EFCoreSecondLevelCacheInterceptor Distributed cached provider using Redis sentinel

EFRedisCacheProvider.cs

using adenin.Platform.Configuration;
using EFCoreSecondLevelCacheInterceptor;
using JetBrains.Annotations;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Newtonsoft.Json;
using StackExchange.Redis;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;

namespace adenin.Platform.Caching;

// ReSharper disable once InconsistentNaming
public class EFRedisCacheProvider : IEFCacheServiceProvider
{
    public const string CacheName = "PlatformEFFusionCache";
    
    private readonly IServiceProvider _serviceProvider;
    private readonly ILogger<EFRedisCacheProvider> _redisCacheProviderLogger;

    private readonly ConcurrentDictionary<string, ConnectionMultiplexer> _redisConnections = new(StringComparer.Ordinal);
    
    public EFRedisCacheProvider(
        IOptions<EFCoreSecondLevelCacheSettings> cacheSettings,
        IServiceProvider serviceProvider,
        ILogger<EFRedisCacheProvider> redisCacheProviderLogger)
    {
        ArgumentNullException.ThrowIfNull(cacheSettings);
        ArgumentNullException.ThrowIfNull(serviceProvider);

        _serviceProvider = serviceProvider;
        _redisCacheProviderLogger = redisCacheProviderLogger;
    }

    public void InsertValue(EFCacheKey cacheKey, [CanBeNull] EFCachedData value, EFCachePolicy cachePolicy)
    {
        ArgumentNullException.ThrowIfNull(cacheKey);
        ArgumentNullException.ThrowIfNull(cachePolicy);

        value ??= new EFCachedData { IsNull = true };

        var redisDb = GetRedisConnection().GetDatabase();
        var keyHash = cacheKey.KeyHash;

        foreach (var rootCacheKey in cacheKey.CacheDependencies)
        {
            if (string.IsNullOrWhiteSpace(rootCacheKey))
            {
                continue;
            }

            var expiryTime = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds() + cachePolicy.CacheTimeout.TotalMilliseconds;

            redisDb.SortedSetAdd(SortedSetCacheKey(rootCacheKey), keyHash, expiryTime);
        }

        var data = Serialize(value);

        redisDb.StringSet(keyHash, data, cachePolicy.CacheTimeout);
    }

    public void ClearAllCachedEntries()
    {
        _redisCacheProviderLogger.LogWarning("EFFusionCacheProvider.ClearAllCachedEntries was called");
    }

    public EFCachedData? GetValue(EFCacheKey cacheKey, EFCachePolicy cachePolicy)
    {
        ArgumentNullException.ThrowIfNull(cacheKey);

        var redisDb = GetRedisConnection().GetDatabase();
        var maybeValue = redisDb.StringGet(cacheKey.KeyHash);

        return maybeValue.HasValue ? Deserialize<EFCachedData>(maybeValue) : null;
    }

    public void InvalidateCacheDependencies(EFCacheKey cacheKey)
    {
        ArgumentNullException.ThrowIfNull(cacheKey);

        var redisDb = GetRedisConnection().GetDatabase();

        foreach (var rootCacheKey in cacheKey.CacheDependencies)
        {
            if (string.IsNullOrWhiteSpace(rootCacheKey))
            {
                continue;
            }

            var setKey = SortedSetCacheKey(rootCacheKey);
            var dependencyKeys = new HashSet<string>();

            foreach (var item in redisDb.SortedSetScan(setKey))
            {
                _ = dependencyKeys.Add(item.Element);
            }

            if (dependencyKeys.Count > 0)
            {
                redisDb.KeyDelete([.. dependencyKeys]);
            }

            redisDb.KeyDelete(setKey);
        }
    }

    private ConnectionMultiplexer GetRedisConnection()
    {
        return _redisConnections.GetOrAdd("redis", _ =>
        {
            var config = _serviceProvider.GetRequiredService<IWebHostEnvironment>();
            var redisSetting = config.GetAppConfiguration().GetValue<string>("RedisConnectionString");
            var hosts = redisSetting.Split(',');

            if (hosts.Length <= 1)
            {
                return ConnectionMultiplexer.Connect(redisSetting);
            }

            var endpoints = new EndPointCollection();

            foreach (var host in hosts)
            {
                endpoints.Add(host, 26379);
            }

            var redisOptions = new ConfigurationOptions
            {
                EndPoints = endpoints,
                ServiceName = "mymaster",
                TieBreaker = ""
            };

            return ConnectionMultiplexer.Connect(redisOptions);
        });
    }

    private static string SortedSetCacheKey(string rootCacheKey) => $"{rootCacheKey}:Sets";

    private static string Serialize<T>(T? obj)
    {
        return JsonConvert.SerializeObject(obj);
    }

    private static T? Deserialize<T>(string data)
    {
        return JsonConvert.DeserializeObject<T>(data);
    }
}