(NCIOCPL#17) Add aHealthcheck

integration-tests/features/healthcheck/status.feature

@@ -0,0 +1,11 @@
+Feature: The system is able to report whether it is a healthy condition.
+
+  Background:
+    * url apiHost
+
+  Scenario: The index has been loaded.
+
+    Given path 'HealthCheck', 'status'
+    When method get
+    Then status 200
+    And match response == 'alive!'

src/NCI.OCPL.Api.ResourcesForResearchers/Controllers/HealthCheckController.cs

@@ -0,0 +1,68 @@
+using System;
+using System.Threading.Tasks;
+
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+
+using NCI.OCPL.Api.Common;
+
+
+namespace NCI.OCPL.Api.ResourcesForResearchers.Controllers
+{
+
+  /// <summary>
+  /// Controller for reporting on system health.
+  /// </summary>
+  [Route("HealthCheck")]
+  public class HealthCheckController : ControllerBase
+  {
+
+    /// <summary>
+    /// Message to return for a "healthy" status.
+    /// </summary>
+    public const string HEALTHY_STATUS = "alive!";
+
+    /// <summary>
+    /// Message to return for an "unhealthy" status.
+    /// </summary>
+    public const string UNHEALTHY_STATUS = "Service not healthy.";
+
+    private readonly IHealthCheckService _healthSvc;
+    private readonly ILogger _logger;
+
+    /// <summary>
+    /// Constructor.
+    /// </summary>
+    /// <param name="logger">The logger.</param>
+    /// <param name="healthCheckSvc">Elasticsearch health check instance.</param>
+    /// <returns></returns>
+    public HealthCheckController(ILogger<HealthCheckController> logger, IHealthCheckService healthCheckSvc)
+      => (_logger, _healthSvc) = (logger, healthCheckSvc);
+
+
+    /// <summary>
+    /// Provides an endpoint for checking that the glossary API and underlying Elasticsearch instance
+    /// are in a good operational state.
+    /// </summary>
+    /// <returns>Status 200 and the message "alive!" if the service is healthy.
+    ///
+    /// Status 500  and the message "Service not healthy." otherwise.</returns>
+    [HttpGet("status")]
+    public async Task<string> IsHealthy()
+    {
+      try
+      {
+          bool isHealthy = await _healthSvc.IndexIsHealthy(); ;
+          if (isHealthy)
+              return HEALTHY_STATUS;
+          else
+              throw new APIErrorException(500, UNHEALTHY_STATUS);
+      }
+      catch (Exception ex)
+      {
+          _logger.LogError(ex, "Error checking health.");
+          throw new APIErrorException(500, UNHEALTHY_STATUS);
+      }
+    }
+  }
+}

src/NCI.OCPL.Api.ResourcesForResearchers/NCI.OCPL.Api.ResourcesForResearchers.csproj

@@ -14,7 +14,7 @@
 
   <ItemGroup>
     <PackageReference Include="Elasticsearch.Net" Version="7.9.*" />
-    <PackageReference Include="NCI.OCPL.Api.Common" Version="2.0.*" />
+    <PackageReference Include="NCI.OCPL.Api.Common" Version="2.1.*" />
     <PackageReference Include="NSwag.AspNetCore" Version="13.11.*" />
     <PackageReference Include="NEST" Version="7.9.*" />
   </ItemGroup>

src/NCI.OCPL.Api.ResourcesForResearchers/Startup.cs

@@ -59,6 +59,13 @@ protected override void AddAppServices(IServiceCollection services)
             services.AddSingleton<IResourceAggregationService, ESResourceAggregationService>();
 
             services.Configure<R4RAPIOptions>(Configuration.GetSection("R4RAPI"));
+
+            // Get name for the Healthcheck alias.
+            services.AddTransient<IESAliasNameProvider>(p =>
+            {
+                string alias = Configuration["R4RAPI:AliasName"];
+                return new ESAliasNameProvider() { Name = alias };
+            });
         }
 
 

test/NCI.OCPL.Api.ResourcesForResearchers.Tests/NCI.OCPL.Api.ResourcesForResearchers.Tests.csproj

@@ -17,8 +17,8 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="NCI.OCPL.Api.Common" Version="2.0.*" />
-    <PackageReference Include="NCI.OCPL.Api.Common.Testing" Version="2.0.*" />
+    <PackageReference Include="NCI.OCPL.Api.Common" Version="2.1.*" />
+    <PackageReference Include="NCI.OCPL.Api.Common.Testing" Version="2.1.*" />
   </ItemGroup>
 
   <ItemGroup>

test/NCI.OCPL.Api.ResourcesForResearchers.Tests/Tests/Controllers/HealthCheckControllerTests.cs

@@ -0,0 +1,87 @@
+using System;
+
+using Microsoft.Extensions.Logging.Testing;
+
+using Moq;
+using Xunit;
+
+using NCI.OCPL.Api.Common;
+using NCI.OCPL.Api.ResourcesForResearchers.Controllers;
+
+
+namespace NCI.OCPL.Api.Glossary.Tests
+{
+  public class HealthCheckControllerTests
+  {
+    /// <summary>
+    /// Handle the healthcheck reporting an unhealthy status.
+    /// </summary>
+    [Fact]
+    public async void IsUnhealthy()
+    {
+      var logger = NullLogger<HealthCheckController>.Instance;
+      var healthcheckService = new Mock<IHealthCheckService>();
+      healthcheckService.Setup(
+        svc => svc.IndexIsHealthy()
+      )
+      .ReturnsAsync(false);
+
+      var controller = new HealthCheckController(logger, healthcheckService.Object);
+
+      var exception = await Assert.ThrowsAsync<APIErrorException>(() => controller.IsHealthy());
+
+      Assert.Equal(500, exception.HttpStatusCode);
+      Assert.Equal(HealthCheckController.UNHEALTHY_STATUS, exception.Message);
+    }
+
+
+    /// <summary>
+    /// Handle the health service failing.
+    /// </summary>
+    [Fact]
+    public async void IsVeryUnhealthy()
+    {
+      var logger = NullLogger<HealthCheckController>.Instance;
+      var healthcheckService = new Mock<IHealthCheckService>();
+      healthcheckService.Setup(
+        svc => svc.IndexIsHealthy()
+      )
+      .ThrowsAsync(new Exception("kaboom!"));
+
+
+      var controller = new HealthCheckController(logger, healthcheckService.Object);
+
+      var exception = await Assert.ThrowsAsync<APIErrorException>(() => controller.IsHealthy());
+
+      Assert.Equal(500, exception.HttpStatusCode);
+      Assert.Equal(HealthCheckController.UNHEALTHY_STATUS, exception.Message);
+    }
+
+
+    /// <summary>
+    /// Handle the healthcheck reporting a healthy status.
+    /// </summary>
+    [Fact]
+    public async void IsHealthy()
+    {
+      var logger = NullLogger<HealthCheckController>.Instance;
+      var healthcheckService = new Mock<IHealthCheckService>();
+      healthcheckService.Setup(
+        healthSvc => healthSvc.IndexIsHealthy()
+      )
+      .ReturnsAsync(true);
+
+      var controller = new HealthCheckController(logger, healthcheckService.Object);
+
+      string actual = await controller.IsHealthy();
+
+      healthcheckService.Verify(
+        svc => svc.IndexIsHealthy(),
+        Times.Once
+      );
+
+      Assert.Equal(HealthCheckController.HEALTHY_STATUS, actual);
+    }
+
+  }
+}