Add ClickHouse HealthCheck support (#2315)

smbecker · adamsitnik · web-flow · commit e8730dbffdc2 · 2024-12-11T17:10:58.000+01:00
Co-authored-by: Adam Sitnik &lt;adam.sitnik@gmail.com&gt;
diff --git a/.env b/.env
@@ -20,4 +20,7 @@ FTP_PORT=21
 FTP_USER=bob
 FTP_PASS=12345
 RAVENDB_PORT=9030
-SOLR_PORT=8983
+SOLR_PORT=8983
+CLICKHOUSE_USER=default
+CLICKHOUSE_PASSWORD=Password12!
+CLICKHOUSE_PORT=8123
diff --git a/.github/codecov.yml b/.github/codecov.yml
@@ -31,6 +31,8 @@ flags:
     carryforward: true
   AzureStorage:
     carryforward: true
+  ClickHouse:
+    carryforward: true
   Consul:
     carryforward: true
   CosmosDb:
diff --git a/.github/labeler.yml b/.github/labeler.yml
@@ -36,6 +36,9 @@ azure:
   - changed-files:
     - any-glob-to-any-file: [src/HealthChecks.Azure*/**/*]
 
+clickhouse:
+  - src/HealthChecks.ClickHouse/**/*
+
 consul:
   - changed-files:
     - any-glob-to-any-file: [src/HealthChecks.Consul/**/*]
diff --git a/.github/workflows/healthchecks_clickhouse_cd.yml b/.github/workflows/healthchecks_clickhouse_cd.yml
@@ -0,0 +1,16 @@
+name: HealthChecks ClickHouse DB CD
+
+on:
+  push:
+    tags:
+      - release-clickhouse-*
+      - release-all-*
+
+jobs:
+  build:
+    uses: ./.github/workflows/reusable_cd_workflow.yml
+    secrets: inherit
+    with:
+      BUILD_CONFIG: Release
+      PROJECT_PATH: ./src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj
+      PACKAGE_NAME: AspNetCore.HealthChecks.ClickHouse
diff --git a/.github/workflows/healthchecks_clickhouse_cd_preview.yml b/.github/workflows/healthchecks_clickhouse_cd_preview.yml
@@ -0,0 +1,17 @@
+name: HealthChecks ClickHouse DB Preview CD
+
+on:
+  push:
+    tags:
+      - preview-clickhouse-*
+      - preview-all-*
+
+jobs:
+  build:
+    uses: ./.github/workflows/reusable_cd_preview_workflow.yml
+    secrets: inherit
+    with:
+      BUILD_CONFIG: Release
+      VERSION_SUFFIX_PREFIX: rc1
+      PROJECT_PATH: ./src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj
+      PACKAGE_NAME: AspNetCore.HealthChecks.ClickHouse
diff --git a/.github/workflows/healthchecks_clickhouse_ci.yml b/.github/workflows/healthchecks_clickhouse_ci.yml
@@ -0,0 +1,77 @@
+name: HealthChecks ClickHouse DB CI
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ master ]
+    paths:
+      - src/HealthChecks.ClickHouse/**
+      - test/HealthChecks.ClickHouse.Tests/**
+      - test/_SHARED/**
+      - .github/workflows/healthchecks_clickhouse_ci.yml
+      - Directory.Build.props
+      - Directory.Build.targets
+      - Directory.Packages.props
+    tags-ignore:
+      - release-*
+      - preview-*
+
+  pull_request:
+    branches: [ master ]
+    paths:
+      - src/HealthChecks.ClickHouse/**
+      - test/HealthChecks.ClickHouse.Tests/**
+      - test/_SHARED/**
+      - .github/workflows/healthchecks_clickhouse_ci.yml
+      - Directory.Build.props
+      - Directory.Build.targets
+      - Directory.Packages.props
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    services:
+      clickhouse:
+        image: clickhouse/clickhouse-server:24-alpine
+        ports:
+          - 8123:8123
+        env:
+          CLICKHOUSE_DB: default
+          CLICKHOUSE_USER: default
+          CLICKHOUSE_PASSWORD: "Password12!"
+          CLICKHOUSE_DEFAULT_ACCESS_MANAGEMENT: "1"
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup .NET
+        uses: actions/setup-dotnet@v4
+        with:
+          dotnet-version: |
+            8.0.x
+            9.0.x
+      - name: Restore
+        run: |
+          dotnet restore ./src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj &&
+          dotnet restore ./test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj
+      - name: Check formatting
+        run: |
+          dotnet format --no-restore --verify-no-changes --severity warn ./src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj || (echo "Run 'dotnet format' to fix issues" && exit 1) &&
+          dotnet format --no-restore --verify-no-changes --severity warn ./test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj || (echo "Run 'dotnet format' to fix issues" && exit 1)
+      - name: Build
+        run: |
+          dotnet build --no-restore ./src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj &&
+          dotnet build --no-restore ./test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj
+      - name: Test
+        run: >
+          dotnet test
+          ./test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj
+          --no-restore
+          --no-build
+          --collect "XPlat Code Coverage"
+          --results-directory .coverage
+          --
+          DataCollectionRunSettings.DataCollectors.DataCollector.Configuration.Format=opencover
+      - name: Upload Coverage
+        uses: codecov/codecov-action@v3
+        with:
+          flags: ClickHouse
+          directory: .coverage
diff --git a/AspNetCore.Diagnostics.HealthChecks.sln b/AspNetCore.Diagnostics.HealthChecks.sln
@@ -315,6 +315,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HealthChecks.Rabbitmq.v6",
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HealthChecks.RabbitMQ.v6.Tests", "test\HealthChecks.RabbitMQ.v6.Tests\HealthChecks.RabbitMQ.v6.Tests.csproj", "{2787F63E-ABEA-9461-CDF3-97FE7C5C3DCC}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HealthChecks.ClickHouse", "src\HealthChecks.ClickHouse\HealthChecks.ClickHouse.csproj", "{96E2B0A3-02BD-456B-8888-4D96DABA99EB}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "HealthChecks.ClickHouse.Tests", "test\HealthChecks.ClickHouse.Tests\HealthChecks.ClickHouse.Tests.csproj", "{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -881,6 +885,14 @@ Global
 		{2787F63E-ABEA-9461-CDF3-97FE7C5C3DCC}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{2787F63E-ABEA-9461-CDF3-97FE7C5C3DCC}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{2787F63E-ABEA-9461-CDF3-97FE7C5C3DCC}.Release|Any CPU.Build.0 = Release|Any CPU
+		{96E2B0A3-02BD-456B-8888-4D96DABA99EB}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{96E2B0A3-02BD-456B-8888-4D96DABA99EB}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{96E2B0A3-02BD-456B-8888-4D96DABA99EB}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{96E2B0A3-02BD-456B-8888-4D96DABA99EB}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -1026,6 +1038,8 @@ Global
 		{D49CF52C-9D21-4D98-8A15-A2B259E9C003} = {FF4414C2-8863-4ADA-8A1D-4B9F25C361FE}
 		{C76D7349-A3D2-7277-93C6-EE92E8E447A5} = {2A3FD988-2BB8-43CF-B3A2-B70E648259D4}
 		{2787F63E-ABEA-9461-CDF3-97FE7C5C3DCC} = {FF4414C2-8863-4ADA-8A1D-4B9F25C361FE}
+		{96E2B0A3-02BD-456B-8888-4D96DABA99EB} = {2A3FD988-2BB8-43CF-B3A2-B70E648259D4}
+		{2FB5CB9F-F870-48DE-BD1D-306AE86A67CA} = {FF4414C2-8863-4ADA-8A1D-4B9F25C361FE}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {2B8C62A1-11B6-469F-874C-A02443256568}
diff --git a/Directory.Packages.props b/Directory.Packages.props
@@ -24,6 +24,7 @@
     <PackageVersion Include="Azure.Storage.Blobs" Version="12.19.1" />
     <PackageVersion Include="Azure.Storage.Files.Shares" Version="12.17.1" />
     <PackageVersion Include="Azure.Storage.Queues" Version="12.17.1" />
+    <PackageVersion Include="ClickHouse.Client" Version="7.8.2" />
     <PackageVersion Include="Confluent.Kafka" Version="2.3.0" />
     <PackageVersion Include="coverlet.collector" Version="6.0.0" />
     <PackageVersion Include="Dapr.Client" Version="1.12.0" />
diff --git a/README.md b/README.md
@@ -85,6 +85,7 @@ HealthChecks packages include health checks for:
 | Azure Key Vault            | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.AzureKeyVault)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureKeyVault)                       | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.AzureKeyVault)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureKeyVault) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/azure)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/azure)
 | Azure Search               | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.AzureSearch)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureSearch)                           | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.AzureSearch)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureSearch) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/azure)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/azure)
 | Azure Service Bus          | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.AzureServiceBus)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureServiceBus)                   | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.AzureServiceBus)](https://www.nuget.org/packages/AspNetCore.HealthChecks.AzureServiceBus) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/azure)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/azure) | Queue and Topics                                             |
+| ClickHouse                 | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.ClickHouse)](https://www.nuget.org/packages/AspNetCore.HealthChecks.ClickHouse)                                 | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.ClickHouse)](https://www.nuget.org/packages/AspNetCore.HealthChecks.ClickHouse) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/clickhouse)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/clickhouse)
 | Consul                     | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.Consul)](https://www.nuget.org/packages/AspNetCore.HealthChecks.Consul)                                     | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.Consul)](https://www.nuget.org/packages/AspNetCore.HealthChecks.Consul) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/consul)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/consul)
 | CosmosDb                   | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.CosmosDb)](https://www.nuget.org/packages/AspNetCore.HealthChecks.CosmosDb)                                 | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.CosmosDb)](https://www.nuget.org/packages/AspNetCore.HealthChecks.CosmosDb) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/cosmosdb)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/cosmosdb) | CosmosDb and Azure Table
 | Dapr                       | [![Nuget](https://img.shields.io/nuget/dt/AspNetCore.HealthChecks.Dapr)](https://www.nuget.org/packages/AspNetCore.HealthChecks.Dapr)                                         | [![Nuget](https://img.shields.io/nuget/v/AspNetCore.HealthChecks.Dapr)](https://www.nuget.org/packages/AspNetCore.HealthChecks.Dapr) | [![view](https://img.shields.io/github/issues/Xabaril/AspNetCore.Diagnostics.HealthChecks/dapr)](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/dapr)
@@ -143,6 +144,7 @@ Install-Package AspNetCore.HealthChecks.AzureKeyVault
 Install-Package AspNetCore.HealthChecks.AzureSearch
 Install-Package AspNetCore.HealthChecks.AzureServiceBus
 Install-Package AspNetCore.HealthChecks.AzureStorage
+Install-Package AspNetCore.HealthChecks.ClickHouse
 Install-Package AspNetCore.HealthChecks.Consul
 Install-Package AspNetCore.HealthChecks.CosmosDb
 Install-Package AspNetCore.HealthChecks.Dapr
@@ -703,4 +705,4 @@ answering [questions](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthCh
 2. Follow the code guidelines and conventions.
 3. New features are not only code, tests and documentation are also mandatory.
 4. PRs with [`Ups for grabs`](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/Ups%20for%20grabs)
-and [help wanted](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/help%20wanted) tags are good candidates to contribute. 
+and [help wanted](https://github.com/Xabaril/AspNetCore.Diagnostics.HealthChecks/labels/help%20wanted) tags are good candidates to contribute.
diff --git a/build/versions.props b/build/versions.props
@@ -18,6 +18,7 @@
     <HealthCheckAzureStorageBlobs>9.0.0</HealthCheckAzureStorageBlobs>
     <HealthCheckAzureStorageFilesShares>9.0.0</HealthCheckAzureStorageFilesShares>
     <HealthCheckAzureStorageQueues>9.0.0</HealthCheckAzureStorageQueues>
+    <HealthCheckClickHouse>9.0.0</HealthCheckClickHouse>
     <HealthCheckCloudFirestore>9.0.0</HealthCheckCloudFirestore>
     <HealthCheckConsul>9.0.0</HealthCheckConsul>
     <HealthCheckCosmosDb>9.0.0</HealthCheckCosmosDb>
diff --git a/docker-compose.yml b/docker-compose.yml
@@ -24,6 +24,15 @@ services:
         volumes:
             - ./build/docker-services/solrcore:/var/solr/data/solrcore
             - ./build/docker-services/solrcoredown:/var/solr/data/solrcoredown
+    clickhouse:
+        image: clickhouse/clickhouse-server:24-alpine
+        environment:
+            - CLICKHOUSE_DB=${CLICKHOUSE_USER}
+            - CLICKHOUSE_USER=${CLICKHOUSE_USER}
+            - CLICKHOUSE_PASSWORD=${CLICKHOUSE_PASSWORD}
+            - CLICKHOUSE_DEFAULT_ACCESS_MANAGEMENT="1"
+        ports:
+            - ${CLICKHOUSE_PORT}:8123
     postgres:
         image: postgres
         environment:
@@ -165,7 +174,7 @@ services:
         image: postgres
         ports:
         - "8010:5432"
-        environment: 
+        environment:
         - POSTGRES_USER=postgres
         - POSTGRES_PASSWORD=Password12!
     nats:
@@ -180,7 +189,7 @@ services:
         ports:
          - "8086:8086"
         environment:
-          DOCKER_INFLUXDB_INIT_MODE: setup 
+          DOCKER_INFLUXDB_INIT_MODE: setup
           DOCKER_INFLUXDB_INIT_USERNAME: ci_user
           DOCKER_INFLUXDB_INIT_PASSWORD: password
           DOCKER_INFLUXDB_INIT_ORG: influxdata
diff --git a/src/HealthChecks.ClickHouse/ClickHouseHealthCheck.cs b/src/HealthChecks.ClickHouse/ClickHouseHealthCheck.cs
@@ -0,0 +1,41 @@
+using ClickHouse.Client.ADO;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace HealthChecks.ClickHouse;
+
+/// <summary>
+/// A health check for ClickHouse databases.
+/// </summary>
+public class ClickHouseHealthCheck : IHealthCheck
+{
+    internal const string HEALTH_QUERY = "SELECT 1;";
+
+    private readonly ClickHouseConnection _connection;
+    private readonly string _command;
+
+    public ClickHouseHealthCheck(ClickHouseConnection connection, string command)
+    {
+        _connection = connection;
+        _command = command ?? HEALTH_QUERY;
+    }
+
+    /// <inheritdoc />
+    public async Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
+    {
+        try
+        {
+            await _connection.OpenAsync(cancellationToken).ConfigureAwait(false);
+
+            using var command = _connection.CreateCommand();
+            command.CommandText = _command;
+
+            await command.ExecuteScalarAsync(cancellationToken).ConfigureAwait(false);
+
+            return HealthCheckResult.Healthy();
+        }
+        catch (Exception ex)
+        {
+            return new HealthCheckResult(context.Registration.FailureStatus, description: ex.Message, exception: ex);
+        }
+    }
+}
diff --git a/src/HealthChecks.ClickHouse/DependencyInjection/ClickHouseHealthCheckBuilderExtensions.cs b/src/HealthChecks.ClickHouse/DependencyInjection/ClickHouseHealthCheckBuilderExtensions.cs
@@ -0,0 +1,47 @@
+using ClickHouse.Client.ADO;
+using HealthChecks.ClickHouse;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace Microsoft.Extensions.DependencyInjection;
+
+/// <summary>
+/// Extension methods to configure <see cref="ClickHouseHealthCheck"/>.
+/// </summary>
+public static class ClickHouseHealthCheckBuilderExtensions
+{
+    private const string NAME = "ClickHouse";
+
+    /// <summary>
+    /// Add a health check for ClickHouse databases.
+    /// </summary>
+    /// <param name="builder">The <see cref="IHealthChecksBuilder"/>.</param>
+    /// <param name="connectionFactory">A factory to build the ClickHouse connection to use.</param>
+    /// <param name="healthQuery">The query to be used in check.</param>
+    /// <param name="name">The health check name. Optional. If <c>null</c> the type name 'ClickHouse' will be used for the name.</param>
+    /// <param name="failureStatus">
+    /// The <see cref="HealthStatus"/> that should be reported when the health check fails. Optional. If <c>null</c> then
+    /// the default status of <see cref="HealthStatus.Unhealthy"/> will be reported.
+    /// </param>
+    /// <param name="tags">A list of tags that can be used to filter sets of health checks. Optional.</param>
+    /// <param name="timeout">An optional <see cref="TimeSpan"/> representing the timeout of the check.</param>
+    /// <returns>The specified <paramref name="builder"/>.</returns>
+    public static IHealthChecksBuilder AddClickHouse(
+        this IHealthChecksBuilder builder,
+        Func<IServiceProvider, ClickHouseConnection> connectionFactory,
+        string healthQuery = ClickHouseHealthCheck.HEALTH_QUERY,
+        string? name = default,
+        HealthStatus? failureStatus = default,
+        IEnumerable<string>? tags = default,
+        TimeSpan? timeout = default)
+    {
+        Guard.ThrowIfNull(connectionFactory);
+        Guard.ThrowIfNull(healthQuery);
+
+        return builder.Add(new HealthCheckRegistration(
+            name ?? NAME,
+            sp => new ClickHouseHealthCheck(connectionFactory(sp), healthQuery),
+            failureStatus,
+            tags,
+            timeout));
+    }
+}
diff --git a/src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj b/src/HealthChecks.ClickHouse/HealthChecks.ClickHouse.csproj
@@ -0,0 +1,14 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>netstandard2.1;$(DefaultNetCoreApp)</TargetFrameworks>
+    <PackageTags>$(PackageTags);Beat;ClickHouse</PackageTags>
+    <Description>HealthChecks.ClickHouse is a health check for ClickHouse.</Description>
+    <VersionPrefix>$(HealthCheckClickHouse)</VersionPrefix>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="ClickHouse.Client" />
+  </ItemGroup>
+
+</Project>
diff --git a/src/HealthChecks.ClickHouse/README.md b/src/HealthChecks.ClickHouse/README.md
@@ -0,0 +1,18 @@
+## ClickHouse Health Check
+
+This health check verifies the ability to communicate with [ClickHouse](https://www.clickhouse.com/). It uses the [ClickHouse.Client](https://www.nuget.org/packages/ClickHouse.Client) library.
+
+## Recommended approach
+
+When registering the ClickHouse health check, it is [recommended](https://github.com/DarkWanderer/ClickHouse.Client/wiki/Connection-lifetime-&-pooling#recommendations) to use `IHttpClientFactory` or a static instance of `HttpClient` to manage connections.
+
+```csharp
+void Configure(IServiceCollection services)
+{
+    services.AddHttpClient("ClickHouseClient");
+    services.AddHealthChecks().AddClickHouse(static sp => {
+        var httpClientFactory = sp.GetRequiredService<IHttpClientFactory>();
+        return new ClickHouseConnection("Host=ch;Username=default;Password=test;Database=default", httpClientFactory, "ClickHouseClient");
+    });
+}
+```
diff --git a/test/HealthChecks.ClickHouse.Tests/DependencyInjection/RegistrationTests.cs b/test/HealthChecks.ClickHouse.Tests/DependencyInjection/RegistrationTests.cs
diff --git a/test/HealthChecks.ClickHouse.Tests/Functional/ClickHouseHealthCheckTests.cs b/test/HealthChecks.ClickHouse.Tests/Functional/ClickHouseHealthCheckTests.cs
diff --git a/test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj b/test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.Tests.csproj
diff --git a/test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.approved.txt b/test/HealthChecks.ClickHouse.Tests/HealthChecks.ClickHouse.approved.txt
