/// <summary>
/// 异步的，尝试获取指定缓存键的对象，如果没有则使用函数添加对象到缓存中。
/// </summary>
/// <typeparam name="T">缓存对象的类型。</typeparam>
/// <param name="cacheKey">用于引用对象的缓存键。</param>
/// <param name="valueCreator">用于添加缓存对象的函数。</param>
/// <param name="expiration">判断对象过期的对象。</param>
/// <param name="cancellationToken">取消操作的通知。</param>
/// <returns></returns>
public async Task <T> TryGetAsync <T>(string cacheKey, Func <Task <T> > valueCreator, Func <ICacheItemExpiration> expiration = null, CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
cacheKey = ServiceProvider.GetCacheKey(cacheKey);
var client = GetConnection(cacheKey);
try
{
async Task <CheckCache <T> > GetCacheValue()
{
if (await client.ExistsAsync(cacheKey))
{
var redisValue = await client.GetAsync(cacheKey);
if (!string.IsNullOrEmpty(redisValue))
{
await HandleSlidingTimeAsync(client, cacheKey);
return(CheckCache <T> .Result(Deserialize <T>(redisValue)));
}
}
return(CheckCache <T> .Null());
}
var ck = await GetCacheValue();
if (ck.HasValue)
{
return(ck.Value);
}
return(await RedisHelper.LockAsync(client, GetLockToken(cacheKey), Setting.LockTimeout, async() =>
{
var ck1 = await GetCacheValue();
if (ck1.HasValue)
{
return ck1.Value;
}
var expiry = GetExpirationTime(expiration);
var value = await valueCreator();
await client.SetAsync(cacheKey, Serialize(value), expiry == null ? -1 : (int)expiry.Value.TotalSeconds);
return value;
}));
}
catch (IOException exp)
{
if (Setting.IgnoreException)
{
Tracer.Error($"RedisCache TryGetValue throw exception:\n{exp.Output()}");
return(await valueCreator());
}
throw exp;
}
}
/// <summary>
/// 尝试获取指定缓存键的对象，如果没有则使用函数添加对象到缓存中。
/// </summary>
/// <typeparam name="T">缓存对象的类型。</typeparam>
/// <param name="cacheKey">用于引用对象的缓存键。</param>
/// <param name="valueCreator">用于添加缓存对象的函数。</param>
/// <param name="expiration">判断对象过期的对象。</param>
/// <returns></returns>
public T TryGet <T>(string cacheKey, Func <T> valueCreator, Func <ICacheItemExpiration> expiration = null)
{
cacheKey = ServiceProvider.GetCacheKey(cacheKey);
var client = GetConnection(cacheKey);
try
{
CheckCache <T> GetCacheValue()
{
if (client.Exists(cacheKey))
{
var redisValue = client.Get(cacheKey);
if (!string.IsNullOrEmpty(redisValue))
{
HandleSlidingTime(client, cacheKey);
return(CheckCache <T> .Result(Deserialize <T>(redisValue)));
}
}
return(CheckCache <T> .Null());
}
var ck = GetCacheValue();
if (ck.HasValue)
{
return(ck.Value);
}
return(RedisHelper.Lock(client, GetLockToken(cacheKey), Setting.LockTimeout, () =>
{
var ck1 = GetCacheValue();
if (ck1.HasValue)
{
return ck1.Value;
}
var expiry = GetExpirationTime(expiration);
var value = valueCreator();
client.Set(cacheKey, base.Serialize(value), expiry == null ? -1 : (int)expiry.Value.TotalSeconds);
return value;
}));
}
catch (IOException exp)
{
if (Setting.IgnoreException)
{
Tracer.Error($"RedisCache TryGetValue throw exception:\n{exp.Output()}");
return(valueCreator());
}
throw exp;
}
}
/// <summary>
/// 异步的，尝试从集合中获取指定 <paramref name="key"/> 的数据，如果没有则使用函数添加对象到集合中。
/// </summary>
/// <param name="key">标识数据的 key。</param>
/// <param name="valueCreator">用于添加缓存对象的函数。</param>
/// <param name="expiration">判断对象过期的对象。</param>
/// <param name="cancellationToken">取消操作的通知。</param>
/// <returns></returns>
public async Task <TValue> TryGetAsync(TKey key, Func <Task <TValue> > valueCreator, Func <ICacheItemExpiration> expiration = null, CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
TryReInitialize();
var sKey = key.ToString();
async Task <CheckCache <TValue> > GetCacheValue()
{
if (await _client.HExistsAsync(_cacheKey, sKey))
{
var content = await _client.HGetAsync(_cacheKey, sKey);
var item = _deserialize(content);
if (!item.HasExpired())
{
return(CheckCache <TValue> .Result(item.Value));
}
}
return(CheckCache <TValue> .Null());
}
var ck = await GetCacheValue();
if (ck.HasValue)
{
return(ck.Value);
}
return(await RedisHelper.LockAsync(_client, string.Concat(_cacheKey, ":", sKey), _setting.LockTimeout, async() =>
{
var ck1 = await GetCacheValue();
if (ck1.HasValue)
{
return ck1.Value;
}
var value = await valueCreator();
var content = _serialize(new RedisCacheItem <TValue>(value, expiration == null ? NeverExpired.Instance : expiration()));
await _client.HSetAsync(_cacheKey, sKey, content);
return value;
}));
}
/// <summary>
/// 尝试从集合中获取指定 <paramref name="key"/> 的数据，如果没有则使用函数添加对象到集合中。
/// </summary>
/// <param name="key">标识数据的 key。</param>
/// <param name="valueCreator">用于添加缓存对象的函数。</param>
/// <param name="expiration">判断对象过期的对象。</param>
/// <returns></returns>
public TValue TryGet(TKey key, Func <TValue> valueCreator, Func <ICacheItemExpiration> expiration = null)
{
TryReInitialize();
var sKey = key.ToString();
CheckCache <TValue> GetCacheValue()
{
if (_client.HExists(_cacheKey, sKey))
{
var content = _client.HGet(_cacheKey, sKey);
var item = _deserialize(content);
if (!item.HasExpired())
{
return(CheckCache <TValue> .Result(item.Value));
}
}
return(CheckCache <TValue> .Null());
}
var ck = GetCacheValue();
if (ck.HasValue)
{
return(ck.Value);
}
return(RedisHelper.Lock(_client, string.Concat(_cacheKey, ":", sKey), _setting.LockTimeout, () =>
{
var ck1 = GetCacheValue();
if (ck1.HasValue)
{
return ck1.Value;
}
var value = valueCreator();
var content = _serialize(new RedisCacheItem <TValue>(value, expiration == null ? NeverExpired.Instance : expiration()));
_client.HSet(_cacheKey, sKey, content);
return value;
}));
}
