Add cache admin stats and move some shit internally

ReplayBrowser/Helpers/MemoryCacheExtensions.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using System.Reflection.Emit;
+using Microsoft.Extensions.Caching.Memory;
+
+namespace ReplayBrowser.Helpers;
+
+public static class MemoryCacheExtensions
+{
+#region Microsoft.Extensions.Caching.Memory_6_OR_OLDER
+
+    private static readonly Lazy<Func<MemoryCache, object>> GetEntries6 =
+        new Lazy<Func<MemoryCache, object>>(() => (Func<MemoryCache, object>)Delegate.CreateDelegate(
+            typeof(Func<MemoryCache, object>),
+            typeof(MemoryCache).GetProperty("EntriesCollection", BindingFlags.NonPublic | BindingFlags.Instance).GetGetMethod(true),
+            throwOnBindFailure: true));
+
+#endregion
+
+#region Microsoft.Extensions.Caching.Memory_7_OR_NEWER
+
+    private static readonly Lazy<Func<MemoryCache, object>> GetCoherentState =
+        new Lazy<Func<MemoryCache, object>>(() =>
+            CreateGetter<MemoryCache, object>(typeof(MemoryCache)
+                .GetField("_coherentState", BindingFlags.NonPublic | BindingFlags.Instance)));
+
+    private static readonly Lazy<Func<object, IDictionary>> GetEntries7 =
+        new Lazy<Func<object, IDictionary>>(() =>
+            CreateGetter<object, IDictionary>(typeof(MemoryCache)
+                .GetNestedType("CoherentState", BindingFlags.NonPublic)
+                .GetField("_entries", BindingFlags.NonPublic | BindingFlags.Instance)));
+
+    private static Func<TParam, TReturn> CreateGetter<TParam, TReturn>(FieldInfo field)
+    {
+        var methodName = $"{field.ReflectedType.FullName}.get_{field.Name}";
+        var method = new DynamicMethod(methodName, typeof(TReturn), new[] { typeof(TParam) }, typeof(TParam), true);
+        var ilGen = method.GetILGenerator();
+        ilGen.Emit(OpCodes.Ldarg_0);
+        ilGen.Emit(OpCodes.Ldfld, field);
+        ilGen.Emit(OpCodes.Ret);
+        return (Func<TParam, TReturn>)method.CreateDelegate(typeof(Func<TParam, TReturn>));
+    }
+
+#endregion
+
+    private static readonly Func<MemoryCache, IDictionary> GetEntries =
+        Assembly.GetAssembly(typeof(MemoryCache)).GetName().Version.Major < 7
+            ? (Func<MemoryCache, IDictionary>)(cache => (IDictionary)GetEntries6.Value(cache))
+            : cache => GetEntries7.Value(GetCoherentState.Value(cache));
+
+    public static ICollection GetKeys(this IMemoryCache memoryCache) =>
+        GetEntries((MemoryCache)memoryCache).Keys;
+
+    public static IEnumerable<T> GetKeys<T>(this IMemoryCache memoryCache) =>
+        memoryCache.GetKeys().OfType<T>();
+}

ReplayBrowser/Pages/Admin/AdminStats.razor

@@ -0,0 +1,87 @@
+@page "/account/admin/stats"
+@using System.Text.Json
+@using Microsoft.AspNetCore.Authorization
+@using Microsoft.AspNetCore.Components.Authorization
+@using Microsoft.Extensions.Caching.Memory
+@using ReplayBrowser.Helpers
+@using ReplayBrowser.Services
+@using Microsoft.AspNetCore.Components.Web
+@attribute [Authorize]
+@inject IMemoryCache MemoryCache
+@inject AuthenticationStateProvider AuthenticationStateProvider
+@inject AccountService AccountService
+@inject NavigationManager NavigationManager
+
+<link href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/themes/prism.min.css" rel="stylesheet" />
+<script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/prism.min.js"></script>
+<script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/components/prism-json.min.js"></script>
+
+<PageTitle>Cache Stats</PageTitle>
+
+<h3>AdminStats</h3>
+@if(!_authed)
+{
+    <div class="alert alert-danger" role="alert">
+        Not authorized
+    </div>
+}
+else
+{
+    var stats = MemoryCache.GetCurrentStatistics();
+    if (stats == null)
+    {
+        <div class="alert alert-info" role="alert">
+            No stats available
+        </div>
+    }
+    else
+    {
+        <div class="card">
+            <div class="card-body">
+                <p>Total hits: <span class="badge bg-primary">@stats.TotalHits</span></p>
+                <p>Total misses: <span class="badge bg-danger">@stats.TotalMisses</span></p>
+                <p>Total entries: <span class="badge bg-info">@stats.CurrentEntryCount</span></p>
+                <p>Estimated size: <span class="badge bg-warning">@stats.CurrentEstimatedSize</span></p>
+            </div>
+        </div>
+    }
+
+    var keys = MemoryCache.GetKeys();
+    foreach (var key in keys)
+    {
+        var entry = MemoryCache.Get(key);
+
+        <div class="card mt-3">
+            <div class="card-body">
+                <p>
+                    Key: <span class="text-muted">@key</span><br/>
+                    Value:
+                    <pre><code class="language-json">@JsonSerializer.Serialize(entry, new JsonSerializerOptions() { WriteIndented = true })</code></pre><br/>
+                </p>
+            </div>
+        </div>
+    }
+
+    <script>
+        $(document).ready(function() {
+            Prism.highlightAll();
+        });
+    </script>
+}
+@code {
+    private bool _authed = false;
+
+    protected override async Task OnInitializedAsync()
+    {
+        var authState = await AuthenticationStateProvider.GetAuthenticationStateAsync();
+        var user = await AccountService.GetAccount(authState);
+
+        if (user == null || !user.IsAdmin)
+        {
+            NavigationManager.NavigateTo("/");
+            return;
+        }
+
+        _authed = true;
+    }    
+}

ReplayBrowser/Startup.cs

@@ -1,8 +1,10 @@
 using System.IdentityModel.Tokens.Jwt;
 using System.Net;
+using System.Reflection;
 using System.Text.Json.Serialization;
 using Microsoft.AspNetCore.HttpOverrides;
 using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.IdentityModel.Protocols.OpenIdConnect;
 using OpenTelemetry.Metrics;
 using ReplayBrowser.Data;
@@ -27,6 +29,11 @@ public Startup(IConfiguration configuration)
 
     public void ConfigureServices(IServiceCollection services)
     {
+        services.AddMemoryCache(opts =>
+        {
+            opts.TrackStatistics = true;
+        });
+
         services.AddControllersWithViews().AddJsonOptions(options =>
         {
             options.JsonSerializerOptions.ReferenceHandler = ReferenceHandler.IgnoreCycles;
@@ -95,8 +102,6 @@ public void ConfigureServices(IServiceCollection services)
             });
         });
 
-        services.AddMemoryCache();
-
         // Endpoint logging
         services.Configure<RequestLoggingOptions>(options =>
         {