feat: Enable health checks and add health check around the configuration

Merge pull request #293 from DFE-Digital/feat/add-healthcheck

Childrens-Social-Care-CPD-Tests/ConfigurationHealthCheckTests.cs

@@ -0,0 +1,165 @@
+using Castle.Core.Logging;
+using Childrens_Social_Care_CPD;
+using Childrens_Social_Care_CPD.Configuration;
+using FluentAssertions;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+using Microsoft.Extensions.Logging;
+using NSubstitute;
+using NSubstitute.Extensions;
+using NUnit.Framework;
+using System.Threading.Tasks;
+
+namespace Childrens_Social_Care_CPD_Tests;
+
+public class ConfigurationHealthCheckTests
+{
+    private ILogger<ConfigurationHealthCheck> _logger;
+    private IApplicationConfiguration _applicationConfiguration;
+
+    [SetUp]
+    public void Setup()
+    {
+        _logger = Substitute.For<ILogger<ConfigurationHealthCheck>>();
+        _applicationConfiguration = Substitute.For<IApplicationConfiguration>();
+        _applicationConfiguration.ReturnsForAll("foo");
+    }
+
+    [Test]
+    public async Task Passes_When_All_Values_Set_And_Cookies_Are_Secured()
+    {
+        // arrange
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Healthy);
+    }
+
+    [Test]
+    public async Task Fails_When_Disable_Cookies_Is_True()
+    {
+        // arrange
+        _applicationConfiguration.DisableSecureCookies.Returns(true);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_AppInsightsConnectionString_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.AppInsightsConnectionString.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_AppVersion_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.AppVersion.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_AzureEnvironment_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.AzureEnvironment.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_ClarityProjectId_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.ClarityProjectId.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_ContentfulDeliveryApiKey_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.ContentfulDeliveryApiKey.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_ContentfulEnvironment_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.ContentfulEnvironment.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_ContentfulSpaceId_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.ContentfulSpaceId.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+
+    [Test]
+    public async Task Fails_When_GoogleTagManagerKey_Is_Not_Set()
+    {
+        // arrange
+        _applicationConfiguration.GoogleTagManagerKey.Returns(string.Empty);
+        var sut = new ConfigurationHealthCheck(_logger, _applicationConfiguration);
+
+        // act
+        var result = await sut.CheckHealthAsync(null, default);
+
+        // assert
+        result.Status.Should().Be(HealthStatus.Unhealthy);
+    }
+}

Childrens-Social-Care-CPD/ConfigurationHealthCheck.cs

@@ -0,0 +1,52 @@
+using Childrens_Social_Care_CPD.Configuration;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace Childrens_Social_Care_CPD;
+
+public class ConfigurationHealthCheck : IHealthCheck
+{
+    private readonly ILogger _logger;
+    private readonly IApplicationConfiguration _applicationConfiguration;
+
+    public ConfigurationHealthCheck(ILogger<ConfigurationHealthCheck> logger, IApplicationConfiguration applicationConfiguration)
+    {
+        _logger = logger;
+        _applicationConfiguration = applicationConfiguration;
+    }
+
+    private bool CheckSetting(string name, string value)
+    {
+        if (string.IsNullOrWhiteSpace(value))
+        {
+            _logger.LogError("Configuration setting {propertyName} does not have a value", name);
+            return false;
+        }
+
+        return true;
+    }
+
+    public Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
+    {
+        var healthy = CheckSetting("AppInsightsConnectionString", _applicationConfiguration.AppInsightsConnectionString)
+            && CheckSetting("AppVersion", _applicationConfiguration.AppVersion)
+            && CheckSetting("AzureEnvironment", _applicationConfiguration.AzureEnvironment)
+            && CheckSetting("ClarityProjectId", _applicationConfiguration.ClarityProjectId)
+            && CheckSetting("ContentfulDeliveryApiKey", _applicationConfiguration.ContentfulDeliveryApiKey)
+            && CheckSetting("ContentfulEnvironment", _applicationConfiguration.ContentfulEnvironment)
+            && CheckSetting("ContentfulSpaceId", _applicationConfiguration.ContentfulSpaceId)
+            && CheckSetting("GoogleTagManagerKey", _applicationConfiguration.GoogleTagManagerKey);
+
+        if (_applicationConfiguration.DisableSecureCookies)
+        {
+            _logger.LogError("DisableSecureCookies should not be enabled for standard environments");
+            healthy = false;
+        }
+
+        if (!healthy)
+        {
+            return Task.FromResult(HealthCheckResult.Unhealthy("One or more application configuration settings is missing or incorrect"));
+        }
+
+        return Task.FromResult(HealthCheckResult.Healthy("Application configuration is OK"));
+    }
+}

Childrens-Social-Care-CPD/Program.cs

@@ -24,6 +24,8 @@
 app.MapControllerRoute(
     name: "default",
     pattern: "{controller=Content}/{action=Index}");
+app.MapHealthChecks("application/status");
+
 
 app.Run();
 

Childrens-Social-Care-CPD/WebApplicationBuilderExtensions.cs

@@ -74,5 +74,7 @@ public static void AddFeatures(this WebApplicationBuilder builder)
                 options.Rules.Insert(0, new LoggerFilterRule(typeof(ApplicationInsightsLoggerProvider).FullName, null, LogLevel.Information, null));
             }
         });
+
+        builder.Services.AddHealthChecks().AddCheck<ConfigurationHealthCheck>("Configuration Health Check", tags: new[] {"configuration"});
     }
 }