private bool HasCachePut(CacheOperationContexts contexts)
{
// Evaluate the conditions *without* the result object because we don't have it yet...
ICollection <CacheOperationContext> cachePutContexts = contexts.Get(typeof(CachePutOperation));
ICollection <CacheOperationContext> excluded = new List <CacheOperationContext>();
foreach (var context in cachePutContexts)
{
try
{
if (!context.IsConditionPassing(CacheOperationExpressionEvaluator.NO_RESULT))
{
excluded.Add(context);
}
}
catch (Exception e)
{
}
}
// Check if all puts have been excluded by condition
return(cachePutContexts.Count != excluded.Count);
}
private object Execute(Func <object> invoker, MethodInfo method, CacheOperationContexts contexts)
{
//var context = contexts.Get(typeof(CacheableOperation)).FirstOrDefault();
//if (context!=null&&context.IsConditionPassing(CacheOperationExpressionEvaluator.NO_RESULT))
//{
// var key = context.GenerateKey(CacheOperationExpressionEvaluator.NO_RESULT);
// var cache = context.Caches.FirstOrDefault();
// if(cache==null) return new object();
// return cache.Get<object>(key.ToString(), null);
//}
//else
//{
// return invoker();
//}
//判断方法返回值是否为异步类型
var isAsyncReturnType = method.ReturnType.IsAsyncType();
//返回类型
var returnType = isAsyncReturnType ? method.ReturnType.GenericTypeArguments.First() : method.ReturnType;
//先清除符合条件的缓存
ProcessCacheEvicts(contexts.Get(typeof(CacheEvictOperation)), true,
CacheOperationExpressionEvaluator.NO_RESULT);
//从缓存中查找结果值
var cacheHit = FindCachedItem(contexts.Get(typeof(CacheableOperation)), returnType);
// Collect puts from any @Cacheable miss, if no cached item is found
var cachePutRequests = new List <CachePutRequest>();
//如果未命中，则收集这个查询
if (cacheHit == null)
{
CollectPutRequests(contexts.Get(typeof(CacheableOperation)),
CacheOperationExpressionEvaluator.NO_RESULT, cachePutRequests);
}
//缓存得结果值
var cacheValue = new object();
//如果命中，直接获得命中的结果值作为返回值
if (cacheHit != null && !HasCachePut(contexts))
{
// If there are no put requests, just use the cache hit
cacheValue = cacheHit.Get();
}
else
//如果未命中，则执行具体方法，获得返回值
{
var cacheValueInvoker = invoker();
if (isAsyncReturnType)
{
//如果是异步结果，则获取task里的result
var resultProperty = typeof(Task <>).MakeGenericType(returnType).GetProperty("Result");
cacheValue = resultProperty?.GetValue(cacheValueInvoker);
}
else
{
//同步则直接为结果
cacheValue = cacheValueInvoker;
}
}
// 收集所有put的请求
CollectPutRequests(contexts.Get(typeof(CachePutOperation)), cacheValue, cachePutRequests);
//执行所有收集到的put请求，无论是CachePut还是Cacheable未命中
foreach (var putRequest in cachePutRequests)
{
putRequest.Apply(cacheValue);
}
//执行清除请求
ProcessCacheEvicts(contexts.Get(typeof(CacheEvictOperation)), false,
cacheValue);
if (isAsyncReturnType)
{
//如果是异步方法，需要对结果值进行封装
var result = typeof(Task).GetMethods().First(p => p.Name == "FromResult" && p.ContainsGenericParameters)
.MakeGenericMethod(returnType).Invoke(null, new object[] { cacheValue });
return(result);
}
return(cacheValue);
}
