EES-4389 - additional memory caching for the Themes endpoint that is …

…used by Find Stats page

src/GovUk.Education.ExploreEducationStatistics.Content.Api.Tests/Controllers/ThemeControllerCachingTests.cs

@@ -1,23 +1,97 @@
 #nullable enable
 using System;
 using System.Collections.Generic;
+using System.Threading.Tasks;
+using GovUk.Education.ExploreEducationStatistics.Common.Cache;
 using GovUk.Education.ExploreEducationStatistics.Common.Tests.Extensions;
 using GovUk.Education.ExploreEducationStatistics.Common.Tests.Fixtures;
+using GovUk.Education.ExploreEducationStatistics.Content.Api.Cache;
+using GovUk.Education.ExploreEducationStatistics.Content.Api.Controllers;
+using GovUk.Education.ExploreEducationStatistics.Content.Services.Interfaces;
+using GovUk.Education.ExploreEducationStatistics.Content.Services.Interfaces.Cache;
 using GovUk.Education.ExploreEducationStatistics.Content.Services.ViewModels;
+using Moq;
+using NCrontab;
 using Xunit;
+using static GovUk.Education.ExploreEducationStatistics.Common.Cache.CronSchedules;
 using static GovUk.Education.ExploreEducationStatistics.Common.Services.CollectionUtils;
+using static GovUk.Education.ExploreEducationStatistics.Common.Tests.Utils.MockUtils;
+using static Moq.MockBehavior;
 using static Newtonsoft.Json.JsonConvert;
 
 namespace GovUk.Education.ExploreEducationStatistics.Content.Api.Tests.Controllers;
 
 [Collection(CacheServiceTests)]
 public class ThemeControllerCachingTests : CacheServiceTestFixture
 {
+    private readonly IList<ThemeViewModel> _themes = ListOf(
+        new ThemeViewModel(Guid.NewGuid(), "slug1", "title1", "summary1"),
+        new ThemeViewModel(Guid.NewGuid(), "slug2", "title2", "summary2"));
+
+    [Fact]
+    public async Task ListThemes_NoCachedEntryExists()
+    {
+        var themeService = new Mock<IThemeService>(Strict);
+
+        MemoryCacheService
+            .Setup(s => s.GetItem(
+                new ListThemesCacheKey(),
+                typeof(IList<ThemeViewModel>)))
+            .Returns(null);
+
+        var expectedCacheConfiguration = new MemoryCacheConfiguration(
+            10, CrontabSchedule.Parse(HalfHourlyExpirySchedule));
+
+        MemoryCacheService
+            .Setup(s => s.SetItem<object>(
+                new ListThemesCacheKey(),
+                _themes,
+                ItIs.DeepEqualTo(expectedCacheConfiguration),
+                null));
+
+        themeService
+            .Setup(s => s.ListThemes())
+            .ReturnsAsync(_themes);
+
+        var controller = BuildController(themeService.Object);
+
+        var result = await controller.ListThemes();
+
+        VerifyAllMocks(MemoryCacheService, themeService);
+
+        Assert.Equal(_themes, result);
+    }
+
+    [Fact]
+    public async Task ListThemes_CachedEntryExists()
+    {
+        MemoryCacheService
+            .Setup(s => s.GetItem(
+                new ListThemesCacheKey(),
+                typeof(IList<ThemeViewModel>)))
+            .Returns(_themes);
+
+        var controller = BuildController();
+
+        var result = await controller.ListThemes();
+
+        VerifyAllMocks(MemoryCacheService);
+
+        Assert.Equal(_themes, result);
+    }
+
     [Fact]
     public void ThemeViewModelList_SerializeAndDeserialize()
     {
-        var themes = ListOf(new ThemeViewModel(Guid.NewGuid(), "slug", "title", "summary"));
-        var converted = DeserializeObject<List<ThemeViewModel>>(SerializeObject(themes));
-        converted.AssertDeepEqualTo(themes);
+        var converted = DeserializeObject<List<ThemeViewModel>>(SerializeObject(_themes));
+        converted.AssertDeepEqualTo(_themes);
+    }
+
+    private static ThemeController BuildController(IThemeService? themeService = null)
+    {
+        return new(
+            Mock.Of<IMethodologyCacheService>(),
+            themeService ?? Mock.Of<IThemeService>(Strict)
+        );
     }
 }

src/GovUk.Education.ExploreEducationStatistics.Content.Api/Cache/ListThemesCacheKey.cs

@@ -0,0 +1,8 @@
+using GovUk.Education.ExploreEducationStatistics.Common.Cache.Interfaces;
+
+namespace GovUk.Education.ExploreEducationStatistics.Content.Api.Cache;
+
+public record ListThemesCacheKey : IMemoryCacheKey
+{
+    public string Key => GetType().Name;
+}

src/GovUk.Education.ExploreEducationStatistics.Content.Api/Controllers/ThemeController.cs

@@ -36,7 +36,7 @@ public async Task<ActionResult<List<AllMethodologiesThemeViewModel>>> GetMethodo
                 .HandleFailuresOrOk();
         }
 
-        [MemoryCache(typeof(GetThemesCacheKey), durationInSeconds: 10, expiryScheduleCron: HalfHourlyExpirySchedule)]
+        [MemoryCache(typeof(ListThemesCacheKey), durationInSeconds: 10, expiryScheduleCron: HalfHourlyExpirySchedule)]
         [HttpGet("themes")]
         public async Task<IList<ThemeViewModel>> ListThemes()
         {