapGet("/weatherforecast", () =>
+{
+    var forecast = Enumerable.Range(1, 5).Select(index =>
+        new WeatherForecast
+        (
+            DateOnly.FromDateTime(DateTime.Now.AddDays(index)),
+            Random.Shared.Next(-20, 55),
+            summaries[Random.Shared.Next(summaries.Length)]
+        ))
+        .ToArray();
+    return forecast;
+})
+.WithName("GetWeatherForecast")
+.WithOpenApi();
+
+app.MapGet("/throw_exception", () =>
+{
+    throw new Exception("This is an exception");
+})
+.WithName("Exception")
+.WithOpenApi();
+
+app.MapGet("/metrics", () =>
+{
+    var tracker = app.Services.GetRequiredService<MetricTracker>();
+    return tracker.ToString();
+
+})
+.WithName("Metrics")
+.WithOpenApi();
+
+app.Run();
+
+record WeatherForecast(DateOnly Date, int TemperatureC, string? Summary)
+{
+    public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
+}

examples/WebApiExample/Properties/launchSettings.json

@@ -0,0 +1,41 @@
+{
+  "$schema": "http://json.schemastore.org/launchsettings.json",
+  "iisSettings": {
+    "windowsAuthentication": false,
+    "anonymousAuthentication": true,
+    "iisExpress": {
+      "applicationUrl": "http://localhost:64475",
+      "sslPort": 44327
+    }
+  },
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "http://localhost:5045",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "applicationUrl": "https://localhost:7286;http://localhost:5045",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "IIS Express": {
+      "commandName": "IISExpress",
+      "launchBrowser": true,
+      "launchUrl": "swagger",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

examples/WebApiExample/README.md

@@ -0,0 +1,156 @@
+# Web API Example with MetricFlow
+
+This example demonstrates how to use the `MetricFlow` library to track and measure metrics in a .NET Web API application. The example includes a `Program` class that sets up the web application, configures middleware to track API calls, and exposes metrics via an endpoint.
+
+## Goal
+
+The goal of this example is to showcase how to integrate `MetricFlow` into a .NET Web API application to track various metrics such as request counts and durations for different API endpoints and indicate failed request count.
+
+This helps in monitoring the performance and usage of the API.
+
+## Overview of Implementation
+
+### Key Components
+
+- **MetricTracker:** Tracks metrics for different API endpoints.
+- **Middleware:** Automatically tracks metrics for incoming requests.
+- **Endpoints:** Demonstrates how to track metrics for specific API endpoints and expose metrics.
+
+### Implementation Details
+
+1. **Service Registration:**
+   - The `MetricTracker` service is registered as a global service in the dependency injection container.
+
+    ```csharp
+    builder.Services.AddSingleton<MetricTracker>(sp => new MetricTracker("WebApiExample"));
+    ```
+
+2. **Middleware Configuration:**
+   - Middleware is added to track metrics for incoming requests, excluding the `/metrics` endpoint.
+   - This oveview doesn't track failed requests, please look source code of this example for complete implementation.
+
+    ```csharp
+    app.Use(async (context, next) =>
+    {
+        if (context.Request.Path != "/metrics")
+        {
+            var tracker = context.RequestServices.GetRequiredService<MetricTracker>();
+            tracker.In(context.Request.Path);
+            await next();
+            tracker.Out(context.Request.Path);
+        }
+        else
+        {
+            await next();
+        }
+    });
+    ```
+
+3. **Endpoints:**
+   - The `/weatherforecast` endpoint simulates a weather forecast API and tracks metrics for the endpoint.
+   - The `/metrics` endpoint exposes the tracked metrics.
+
+    ```csharp
+    app.MapGet("/weatherforecast", (MetricTracker tracker) =>
+    {
+        tracker.In("GetWeatherForecast");
+        var forecast = Enumerable.Range(1, 5).Select(index =>
+            new WeatherForecast
+            (
+                DateOnly.FromDateTime(DateTime.Now.AddDays(index)),
+                Random.Shared.Next(-20, 55),
+                summaries[Random.Shared.Next(summaries.Length)]
+            ))
+            .ToArray();
+        tracker.Out("GetWeatherForecast");
+        return forecast;
+    })
+    .WithName("GetWeatherForecast")
+    .WithOpenApi();
+
+    app.MapGet("/metrics", (MetricTracker tracker) =>
+    {
+        return tracker.ToString();
+    })
+    .WithName("Metrics")
+    .WithOpenApi();
+    ```
+
+### Code Example
+
+```csharp
+using System.Diagnostics;
+using DotnetKit.MetricFlow.Tracker;
+using DotnetKit.MetricFlow.Tracker.Abstractions;
+
+var builder = WebApplication.CreateBuilder(args);
+
+// Add services to the container.
+builder.Services.AddEndpointsApiExplorer();
+builder.Services.AddSwaggerGen();
+builder.Services.AddSinglton<MetricTracker>(sp => new MetricTracker("WebApiExample"));
+
+var app = builder.Build();
+
+// Configure the HTTP request pipeline.
+if (app.Environment.IsDevelopment())
+{
+    app.UseSwagger();
+    app.UseSwaggerUI();
+}
+
+app.UseHttpsRedirection();
+
+app.Use(async (context, next) =>
+{
+    if (context.Request.Path != "/metrics")
+    {
+        var tracker = context.RequestServices.GetRequiredService<MetricTracker>();
+        tracker.In(context.Request.Path);
+        await next();
+        tracker.Out(context.Request.Path);
+    }
+    else
+    {
+        await next();
+    }
+});
+
+var summaries = new[]
+{
+    "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
+};
+
+app.MapGet("/weatherforecast", (MetricTracker tracker) =>
+{
+    tracker.In("GetWeatherForecast");
+    var forecast = Enumerable.Range(1, 5).Select(index =>
+        new WeatherForecast
+        (
+            DateOnly.FromDateTime(DateTime.Now.AddDays(index)),
+            Random.Shared.Next(-20, 55),
+            summaries[Random.Shared.Next(summaries.Length)]
+        ))
+        .ToArray();
+    tracker.Out("GetWeatherForecast");
+    return forecast;
+})
+.WithName("GetWeatherForecast")
+.WithOpenApi();
+
+app.MapGet("/metrics", (MetricTracker tracker) =>
+{
+    return tracker.ToString();
+})
+.WithName("Metrics")
+.WithOpenApi();
+
+app.Run();
+
+record WeatherForecast(DateOnly Date, int TemperatureC, string? Summary)
+{
+    public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);
+}
+```
+
+![alt text](image.png)

examples/WebApiExample/WebApiExample.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net8.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.4" />
+    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.4.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\DotnetKit.MetricFlow.Tracker\DotnetKit.MetricFlow.Tracker.csproj" />
+  </ItemGroup>
+
+</Project>

examples/WebApiExample/WebApiExample.http

@@ -0,0 +1,6 @@
+@WebApiExample_HostAddress = http://localhost:5045
+
+GET {{WebApiExample_HostAddress}}/weatherforecast/
+Accept: application/json
+
+###

examples/WebApiExample/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  }
+}

examples/WebApiExample/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

src/DotnetKit.MetricFlow.Tracker/Abstractions/CounterBase.cs

@@ -8,6 +8,7 @@ public abstract class CounterBase(string name, Dictionary<string, string>? metri
     private DateTime? _startedAt = null;
     private DateTime? _endedAt = null;
     private long _inCount = 0;
+    private long _failedCount = 0;
     private long _outCount = 0;
     private long _totalDuration = 0;
 
@@ -21,6 +22,7 @@ public abstract class CounterBase(string name, Dictionary<string, string>? metri
     public CounterValues Values => new CounterValues(
         Interlocked.Read(ref _inCount),
         Interlocked.Read(ref _outCount),
+        Interlocked.Read(ref _failedCount),
         TimeSpan.FromMilliseconds(Interlocked.Read(ref _totalDuration)),
         TimeSpan.FromMilliseconds(Interlocked.Read(ref _averageDuration)),
         TimeSpan.FromMilliseconds(Interlocked.Read(ref _minDuration)),
@@ -39,9 +41,14 @@ public long Inc()
         return Interlocked.Increment(ref _inCount);
     }
 
-    public long Dec()
+    public long Dec(bool? failed = false)
     {
         FinalizeState(Stop());
+
+        if (failed == true)
+        {
+            Interlocked.Increment(ref _failedCount);
+        }
         return Interlocked.Increment(ref _outCount);
     }