/// <summary>
/// QueryCache级别存储
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="cacheValue"></param>
internal void CacheData <T>(T cacheValue)
{
string sqlQueryCacheKey = GetSqlQueryCacheKey();
string queryCacheKey = GetQueryCacheKey();
//如果缓存中存在，则拿到表单位的缓存并更新
//这里用object类型进行存储，因为字典的value可能有list集合，int，object等多种类型，泛型使用会出现识别异常
if (CacheStorageManager.IsExist(queryCacheKey, out Dictionary <string, object> t))
{
//如果超出单表的query缓存键阈值，则按先后顺序进行移除
if (t.Count >= CacheOptions.QueryCacheMaxCountPerTable)
{
t.Remove(t.First().Key);
}
t.AddOrUpdate(sqlQueryCacheKey, cacheValue);
CacheStorageManager.Put(queryCacheKey, t, CacheOptions.QueryCacheExpiredTimeSpan);
}
//如果缓存中没有表单位的缓存，则直接新增表单位的sql键缓存
else
{
var dic = new Dictionary <string, object> {
{ sqlQueryCacheKey, cacheValue }
};
CacheStorageManager.Put(queryCacheKey, dic, CacheOptions.QueryCacheExpiredTimeSpan);
}
}
/// <summary>
/// 清空所有缓存
/// </summary>
public void FlushAllCache()
{
if (CacheStorageManager.IsExist(CachingConst.GetQueryCacheKeysCacheKey(DbContext.DataBaseName), out HashSet <string> keys))
{
foreach (var item in keys)
{
CacheStorageManager.Delete(item);
}
}
}
/// <summary>
/// 从缓存中获取数据
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="DbContext"></param>
/// <returns></returns>
internal T GetEntitiesFromCache <T>()
{
//如果QueryCache里面有该缓存键，则直接获取，并从单个表单位中获取到对应sql的值
if (CacheStorageManager.IsExist(GetQueryCacheKey(), out Dictionary <string, object> t))
{
string sqlQueryCacheKey = GetSqlQueryCacheKey();
if (t.ContainsKey(sqlQueryCacheKey))
{
DbContext.IsFromCache = true;
return(TypeConvertHelper.ToGenericType <T>(t[sqlQueryCacheKey]));
}
}
return(default(T));
}
/// <summary>
/// 更新数据到缓存（Add）
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext"></param>
/// <param name="entity"></param>
internal void AddCache <TEntity>(TEntity entity)
{
var tableName = TableAttribute.GetName(typeof(TEntity));
//如果存在表级别缓存，则更新数据到缓存
if (CacheStorageManager.IsExist(GetTableCacheKey(tableName), out List <TEntity> entities))
{
if (TableCachingAttribute.IsExistTaleCaching(typeof(TEntity), out TimeSpan tableCacheTimeSpan))
{
entities.Add(entity);
//如果过期时间为0，则取上下文的过期时间
CacheStorageManager.Put(GetTableCacheKey(tableName), entities, tableCacheTimeSpan == TimeSpan.Zero ? CacheOptions.TableCacheExpiredTimeSpan : tableCacheTimeSpan);
}
}
}
/// <summary>
/// 构建sql查询缓存的总key
/// </summary>
/// <returns></returns>
private string GetQueryCacheKey(string collectionName = null)
{
string key = $"{CachingConst.CacheKey_QueryCache}{collectionName ?? DbContext.CollectionName}";
//缓存键更新
if (!CacheStorageManager.IsExist(CachingConst.GetQueryCacheKeysCacheKey(DbContext.DataBaseName), out HashSet <string> keys))
{
keys = new HashSet <string>();
}
keys.Add(key);
CacheStorageManager.Put(CachingConst.GetQueryCacheKeysCacheKey(DbContext.DataBaseName), keys, CacheOptions.MaxExpiredTimeSpan);
return(key);
}
/// <summary>
/// 从缓存中获取数据，如果没有，则后台执行扫描表任务
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext"></param>
/// <param name="filter"></param>
/// <returns></returns>
internal List <TEntity> GetEntitiesFromCache <TEntity>(Expression <Func <TEntity, bool> > filter) where TEntity : class
{
Ensure.ArgumentNotNullOrEmpty(filter, nameof(filter));
//1.如果TableCache里面有该缓存键，则直接获取
if (CacheStorageManager.IsExist(GetTableCacheKey(TableAttribute.GetName(typeof(TEntity))), out List <TEntity> entities))
{
DbContext.IsFromCache = true;
return(entities.Where(filter.Compile()).ToList());
}
//2.则判断是否需要对该表进行扫描（含有TableCachingAttribute的标记的类才可以有扫描全表的权限）
if (TableCachingAttribute.IsExistTaleCaching(typeof(TEntity), out TimeSpan tableCacheTimeSpan))
{
//执行扫描全表数据任务
ScanTableBackground <TEntity>(tableCacheTimeSpan);
}
return(null);
}
/// <summary>
/// 更新数据到缓存（Delete）
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext"></param>
/// <param name="entity"></param>
internal void DeleteCache <TEntity>(TEntity entity)
{
var tableName = TableAttribute.GetName(typeof(TEntity));
//如果存在表级别缓存，则更新数据到缓存
if (CacheStorageManager.IsExist(GetTableCacheKey(tableName), out List <TEntity> entities))
{
if (TableCachingAttribute.IsExistTaleCaching(typeof(TEntity), out TimeSpan tableCacheTimeSpan))
{
//如果过期时间为0，则取上下文的过期时间
TimeSpan timeSpan = tableCacheTimeSpan == TimeSpan.Zero ? CacheOptions.TableCacheExpiredTimeSpan : tableCacheTimeSpan;
//从缓存集合中寻找该记录，如果找到，则更新该记录
var val = entities.Find(t => t.Equals(entity));
if (val != null)
{
entities.Remove(val);
CacheStorageManager.Put(GetTableCacheKey(tableName), entities, tableCacheTimeSpan);
}
}
}
}
/// <summary>
/// 后台扫描全表数据
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext">上下文</param>
/// <param name="tableCacheTimeSpan">tableCache过期时间</param>
private void ScanTableBackground <TEntity>(TimeSpan tableCacheTimeSpan) where TEntity : class
{
string scanKey = $"{CachingConst.CacheKey_TableScanning}{DbContext.CollectionName}";
//1.判断正在扫描键是否存在，如果存在，则返回null，继续等待扫描任务完成
if (CacheStorageManager.IsExist(scanKey))
{
return;
}
//设置扫描键，标识当前正在进行扫描
CacheStorageManager.Put(scanKey, 1, CachingConst.SpanScaningKeyExpiredTime);
//2.如果没有扫描键，则执行后台扫描任务
Task.Factory.StartNew(() =>
{
//对扫描任务加锁，防止多线程环境多次执行任务
lock (tableScaningLocker)
{
var tableName = TableAttribute.GetName(typeof(TEntity));
//双重校验当前缓存是否存在TableCache，防止重复获取
if (CacheStorageManager.IsExist(GetTableCacheKey(tableName)))
{
return;
}
//如果过期时间为0，则取上下文的过期时间
TimeSpan timeSpan = tableCacheTimeSpan == TimeSpan.Zero ? CacheOptions.TableCacheExpiredTimeSpan : tableCacheTimeSpan;
//执行扫描全表任务，并将结果存入缓存中
var data = DbContext.GetFullCollectionData <TEntity>();
//如果没查到，会存个空的集合
CacheStorageManager.Put(GetTableCacheKey(tableName), data ?? new List <TEntity>(), CacheOptions.TableCacheExpiredTimeSpan);
}
//将扫描键移除，表示已经扫描完成
CacheStorageManager.Delete(scanKey);
});
}
/// <summary>
/// 更新数据到缓存（Delete）
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext"></param>
/// <param name="filter"></param>
internal void DeleteCache <TEntity>(Expression <Func <TEntity, bool> > filter)
{
Ensure.ArgumentNotNullOrEmpty(filter, nameof(filter));
var tableName = TableAttribute.GetName(typeof(TEntity));
//如果存在表级别缓存，则更新数据到缓存
if (CacheStorageManager.IsExist(GetTableCacheKey(tableName), out List <TEntity> entities))
{
if (TableCachingAttribute.IsExistTaleCaching(typeof(TEntity), out TimeSpan tableCacheTimeSpan))
{
//从缓存集合中寻找该记录，如果找到，则更新该记录
var list = entities.Where(filter.Compile()).ToList();
if (list != null && list.Any())
{
entities.RemoveAll(t => list.Contains(t));
//如果过期时间为0，则取上下文的过期时间
CacheStorageManager.Put(GetTableCacheKey(tableName), entities, tableCacheTimeSpan == TimeSpan.Zero ? CacheOptions.TableCacheExpiredTimeSpan : tableCacheTimeSpan);
}
}
}
}
/// <summary>
/// 更新数据到缓存（Update）
/// </summary>
/// <typeparam name="TEntity"></typeparam>
/// <param name="dbContext"></param>
/// <param name="entity"></param>
/// <param name="filter"></param>
internal void UpdateCache <TEntity>(TEntity entity, Expression <Func <TEntity, bool> > filter)
{
Ensure.ArgumentNotNullOrEmpty(filter, nameof(filter));
var tableName = TableAttribute.GetName(typeof(TEntity));
//如果存在表级别缓存，则更新数据到缓存
if (CacheStorageManager.IsExist(GetTableCacheKey(tableName), out List <TEntity> entities))
{
if (TableCachingAttribute.IsExistTaleCaching(typeof(TEntity), out TimeSpan tableCacheTimeSpan))
{
//如果过期时间为0，则取上下文的过期时间
TimeSpan timeSpan = tableCacheTimeSpan == TimeSpan.Zero ? CacheOptions.TableCacheExpiredTimeSpan : tableCacheTimeSpan;
//从缓存集合中寻找该记录，如果找到，则更新该记录
var val = entities.Where(filter.Compile()).FirstOrDefault();
if (val != null)
{
val = entity;
CacheStorageManager.Put(GetTableCacheKey(tableName), entities, timeSpan);
}
}
}
}
protected CacheManagerBase(DbContext context, CacheOptions cacheOptions)
{
DbContext = context;
CacheOptions = cacheOptions;
CacheStorageManager = new CacheStorageManager(cacheOptions);
}
/// <summary>
/// 清空单个表相关的所有缓存
/// </summary>
/// <param name="dbContext"></param>
public void FlushCollectionCache(string collectionName = null)
{
CacheStorageManager.Delete(GetQueryCacheKey(collectionName));
}