V2AS问路
ABP - 缓存模块(2)
阅读原文时间：2023年08月09日阅读：8

1. 缓存模块源码解析

个人觉得 ABP 分布式缓存模块有三个值得关注的核心点。首先是 AbpRedisCache 类继承了微软原生的 RedisCache，并 通过反射的方式获取RedisCache的私有方法对 RedisCache 进行扩展，实现了 ABP 分布式缓存中的批量操作方法。

为什么要这么做呢？因为基于 Redis 缓存的批量操作需要使用到 StackExchange.Redis 原生的SDK，而且在进行操作前总需要先进行 Redis 连接，而相应的方法和属性原生的 RedisCache 中都有，但是都是私有（private）的，在继承类中也无法使用，所以使用反射的方式提取出相应的方法和属性，以便在继承类中复用。这也是对于类功能进行继承扩展的时候的一种很有用的方式。

第二点是 ABP 缓存模块通过 IDistributedCache 接口扩展了原生的 IDistributedCache 接口的功能，而在具体实现上是将原有的 IDistributedCache 服务注入进行复用相应功能的，并在前后增加额外的逻辑对功能进行扩展增强，实际上就是适配器模式。

而最常使用的 IDistributedCache<CacheItem> 接口，以前其实现类是直接继承 DistributedCache 的，现在改成了直接用适配器模式。

最后一个是缓存的事务性，通过工作单元使缓存和其他事务操作保持原子性，避免缓存已经更新而其他事务失败回滚导致数据不一致的问题。实际上就是先不真正地更新缓存，而是将缓存数据通过字典保存在工作单元中，保证一个工作单元内拿到的缓存数据是最新的，同时注册工作单元提交事件，在工作单元正在提交成功的时候才执行真正更新缓存的逻辑。

工作单元相关的内容就后面再在专门的章节讲吧，这部分的内容比较复杂，一时半会比较难讲清。

2. 自己扩展的 IDistributedCache

ABP 框架扩展的 IDistributedCache 泛型接口在内部帮我们处理实例对象进行序列化/反序列化以及转码为 byte 数组的问题，大大提升了我们使用分布式缓存的方便性，但也存在一些问题。

  • 它是基于类的泛型，如果我们在一个服务中需要使用多个缓存类型的话，我们就得注入多个的泛型接口，还是有些不方便的

  • 它的缓存键是以默认是以泛型类型的全类名作为前缀，虽然我们可以通过特性指定类型名称，但是对于集合，缓存键就很不清晰了

    由于这些情况的存在，也基于我们在日常开发中的使用习惯，我在工作中又基于 ABP 的 IDistributedCache<CacheItem> 接口进行扩展。内部实现基本一致，主要就是将基于类的泛型，改成基于方法的泛型，并且提供自己的 IDistributedCacheKeyNormalizer 实现类，将缓存键的设置规则交给了缓存存取时进行设置。 代码如下：

    public interface IWantDistributedCache
    {
    ///

    /// Gets a cache item with the given key. If no cache item is found for the given key then returns null. ///
    /// The key of cached item to be retrieved from the cache.
    /// Indicates to throw or hide the exceptions for the distributed cache.
    /// This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.
    /// The cache item, or null.
    TCacheItem Get(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false
    ) where TCacheItem : class;

    /// <summary>
/// Gets multiple cache items with the given keys.
///
/// The returned list contains exactly the same count of items specified in the given keys.
/// An item in the return list can not be null, but an item in the list has null value
/// if the related key not found in the cache.
/// </summary>
/// <param name="keys">The keys of cached items to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <returns>List of cache items.</returns>
KeyValuePair<TCacheKey, TCacheItem>[] GetMany<TCacheItem, TCacheKey>(
    IEnumerable<TCacheKey> keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false
) where TCacheItem : class;

/// <summary>
/// Gets multiple cache items with the given keys.
///
/// The returned list contains exactly the same count of items specified in the given keys.
/// An item in the return list can not be null, but an item in the list has null value
/// if the related key not found in the cache.
///
/// </summary>
/// <param name="keys">The keys of cached items to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// /// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>List of cache items.</returns>
Task<KeyValuePair<TCacheKey, TCacheItem>[]> GetManyAsync<TCacheItem, TCacheKey>(
    IEnumerable<TCacheKey> keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

/// <summary>
/// Gets a cache item with the given key. If no cache item is found for the given key then returns null.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The cache item, or null.</returns>
Task<TCacheItem> GetAsync<TCacheItem, TCacheKey>(
    [NotNull] TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

/// <summary>
/// Gets or Adds a cache item with the given key. If no cache item is found for the given key then adds a cache item
/// provided by <paramref name="factory" /> delegate and returns the provided cache item.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="factory">The factory delegate is used to provide the cache item when no cache item is found for the given <paramref name="key" />.</param>
/// <param name="optionsFactory">The cache options for the factory delegate.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <returns>The cache item.</returns>
TCacheItem GetOrAdd<TCacheItem, TCacheKey>(
    TCacheKey key,
    Func<TCacheItem> factory,
    string cacheName,
    Func<DistributedCacheEntryOptions> optionsFactory = null,
    bool? hideErrors = null,
    bool considerUow = false
) where TCacheItem : class;

/// <summary>
/// Gets or Adds a cache item with the given key. If no cache item is found for the given key then adds a cache item
/// provided by <paramref name="factory" /> delegate and returns the provided cache item.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="factory">The factory delegate is used to provide the cache item when no cache item is found for the given <paramref name="key" />.</param>
/// <param name="optionsFactory">The cache options for the factory delegate.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The cache item.</returns>
Task<TCacheItem> GetOrAddAsync<TCacheItem, TCacheKey>(
    [NotNull] TCacheKey key,
    Func<Task<TCacheItem>> factory,
    string cacheName,
    Func<DistributedCacheEntryOptions> optionsFactory = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

/// <summary>
/// Sets the cache item value for the provided key.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="value">The cache item value to set in the cache.</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
void Set<TCacheItem, TCacheKey>(
    TCacheKey key,
    TCacheItem value,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false
) where TCacheItem : class;

/// <summary>
/// Sets the cache item value for the provided key.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="value">The cache item value to set in the cache.</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
Task SetAsync<TCacheItem, TCacheKey>(
    [NotNull] TCacheKey key,
    [NotNull] TCacheItem value,
    string cacheName,
    [CanBeNull] DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

/// <summary>
/// Sets multiple cache items.
/// Based on the implementation, this can be more efficient than setting multiple items individually.
/// </summary>
/// <param name="items">Items to set on the cache</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
void SetMany<TCacheItem, TCacheKey>(
    IEnumerable<KeyValuePair<TCacheKey, TCacheItem>> items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false
) where TCacheItem : class;

/// <summary>
/// Sets multiple cache items.
/// Based on the implementation, this can be more efficient than setting multiple items individually.
/// </summary>
/// <param name="items">Items to set on the cache</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
Task SetManyAsync<TCacheItem, TCacheKey>(
    IEnumerable<KeyValuePair<TCacheKey, TCacheItem>> items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

/// <summary>
/// Refreshes the cache value of the given key, and resets its sliding expiration timeout.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
void Refresh<TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null
);

/// <summary>
/// Refreshes the cache value of the given key, and resets its sliding expiration timeout.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
Task RefreshAsync<TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    CancellationToken token = default
);

/// <summary>
/// Removes the cache item for given key from cache.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
void Remove<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false
) where TCacheItem : class;

/// <summary>
/// Removes the cache item for given key from cache.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
Task RemoveAsync<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default
) where TCacheItem : class;

    }

    public class WantDistributedCache : IWantDistributedCache
    {
    public const string UowCacheName = "WantDistributedCache";

    public ILogger<WantDistributedCache> Logger { get; set; }

protected string CacheName { get; set; }

protected bool IgnoreMultiTenancy { get; set; }

protected IDistributedCache Cache { get; }

protected ICancellationTokenProvider CancellationTokenProvider { get; }

protected IDistributedCacheSerializer Serializer { get; }

protected IDistributedCacheKeyNormalizer KeyNormalizer { get; }

protected IHybridServiceScopeFactory ServiceScopeFactory { get; }

protected IUnitOfWorkManager UnitOfWorkManager { get; }

protected SemaphoreSlim SyncSemaphore { get; }

protected DistributedCacheEntryOptions DefaultCacheOptions;

private readonly AbpDistributedCacheOptions _distributedCacheOption;

public WantDistributedCache(
    IOptions<AbpDistributedCacheOptions> distributedCacheOption,
    IDistributedCache cache,
    ICancellationTokenProvider cancellationTokenProvider,
    IDistributedCacheSerializer serializer,
    IDistributedCacheKeyNormalizer keyNormalizer,
    IHybridServiceScopeFactory serviceScopeFactory,
    IUnitOfWorkManager unitOfWorkManager)
{
    _distributedCacheOption = distributedCacheOption.Value;
    Cache = cache;
    CancellationTokenProvider = cancellationTokenProvider;
    Logger = NullLogger<WantDistributedCache>.Instance;
    Serializer = serializer;
    KeyNormalizer = keyNormalizer;
    ServiceScopeFactory = serviceScopeFactory;
    UnitOfWorkManager = unitOfWorkManager;
    SyncSemaphore = new SemaphoreSlim(1, 1);

SetDefaultOptions();
    }

protected virtual string NormalizeKey<TCacheKey>(TCacheKey key, string cacheName)
{
    return KeyNormalizer.NormalizeKey(
        new DistributedCacheKeyNormalizeArgs(
            key.ToString(),
            cacheName,
            IgnoreMultiTenancy
        )
    );
}

protected virtual DistributedCacheEntryOptions GetDefaultCacheEntryOptions()
{
    foreach (var configure in _distributedCacheOption.CacheConfigurators)
    {
        var options = configure.Invoke(CacheName);
        if (options != null)
        {
            return options;
        }
    }
    return _distributedCacheOption.GlobalCacheEntryOptions;
    }

protected virtual void SetDefaultOptions()
{
    //CacheName = CacheNameAttribute.GetCacheName(typeof(TCacheItem));
    ////IgnoreMultiTenancy
//IgnoreMultiTenancy = typeof(TCacheItem).IsDefined(typeof(IgnoreMultiTenancyAttribute), true);

//Configure default cache entry options
DefaultCacheOptions = GetDefaultCacheEntryOptions();
    }

/// <summary>
/// Gets a cache item with the given key. If no cache item is found for the given key then returns null.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <returns>The cache item, or null.</returns>
public virtual TCacheItem Get<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    if (ShouldConsiderUow(considerUow))
{
    var value = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;().GetOrDefault(key)?.GetUnRemovedValueOrNull();
    if (value != null)
    {
        return value;
    }
}

byte[] cachedBytes;

try
{
    cachedBytes = Cache.Get(NormalizeKey(key, cacheName));
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        HandleException(ex);
        return null;
    }

    throw;
}

return ToCacheItem&lt;TCacheItem&gt;(cachedBytes);
    }

public virtual KeyValuePair<TCacheKey, TCacheItem>[] GetMany<TCacheItem, TCacheKey>(
    IEnumerable<TCacheKey> keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    var keyArray = keys.ToArray();
    var cacheSupportsMultipleItems = Cache as ICacheSupportsMultipleItems;
if (cacheSupportsMultipleItems == null)
{
    return GetManyFallback&lt;TCacheItem, TCacheKey&gt;(
        keyArray,
        cacheName,
        hideErrors,
        considerUow
    );
}

var notCachedKeys = new List&lt;TCacheKey&gt;();
var cachedValues = new List&lt;KeyValuePair&lt;TCacheKey, TCacheItem&gt;&gt;();
if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    foreach (var key in keyArray)
    {
        var value = uowCache.GetOrDefault(key)?.GetUnRemovedValueOrNull();
        if (value != null)
        {
            cachedValues.Add(new KeyValuePair&lt;TCacheKey, TCacheItem&gt;(key, value));
        }
    }

    notCachedKeys = keyArray.Except(cachedValues.Select(x =&gt; x.Key)).ToList();
    if (!notCachedKeys.Any())
    {
        return cachedValues.ToArray();
    }
}

hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
byte[][] cachedBytes;

var readKeys = notCachedKeys.Any() ? notCachedKeys.ToArray() : keyArray;
try
{
    cachedBytes = cacheSupportsMultipleItems.GetMany(readKeys.Select(key =&gt; NormalizeKey(key, cacheName)));
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        HandleException(ex);
        return ToCacheItemsWithDefaultValues&lt;TCacheItem, TCacheKey&gt;(keyArray);
    }

    throw;
}

return cachedValues.Concat(ToCacheItems&lt;TCacheItem, TCacheKey&gt;(cachedBytes, readKeys)).ToArray();
    }

protected virtual KeyValuePair<TCacheKey, TCacheItem>[] GetManyFallback<TCacheItem, TCacheKey>(
    TCacheKey[] keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    return keys
        .Select(key =&gt; new KeyValuePair&lt;TCacheKey, TCacheItem&gt;(
                key,
                Get&lt;TCacheItem, TCacheKey&gt;(key, cacheName, false, considerUow)
            )
        ).ToArray();
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        HandleException(ex);
        return ToCacheItemsWithDefaultValues&lt;TCacheItem, TCacheKey&gt;(keys);
    }

    throw;
}
    }

public virtual async Task<KeyValuePair<TCacheKey, TCacheItem>[]> GetManyAsync<TCacheItem, TCacheKey>(
    IEnumerable<TCacheKey> keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    var keyArray = keys.ToArray();
    var cacheSupportsMultipleItems = Cache as ICacheSupportsMultipleItems;
if (cacheSupportsMultipleItems == null)
{
    return await GetManyFallbackAsync&lt;TCacheItem, TCacheKey&gt;(
        keyArray,
        cacheName,
        hideErrors,
        considerUow,
        token
    );
}

var notCachedKeys = new List&lt;TCacheKey&gt;();
var cachedValues = new List&lt;KeyValuePair&lt;TCacheKey, TCacheItem&gt;&gt;();
if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    foreach (var key in keyArray)
    {
        var value = uowCache.GetOrDefault(key)?.GetUnRemovedValueOrNull();
        if (value != null)
        {
            cachedValues.Add(new KeyValuePair&lt;TCacheKey, TCacheItem&gt;(key, value));
        }
    }

    notCachedKeys = keyArray.Except(cachedValues.Select(x =&gt; x.Key)).ToList();
    if (!notCachedKeys.Any())
    {
        return cachedValues.ToArray();
    }
}

hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
byte[][] cachedBytes;

var readKeys = notCachedKeys.Any() ? notCachedKeys.ToArray() : keyArray;

try
{
    cachedBytes = await cacheSupportsMultipleItems.GetManyAsync(
        readKeys.Select(key =&gt; NormalizeKey(key, cacheName)),
        CancellationTokenProvider.FallbackToProvider(token)
    );
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        await HandleExceptionAsync(ex);
        return ToCacheItemsWithDefaultValues&lt;TCacheItem, TCacheKey&gt;(keyArray);
    }

    throw;
}

return cachedValues.Concat(ToCacheItems&lt;TCacheItem, TCacheKey&gt;(cachedBytes, readKeys)).ToArray();
    }

protected virtual async Task<KeyValuePair<TCacheKey, TCacheItem>[]> GetManyFallbackAsync<TCacheItem, TCacheKey>(
    TCacheKey[] keys,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    var result = new List&lt;KeyValuePair&lt;TCacheKey, TCacheItem&gt;&gt;();

    foreach (var key in keys)
    {
        result.Add(new KeyValuePair&lt;TCacheKey, TCacheItem&gt;(
            key,
            await GetAsync&lt;TCacheItem, TCacheKey&gt;(key, cacheName, false, considerUow, token: token))
        );
    }

    return result.ToArray();
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        await HandleExceptionAsync(ex);
        return ToCacheItemsWithDefaultValues&lt;TCacheItem, TCacheKey&gt;(keys);
    }

    throw;
}
    }

/// <summary>
/// Gets a cache item with the given key. If no cache item is found for the given key then returns null.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The cache item, or null.</returns>
public virtual async Task<TCacheItem> GetAsync<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    if (ShouldConsiderUow(considerUow))
{
    var value = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;().GetOrDefault(key)?.GetUnRemovedValueOrNull();
    if (value != null)
    {
        return value;
    }
}

byte[] cachedBytes;

try
{
    cachedBytes = await Cache.GetAsync(
        NormalizeKey(key, cacheName),
        CancellationTokenProvider.FallbackToProvider(token)
    );
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        await HandleExceptionAsync(ex);
        return null;
    }

    throw;
}

if (cachedBytes == null)
{
    return null;
}

return Serializer.Deserialize&lt;TCacheItem&gt;(cachedBytes);
    }

/// <summary>
/// Gets or Adds a cache item with the given key. If no cache item is found for the given key then adds a cache item
/// provided by <paramref name="factory" /> delegate and returns the provided cache item.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="factory">The factory delegate is used to provide the cache item when no cache item is found for the given <paramref name="key" />.</param>
/// <param name="optionsFactory">The cache options for the factory delegate.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <returns>The cache item.</returns>
public virtual TCacheItem GetOrAdd<TCacheItem, TCacheKey>(
    TCacheKey key,
    Func<TCacheItem> factory,
    string cacheName,
    Func<DistributedCacheEntryOptions> optionsFactory = null,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    var value = Get<TCacheItem, TCacheKey>(key, cacheName, hideErrors, considerUow);
    if (value != null)
    {
        return value;
    }
    using (SyncSemaphore.Lock())
{
    value = Get&lt;TCacheItem, TCacheKey&gt;(key, cacheName, hideErrors, considerUow);
    if (value != null)
    {
        return value;
    }

    value = factory();

    if (ShouldConsiderUow(considerUow))
    {
        var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
        if (uowCache.TryGetValue(key, out var item))
        {
            item.SetValue(value);
        }
        else
        {
            uowCache.Add(key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(value));
        }
    }

    Set(key, value, cacheName, optionsFactory?.Invoke(), hideErrors, considerUow);
}

return value;
    }

/// <summary>
/// Gets or Adds a cache item with the given key. If no cache item is found for the given key then adds a cache item
/// provided by <paramref name="factory" /> delegate and returns the provided cache item.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="factory">The factory delegate is used to provide the cache item when no cache item is found for the given <paramref name="key" />.</param>
/// <param name="optionsFactory">The cache options for the factory delegate.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The cache item.</returns>
public virtual async Task<TCacheItem> GetOrAddAsync<TCacheItem, TCacheKey>(
    TCacheKey key,
    Func<Task<TCacheItem>> factory,
    string cacheName,
    Func<DistributedCacheEntryOptions> optionsFactory = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    token = CancellationTokenProvider.FallbackToProvider(token);
    var value = await GetAsync<TCacheItem, TCacheKey>(key, cacheName, hideErrors, considerUow, token);
    if (value != null)
    {
        return value;
    }
    using (await SyncSemaphore.LockAsync(token))
{
    value = await GetAsync&lt;TCacheItem, TCacheKey&gt;(key, cacheName, hideErrors, considerUow, token);
    if (value != null)
    {
        return value;
    }

    value = await factory();

    if (ShouldConsiderUow(considerUow))
    {
        var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
        if (uowCache.TryGetValue(key, out var item))
        {
            item.SetValue(value);
        }
        else
        {
            uowCache.Add(key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(value));
        }
    }

    await SetAsync(key, value, cacheName, optionsFactory?.Invoke(), hideErrors, considerUow, token);
}

return value;
    }

/// <summary>
/// Sets the cache item value for the provided key.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="value">The cache item value to set in the cache.</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
public virtual void Set<TCacheItem, TCacheKey>(
    TCacheKey key,
    TCacheItem value,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    void SetRealCache()
    {
        hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
        try
    {
        Cache.Set(
            NormalizeKey(key, cacheName),
            Serializer.Serialize(value),
            options ?? DefaultCacheOptions
        );
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            HandleException(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    if (uowCache.TryGetValue(key, out _))
    {
        uowCache[key].SetValue(value);
    }
    else
    {
        uowCache.Add(key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(value));
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(() =&gt;
    {
        SetRealCache();
        return Task.CompletedTask;
    });
}
else
{
    SetRealCache();
}
    }
/// <summary>
/// Sets the cache item value for the provided key.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="value">The cache item value to set in the cache.</param>
/// <param name="options">The cache options for the value.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
public virtual async Task SetAsync<TCacheItem, TCacheKey>(
    TCacheKey key,
    TCacheItem value,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    async Task SetRealCache()
    {
        hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
        try
    {
        await Cache.SetAsync(
            NormalizeKey(key, cacheName),
            Serializer.Serialize(value),
            options ?? DefaultCacheOptions,
            CancellationTokenProvider.FallbackToProvider(token)
        );
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            await HandleExceptionAsync(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    if (uowCache.TryGetValue(key, out _))
    {
        uowCache[key].SetValue(value);
    }
    else
    {
        uowCache.Add(key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(value));
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(SetRealCache);
}
else
{
    await SetRealCache();
}
    }

public void SetMany<TCacheItem, TCacheKey>(
    IEnumerable<KeyValuePair<TCacheKey, TCacheItem>> items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    var itemsArray = items.ToArray();
    var cacheSupportsMultipleItems = Cache as ICacheSupportsMultipleItems;
if (cacheSupportsMultipleItems == null)
{
    SetManyFallback(
        itemsArray,
        cacheName,
        options,
        hideErrors,
        considerUow
    );

    return;
}

void SetRealCache()
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;

    try
    {
        cacheSupportsMultipleItems.SetMany(
            ToRawCacheItems(itemsArray, cacheName),
            options ?? DefaultCacheOptions
        );
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            HandleException(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();

    foreach (var pair in itemsArray)
    {
        if (uowCache.TryGetValue(pair.Key, out _))
        {
            uowCache[pair.Key].SetValue(pair.Value);
        }
        else
        {
            uowCache.Add(pair.Key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(pair.Value));
        }
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(() =&gt;
    {
        SetRealCache();
        return Task.CompletedTask;
    });
}
else
{
    SetRealCache();
}
    }

protected virtual void SetManyFallback<TCacheItem, TCacheKey>(
    KeyValuePair<TCacheKey, TCacheItem>[] items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    foreach (var item in items)
    {
        Set(
            item.Key,
            item.Value,
            cacheName,
            options,
            false,
            considerUow
        );
    }
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        HandleException(ex);
        return;
    }

    throw;
}
    }

public virtual async Task SetManyAsync<TCacheItem, TCacheKey>(
    IEnumerable<KeyValuePair<TCacheKey, TCacheItem>> items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    var itemsArray = items.ToArray();
    var cacheSupportsMultipleItems = Cache as ICacheSupportsMultipleItems;
if (cacheSupportsMultipleItems == null)
{
    await SetManyFallbackAsync(
        itemsArray,
        cacheName,
        options,
        hideErrors,
        considerUow,
        token
    );

    return;
}

async Task SetRealCache()
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;

    try
    {
        await cacheSupportsMultipleItems.SetManyAsync(
            ToRawCacheItems(itemsArray, cacheName),
            options ?? DefaultCacheOptions,
            CancellationTokenProvider.FallbackToProvider(token)
        );
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            await HandleExceptionAsync(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();

    foreach (var pair in itemsArray)
    {
        if (uowCache.TryGetValue(pair.Key, out _))
        {
            uowCache[pair.Key].SetValue(pair.Value);
        }
        else
        {
            uowCache.Add(pair.Key, new UnitOfWorkCacheItem&lt;TCacheItem&gt;(pair.Value));
        }
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(SetRealCache);
}
else
{
    await SetRealCache();
}
    }

protected virtual async Task SetManyFallbackAsync<TCacheItem, TCacheKey>(
    KeyValuePair<TCacheKey, TCacheItem>[] items,
    string cacheName,
    DistributedCacheEntryOptions options = null,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    foreach (var item in items)
    {
        await SetAsync(
            item.Key,
            item.Value,
            cacheName,
            options,
            false,
            considerUow,
            token: token
        );
    }
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        await HandleExceptionAsync(ex);
        return;
    }

    throw;
}
    }

/// <summary>
/// Refreshes the cache value of the given key, and resets its sliding expiration timeout.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
public virtual void Refresh<TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null)
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    Cache.Refresh(NormalizeKey(key, cacheName));
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        HandleException(ex);
        return;
    }

    throw;
}
    }

/// <summary>
/// Refreshes the cache value of the given key, and resets its sliding expiration timeout.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
public virtual async Task RefreshAsync<TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    CancellationToken token = default)
{
    hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
    try
{
    await Cache.RefreshAsync(NormalizeKey(key, cacheName), CancellationTokenProvider.FallbackToProvider(token));
}
catch (Exception ex)
{
    if (hideErrors == true)
    {
        await HandleExceptionAsync(ex);
        return;
    }

    throw;
}
    }

/// <summary>
/// Removes the cache item for given key from cache.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
public virtual void Remove<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false) where TCacheItem : class
{
    void RemoveRealCache()
    {
        hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
        try
    {
        Cache.Remove(NormalizeKey(key, cacheName));
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            HandleException(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    if (uowCache.TryGetValue(key, out _))
    {
        uowCache[key].RemoveValue();
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(() =&gt;
    {
        RemoveRealCache();
        return Task.CompletedTask;
    });
}
else
{
    RemoveRealCache();
}
    }

/// <summary>
/// Removes the cache item for given key from cache.
/// </summary>
/// <param name="key">The key of cached item to be retrieved from the cache.</param>
/// <param name="hideErrors">Indicates to throw or hide the exceptions for the distributed cache.</param>
/// <param name="considerUow">This will store the cache in the current unit of work until the end of the current unit of work does not really affect the cache.</param>
/// <param name="token">The <see cref="T:System.Threading.CancellationToken" /> for the task.</param>
/// <returns>The <see cref="T:System.Threading.Tasks.Task" /> indicating that the operation is asynchronous.</returns>
public virtual async Task RemoveAsync<TCacheItem, TCacheKey>(
    TCacheKey key,
    string cacheName,
    bool? hideErrors = null,
    bool considerUow = false,
    CancellationToken token = default) where TCacheItem : class
{
    async Task RemoveRealCache()
    {
        hideErrors = hideErrors ?? _distributedCacheOption.HideErrors;
        try
    {
        await Cache.RemoveAsync(NormalizeKey(key, cacheName), CancellationTokenProvider.FallbackToProvider(token));
    }
    catch (Exception ex)
    {
        if (hideErrors == true)
        {
            await HandleExceptionAsync(ex);
            return;
        }

        throw;
    }
}

if (ShouldConsiderUow(considerUow))
{
    var uowCache = GetUnitOfWorkCache&lt;TCacheItem, TCacheKey&gt;();
    if (uowCache.TryGetValue(key, out _))
    {
        uowCache[key].RemoveValue();
    }

    // ReSharper disable once PossibleNullReferenceException
    UnitOfWorkManager.Current.OnCompleted(RemoveRealCache);
}
else
{
    await RemoveRealCache();
}
    }

protected virtual void HandleException(Exception ex)
{
    AsyncHelper.RunSync(() => HandleExceptionAsync(ex));
}

protected virtual async Task HandleExceptionAsync(Exception ex)
{
    Logger.LogException(ex, LogLevel.Warning);
    using (var scope = ServiceScopeFactory.CreateScope())
{
    await scope.ServiceProvider
        .GetRequiredService&lt;IExceptionNotifier&gt;()
        .NotifyAsync(new ExceptionNotificationContext(ex, LogLevel.Warning));
}
    }

protected virtual KeyValuePair<TCacheKey, TCacheItem>[] ToCacheItems<TCacheItem, TCacheKey>(byte[][] itemBytes, TCacheKey[] itemKeys) where TCacheItem: class
{
    if (itemBytes.Length != itemKeys.Length)
    {
        throw new AbpException("count of the item bytes should be same with the count of the given keys");
    }
    var result = new List&lt;KeyValuePair&lt;TCacheKey, TCacheItem&gt;&gt;();

for (int i = 0; i &lt; itemKeys.Length; i++)
{
    result.Add(
        new KeyValuePair&lt;TCacheKey, TCacheItem&gt;(
            itemKeys[i],
            ToCacheItem&lt;TCacheItem&gt;(itemBytes[i])
        )
    );
}

return result.ToArray();
    }

[CanBeNull]
protected virtual TCacheItem ToCacheItem<TCacheItem>([CanBeNull] byte[] bytes) where TCacheItem : class
{
    if (bytes == null)
    {
        return null;
    }
    return Serializer.Deserialize&lt;TCacheItem&gt;(bytes);
    }

protected virtual KeyValuePair<string, byte[]>[] ToRawCacheItems<TCacheItem, TCacheKey>(KeyValuePair<TCacheKey, TCacheItem>[] items, string cacheName)
{
    return items
        .Select(i => new KeyValuePair<string, byte[]>(
                NormalizeKey(i.Key, cacheName),
                Serializer.Serialize(i.Value)
            )
        ).ToArray();
}

private static KeyValuePair<TCacheKey, TCacheItem>[] ToCacheItemsWithDefaultValues<TCacheItem, TCacheKey>(TCacheKey[] keys)
{
    return keys
        .Select(key => new KeyValuePair<TCacheKey, TCacheItem>(key, default))
        .ToArray();
}

protected virtual bool ShouldConsiderUow(bool considerUow)
{
    return considerUow && UnitOfWorkManager.Current != null;
}

protected virtual string GetUnitOfWorkCacheKey()
{
    return UowCacheName + CacheName;
}

protected virtual Dictionary<TCacheKey, UnitOfWorkCacheItem<TCacheItem>> GetUnitOfWorkCache<TCacheItem, TCacheKey>() where TCacheItem : class
{
    if (UnitOfWorkManager.Current == null)
    {
        throw new AbpException($"There is no active UOW.");
    }
    return UnitOfWorkManager.Current.GetOrAddItem(GetUnitOfWorkCacheKey(),
    key =&gt; new Dictionary&lt;TCacheKey, UnitOfWorkCacheItem&lt;TCacheItem&gt;&gt;());
    }

    }

    [Dependency(ReplaceServices = true)]
    public class WantDistributedCacheKeyNormalizer : IDistributedCacheKeyNormalizer, ITransientDependency
    {
    protected AbpDistributedCacheOptions DistributedCacheOptions { get; }

    public SuncereDistributedCacheKeyNormalizer(
    IOptions<AbpDistributedCacheOptions> distributedCacheOptions)
{
    DistributedCacheOptions = distributedCacheOptions.Value;
}

public virtual string NormalizeKey(DistributedCacheKeyNormalizeArgs args)
{
    // 缓存格式: a:appname,c:cachename,k:key
    var normalizedKey = $"a:{DistributedCacheOptions.KeyPrefix},c:{args.CacheName},k:{args.Key}";
    return normalizedKey;
}

    }

    [DependsOn(typeof(AbpCachingModule))]
    public class WantAbpCacheModule : AbpModule
    {
    public override void ConfigureServices(ServiceConfigurationContext context)
    {
    //注入缓存类
    context.Services.AddSingleton(typeof(ISuncereDistributedCache), typeof(SuncereDistributedCache));
    }
    }

参考文章：

ABP 官方文档 - 缓存

ABP 系列总结：

目录：ABP 系列总结

上一篇：ABP - 缓存模块(1)

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