added missing health check endpoint in AuditWriter

Author: hardik-desai-nhs

application/CohortManager/src/Functions/AuditServices/AuditWriter/AuditWriter.csproj

@@ -9,6 +9,7 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Microsoft.Azure.Functions.Worker" />
+    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Http" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.ServiceBus" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" />
     <PackageReference Include="Microsoft.Extensions.Diagnostics.HealthChecks" />

application/CohortManager/src/Functions/AuditServices/AuditWriter/HealthCheckFunction.cs

@@ -0,0 +1,23 @@
+namespace NHS.CohortManager.AuditServices;
+
+using System.Threading.Tasks;
+using HealthChecks.Extensions;
+using Microsoft.Azure.Functions.Worker;
+using Microsoft.Azure.Functions.Worker.Http;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+public class HealthCheckFunction
+{
+    private readonly HealthCheckService _healthCheckService;
+
+    public HealthCheckFunction(HealthCheckService healthCheckService)
+    {
+        _healthCheckService = healthCheckService;
+    }
+
+    [Function("health")]
+    public async Task<HttpResponseData> Run([HttpTrigger(AuthorizationLevel.Anonymous, "get")] HttpRequestData req)
+    {
+        return await HealthCheckServiceExtensions.CreateHealthCheckResponseAsync(req, _healthCheckService);
+    }
+}