Porting of composable Health Checks

.gitignore

@@ -223,7 +223,7 @@ ClientBin/
 *.publishsettings
 orleans.codegen.cs
 
-# Including strong name files can present a security risk 
+# Including strong name files can present a security risk
 # (https://github.com/github/gitignore/pull/2483#issue-259490424)
 #*.snk
 
@@ -319,7 +319,7 @@ __pycache__/
 # OpenCover UI analysis results
 OpenCover/
 
-# Azure Stream Analytics local run output 
+# Azure Stream Analytics local run output
 ASALocalRun/
 
 # MSBuild Binary and Structured Log
@@ -328,5 +328,8 @@ ASALocalRun/
 # NVidia Nsight GPU debugger configuration file
 *.nvuser
 
-# MFractors (Xamarin productivity tool) working folder 
+# MFractors (Xamarin productivity tool) working folder
 .mfractor/
+
+# Disabling VSCode files
+.vscode/

Directory.Packages.props

@@ -7,9 +7,12 @@
   <ItemGroup Label="Package Versions. AutoUpdate">
     <PackageVersion Include="MSTest.TestAdapter" Version="3.1.1" />
     <PackageVersion Include="MSTest.TestFramework" Version="3.1.1" />
+    <PackageVersion Include="Microsoft.AspNetCore.Mvc" Version="2.1.1" />
+    <PackageVersion Include="Microsoft.AspNetCore.Mvc.Core" Version="2.1.16" />
     <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
     <PackageVersion Include="Microsoft.CodeAnalysis.Common" Version="4.6.0" />
     <PackageVersion Include="Microsoft.CodeAnalysis.Csharp" Version="4.6.0" />
+    <PackageVersion Include="Microsoft.Extensions.Caching.Memory" Version="7.0.0" />
     <PackageVersion Include="Microsoft.Extensions.Configuration.Binder" Version="7.0.4" />
     <PackageVersion Include="Microsoft.Extensions.DependencyInjection" Version="7.0.0" />
     <PackageVersion Include="Microsoft.Extensions.Diagnostics.HealthChecks" Version="7.0.10" />

Omex.sln

@@ -21,9 +21,9 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Solution Items", "Solution
 		.github\workflows\codeql-analysis.yml = .github\workflows\codeql-analysis.yml
 		Directory.Build.props = Directory.Build.props
 		Directory.Build.targets = Directory.Build.targets
+		Directory.Packages.props = Directory.Packages.props
 		global.json = global.json
 		NuGet.Config = NuGet.Config
-		Packages.props = Packages.props
 		README.md = README.md
 		ship.snk = ship.snk
 	EndProjectSection
@@ -70,6 +70,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Omex.Extensions.A
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Omex.Extensions.ServiceFabricGuest.Abstractions", "src\ServiceFabricGuest.Abstractions\Microsoft.Omex.Extensions.ServiceFabricGuest.Abstractions.csproj", "{A07BF64C-1B19-4972-83DB-B22BFF26E6B0}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore", "src\Diagnostics.HealthChecks.AspNetCore\Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore.csproj", "{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore.UnitTests", "tests\Diagnostics.HealthChecks.AspNetCore.UnitTests\Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore.UnitTests.csproj", "{43CE835D-5A71-4689-9297-942EF1233175}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -246,6 +250,22 @@ Global
 		{A07BF64C-1B19-4972-83DB-B22BFF26E6B0}.Release|Any CPU.Build.0 = Release|Any CPU
 		{A07BF64C-1B19-4972-83DB-B22BFF26E6B0}.Release|x64.ActiveCfg = Release|Any CPU
 		{A07BF64C-1B19-4972-83DB-B22BFF26E6B0}.Release|x64.Build.0 = Release|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Debug|x64.Build.0 = Debug|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Release|x64.ActiveCfg = Release|Any CPU
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD}.Release|x64.Build.0 = Release|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Debug|x64.Build.0 = Debug|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Release|Any CPU.Build.0 = Release|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Release|x64.ActiveCfg = Release|Any CPU
+		{43CE835D-5A71-4689-9297-942EF1233175}.Release|x64.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -272,6 +292,8 @@ Global
 		{8520AA74-FDA7-4EC0-B60D-C9A786574443} = {3249ADDB-50EC-4C21-A8F0-65EF444662EE}
 		{E9123DDF-3D31-48A5-8442-F1DAD516E1A6} = {551C93F8-6E89-4954-8905-7F5AC7173285}
 		{A07BF64C-1B19-4972-83DB-B22BFF26E6B0} = {3249ADDB-50EC-4C21-A8F0-65EF444662EE}
+		{7FD8C746-9DB1-4B33-B4A6-95AF5FEF2CCD} = {3249ADDB-50EC-4C21-A8F0-65EF444662EE}
+		{43CE835D-5A71-4689-9297-942EF1233175} = {551C93F8-6E89-4954-8905-7F5AC7173285}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {E6FB7BCB-BF07-4F19-ACBA-457479D421BB}

src/Diagnostics.HealthChecks.AspNetCore/ActivityMarkersExtensions.cs

@@ -0,0 +1,46 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+
+using System;
+using System.Diagnostics;
+
+namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore;
+
+/// <summary>
+/// A set of extensions for Activity markers.
+/// </summary>
+public static class ActivityMarkersExtensions
+{
+	/// <summary>
+	/// The key used to identify the Short Circuited Activity.
+	/// </summary>
+	public const string LivenessCheckActivityKey = "LivenessCheckMarker";
+
+	/// <summary>
+	/// The value used to identify the Short Circuited Activity.
+	/// </summary>
+	public const string LivenessCheckActivityValue = "true";
+
+	/// <summary>
+	/// Determines whether the activity has been marked as belonging to a health check whose call should be
+	/// short-circuited.
+	/// </summary>
+	/// <param name="activity">The Activity.</param>
+	/// <returns><c>True</c> if the activity's health check should be short-circuited, <c>False</c> otherwise.</returns>
+	public static bool IsLivenessCheck(this Activity activity) =>
+		string.Equals(activity.GetBaggageItem(LivenessCheckActivityKey), LivenessCheckActivityValue, StringComparison.OrdinalIgnoreCase);
+
+	/// <summary>
+	/// Marks the Activity as belonging to a liveness health check whose call should be short-circuited.
+	/// </summary>
+	/// <param name="activity">The activity.</param>
+	/// <returns>The marked activity.</returns>
+	public static Activity MarkAsLivenessCheck(this Activity activity)
+	{
+		if (!activity.IsLivenessCheck())
+		{
+			return activity.AddBaggage(LivenessCheckActivityKey, LivenessCheckActivityValue);
+		}
+
+		return activity;
+	}
+}

src/Diagnostics.HealthChecks.AspNetCore/HealthCheckComposablesExtensions.cs

@@ -0,0 +1,37 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+
+using System;
+using System.Diagnostics;
+using System.Net.Http;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore;
+
+/// <summary>
+/// Extension methods for health check decorators configuration.
+/// </summary>
+public static class HealthCheckComposablesExtensions
+{
+	/// <summary>
+	/// Creates a new liveness HTTP endpoint checker health check.
+	/// This health check will only verify the reachability of the endpoint, it will mark the activity as a liveness activity,
+	/// that can trigger the response short-circuiting.
+	/// </summary>
+	/// <param name="requestBuilder">The request builder.</param>
+	/// <param name="activitySource">The activity source.</param>
+	/// <param name="httpClientFactory">The http client factory.</param>
+	/// <param name="httpClientName">The HTTP Client name, if a client with that name was registered in particular.</param>
+	/// <returns>The HTTP endpoint checker health check.</returns>
+	public static IHealthCheck CreateLivenessHttpHealthCheck(
+		Func<HttpRequestMessage> requestBuilder,
+		ActivitySource activitySource,
+		IHttpClientFactory httpClientFactory,
+		string? httpClientName = "") =>
+			Composables.HealthCheckComposablesExtensions.CreateHttpHealthCheck(
+				requestBuilder,
+				async (context, response, _) => await Composables.HealthCheckComposablesExtensions.CheckResponseStatusCodeAsync(context, response),
+				activitySource,
+				httpClientFactory,
+				httpClientName: httpClientName,
+				activityMarker: activity => activity?.MarkAsLivenessCheck());
+}

src/Diagnostics.HealthChecks.AspNetCore/LivenessCheckActionFilterAttribute.cs

@@ -0,0 +1,23 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+
+using System.Diagnostics;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Filters;
+
+namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore;
+
+/// <summary>
+/// This endpoint filter tries to identify whether the current <seealso cref="Activity"/> has been marked
+/// as a Liveness health check. If it is, it returns a 200 response.
+/// </summary>
+public class LivenessCheckActionFilterAttribute : ActionFilterAttribute
+{
+	/// <inheritdoc />
+	public override void OnActionExecuting(ActionExecutingContext context)
+	{
+		if (Activity.Current?.IsLivenessCheck() == true)
+		{
+			context.Result = new OkObjectResult("Running test healthcheck transaction");
+		}
+	}
+}

src/Diagnostics.HealthChecks.AspNetCore/Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore.csproj

@@ -0,0 +1,20 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <TargetFrameworks>$(NetCoreVersions)</TargetFrameworks>
+    <PlatformTarget>x64</PlatformTarget>
+  </PropertyGroup>
+  <PropertyGroup Label="NuGet Properties">
+    <Title>Microsoft.Omex.Extensions.Diagnostics.HealthChecks.AspNetCore</Title>
+    <Summary>Microsoft Omex Extensions Diagnostics HealthChecks.AspNetCore</Summary>
+    <Description>This library adds support to Omex Health Checks to ASP.NET Core controllers.</Description>
+    <ReleaseNotes>Initial release.</ReleaseNotes>
+    <PackageProjectUrl>https://github.com/microsoft/Omex/tree/main/src/Extensions/Diagnostics.HealthChecks</PackageProjectUrl>
+    <PackageTags>Microsoft;Omex;Extensions;HealthChecks;AspNetCore</PackageTags>
+  </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.AspNetCore.Mvc.Core" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\Diagnostics.HealthChecks\Microsoft.Omex.Extensions.Diagnostics.HealthChecks.csproj" />
+  </ItemGroup>
+</Project>

src/Diagnostics.HealthChecks/AbstractHealthCheck.cs

@@ -15,6 +15,7 @@ namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks
 	/// <summary>
 	/// Base health check that extracts logic of exception handling and wraps it into activity
 	/// </summary>
+	[Obsolete("The usage of this class is deprecated and will be removed in a later release, please use composable classes in Microsoft.Omex.Extensions.Diagnostics.HealthChecks.Composables namespace to build health checks.")]
 	public abstract class AbstractHealthCheck<TParameters> : IHealthCheck
 		where TParameters : HealthCheckParameters
 	{
@@ -43,7 +44,7 @@ protected AbstractHealthCheck(TParameters parameters, ILogger logger, ActivitySo
 		/// <inheritdoc />
 		public async Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken token = default)
 		{
-			string activityName = string.IsNullOrWhiteSpace(context.Registration.Name) ? "HealthCheckActivity" : context.Registration.Name; 
+			string activityName = string.IsNullOrWhiteSpace(context.Registration.Name) ? "HealthCheckActivity" : context.Registration.Name;
 			using Activity? activity = m_activitySource.StartActivity(activityName)
 				?.MarkAsSystemError()
 				.MarkAsHealthCheck();

src/Diagnostics.HealthChecks/Composables/HealthCheckComposablesExtensions.cs

@@ -0,0 +1,113 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+
+using System;
+using System.Diagnostics;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Caching.Memory;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks.Composables;
+
+/// <summary>
+/// Extension methods for health check decorators configuration.
+/// </summary>
+public static class HealthCheckComposablesExtensions
+{
+	/// <summary>
+	/// Makes the Health check executable only at startup time, adding also observability to it.
+	/// If the consumer health check of this extension method does not want automatic observability,
+	/// the developer is encouraged to wrap it directly around the <see cref="StartupHealthCheck"/> class.
+	/// </summary>
+	/// <param name="healthCheck">The health check.</param>
+	/// <param name="cache">The memory cache. It will be used to memorise the latest health check result.</param>
+	/// <param name="activitySource">The activity source.</param>
+	/// <param name="logger">The logger.</param>
+	/// <param name="parameters">The health check parameters, set at DI registration time.</param>
+	/// <returns>The health check executable only at deploy time.</returns>
+	public static IHealthCheck AsObservableStartupHealthCheck(
+		this IHealthCheck healthCheck,
+		IMemoryCache cache,
+		ActivitySource activitySource,
+		ILogger logger,
+		HealthCheckParameters? parameters = null)
+	{
+		IHealthCheck startupHealthCheck = new StartupHealthCheck(healthCheck, cache);
+		return new ObservableHealthCheck(parameters ?? new(), startupHealthCheck, activitySource, logger);
+	}
+
+	/// <summary>
+	/// Applies the default error handling and activity around the current health check.
+	/// </summary>
+	/// The instance of the Activity marker. By selecting the implementor, the health check will determine how
+	/// the related endpoint will process the health check request.
+	/// <param name="healthCheck">The health check.</param>
+	/// <param name="activitySource">The activity source.</param>
+	/// <param name="logger">The logger.</param>
+	/// <param name="parameters">The health check parameters, set at DI registration time.</param>
+	/// <returns>The health check with the default configuration and error handling.</returns>
+	public static IHealthCheck AsObservableHealthCheck(
+		this IHealthCheck healthCheck,
+		ActivitySource activitySource,
+		ILogger logger,
+		HealthCheckParameters? parameters = null) =>
+		new ObservableHealthCheck(parameters ?? new(), healthCheck, activitySource, logger);
+
+	/// <summary>
+	/// Creates a new HTTP endpoint checker health check.
+	/// </summary>
+	/// <param name="httpClientFactory">The http client factory.</param>
+	/// <param name="requestBuilder">The request builder.</param>
+	/// <param name="healthCheckResponseChecker">The response checker instance.</param>
+	/// <param name="activitySource">The activity source.</param>
+	/// <param name="httpClientName">The HTTP Client name, if a client with that name was registered in particular.</param>
+	/// <param name="activityMarker">Marks the activity with the required baggage items.</param>
+	/// <returns>The HTTP endpoint checker health check.</returns>
+	public static IHealthCheck CreateHttpHealthCheck(
+		Func<HttpRequestMessage> requestBuilder,
+		Func<HealthCheckContext, HttpResponseMessage, CancellationToken, Task<HealthCheckResult>> healthCheckResponseChecker,
+		ActivitySource activitySource,
+		IHttpClientFactory httpClientFactory,
+		string? httpClientName = "",
+		Action<Activity?>? activityMarker = null) =>
+			new HttpEndpointHealthCheck(
+				httpClientFactory,
+				requestBuilder,
+				healthCheckResponseChecker,
+				activitySource,
+				httpClientName: httpClientName,
+				activityMarker: activityMarker);
+
+	/// <summary>
+	/// Checks whether the response from the endpoint is successful or not by checking its HTTP Status Code.
+	/// </summary>
+	/// <param name="context">The Health Check Context.</param>
+	/// <param name="response">The endpoint response.</param>
+	/// <param name="allowedStatusCodes">The allowed status codes for the response..</param>
+	/// <returns>The health check result.</returns>
+	public static async Task<HealthCheckResult> CheckResponseStatusCodeAsync(
+		HealthCheckContext context,
+		HttpResponseMessage response,
+		HttpStatusCode[]? allowedStatusCodes = null)
+	{
+		if (allowedStatusCodes == null || allowedStatusCodes.Length == 0)
+		{
+			allowedStatusCodes = new[] { HttpStatusCode.OK };
+		}
+
+		if (allowedStatusCodes.Contains(response.StatusCode))
+		{
+			return await Task.FromResult(new HealthCheckResult(HealthStatus.Healthy, "The endpoint returned an allowed status code."));
+		}
+
+		return await Task.FromResult(
+			new HealthCheckResult(
+				context.Registration.FailureStatus,
+				$"The endpoint returned an unallowed status code. Status code returned: '{response.StatusCode}'. " +
+				$"Allowed status codes: '{string.Join(", ", allowedStatusCodes.Select(h => h.ToString()))}'"));
+	}
+}

src/Diagnostics.HealthChecks/Composables/HealthCheckConstants.cs

@@ -0,0 +1,14 @@
+// Copyright (C) Microsoft Corporation. All rights reserved.
+
+namespace Microsoft.Omex.Extensions.Diagnostics.HealthChecks.Composables;
+
+/// <summary>
+/// A series of constants used by health checks.
+/// </summary>
+public static class HealthCheckConstants
+{
+	/// <summary>
+	/// The local service default host.
+	/// </summary>
+	public const string LocalServiceDefaultHost = "localhost";
+}