public static MemcachedQueueEnqueueResult Enqueue(string queueName, object data, int generation = 0, uint maxRetryTimes = 2)
{
if (maxRetryTimes < 0)
{
maxRetryTimes = 0;
}
if (string.IsNullOrWhiteSpace(queueName))
{
throw new ArgumentNullException("queueName");
}
queueName = queueName.Trim();
string localCacheKey = "MemQ.Id|" + queueName;
bool rst = false;
var client = MemcachedCacheHelper.GetClientInstance();
ulong? index;
string queueId;
bool notReadFromLocalCache = false;
do
{
queueId = GetOrCreateQueueId(queueName, notReadFromLocalCache);
index = client.Increment(BuildIndexKey(queueId, MemcachedQueueIndexType.Enqueue), 1);
if (index == null) // 有可能本地缓存读取的id已经过期试下了，需要在下次循环执行时，不走本地缓存重新获取
{
notReadFromLocalCache = true;
}
}while (index == null);
// 程序执行到这里，EnqueueIndex已经被增长上去了，但此index处的数据还未Set写入，那么此时并发的Dequeue操作则有可能读取到此index的，但获取数据是获取不到的
// 所以在Dequeue方法里有针对这种极端并发的处理代码，结合这里的代码注释就容易理解了
string itemKey = BuildItemIndexKey(queueId, index.Value);
var item = new MemcachedQueueItem {
Data = data, Generation = generation
};
rst = client.Set(itemKey, item); // 程序执行到这里才真正开始将此index的数据写入
int retryTime = 0;
while (rst == false) // 如果写入失败，则重试
{
if (retryTime >= maxRetryTimes) // 重试次数达到最大重试次数，则不再重试
{
break;
}
Thread.Sleep(10); // 等待10ms再试
rst = client.Set(itemKey, item);
retryTime++;
}
return(new MemcachedQueueEnqueueResult(queueName, rst, index.Value));
}
public static MemcachedQueueItem[] GetAllItems(string queueName)
{
if (string.IsNullOrWhiteSpace(queueName))
{
throw new ArgumentNullException("queueName");
}
queueName = queueName.Trim();
string queueId = GetQueueId(queueName);
if (string.IsNullOrWhiteSpace(queueId)) // 队列列表里未找到指定名称的队列
{
return(new MemcachedQueueItem[0]);
}
var ary = GetIndexById(queueId, MemcachedQueueIndexType.Dequeue, MemcachedQueueIndexType.Enqueue);
ulong de_index = ary == null || ary.Length <= 0 ? 0 : ary[0];
ulong en_index = ary == null || ary.Length <= 1 ? 0 : ary[1];
if (en_index <= de_index) // 说明队列是空的
{
return(new MemcachedQueueItem[0]);
}
ulong len = en_index - de_index;
MemcachedQueueItem[] rstList = new MemcachedQueueItem[len];
const ulong maxBatchSize = 100;
ulong itemIndex = de_index;
int index = 0;
var client = MemcachedCacheHelper.GetClientInstance();
while (itemIndex < en_index)
{
ulong leftItemCount = en_index - itemIndex;
uint batchSize = (uint)(leftItemCount < maxBatchSize ? leftItemCount : maxBatchSize);
string[] keys = new string[batchSize];
for (uint i = 0; i < batchSize; i++)
{
itemIndex++;
keys[i] = BuildItemIndexKey(queueId, itemIndex);
}
var objs = client.Get(keys);
for (uint i = 0; i < batchSize; i++)
{
var obj = (objs == null || i >= objs.Length) ? null : objs[i];
rstList[index] = obj as MemcachedQueueItem;
index++;
}
}
return(rstList);
}
public static MemcachedQueueItem GetItemWithProcessResult(string queueName, long index, out MemcachedQueueItemProcessResult processResult)
{
if (string.IsNullOrWhiteSpace(queueName))
{
throw new ArgumentNullException("queueName");
}
if (index <= 0)
{
processResult = null;
return(null);
}
queueName = queueName.Trim();
var queueId = GetQueueId(queueName);
if (string.IsNullOrWhiteSpace(queueId))
{
processResult = null;
return(null);
}
string itemKey = BuildItemIndexKey(queueId, (ulong)index);
string itemProcessdResultKey = BuildItemIndexKeyForProcessResult(queueId, (ulong)index);
var client = MemcachedCacheHelper.GetClientInstance();
var objs = client.Get(new string[] { itemKey, itemProcessdResultKey });
MemcachedQueueItem item = null;
processResult = null;
if (objs != null)
{
if (objs.Length > 0)
{
item = objs[0] as MemcachedQueueItem;
}
if (objs.Length > 1)
{
processResult = objs[1] as MemcachedQueueItemProcessResult;
}
}
return(item);
}
public static MemcachedQueueItem[] GetItem(string queueName, long[] indexs)
{
if (string.IsNullOrWhiteSpace(queueName))
{
throw new ArgumentNullException("queueName");
}
if (indexs == null || indexs.Length <= 0)
{
return(new MemcachedQueueItem[0]);
}
queueName = queueName.Trim();
var queueId = GetQueueId(queueName);
if (string.IsNullOrWhiteSpace(queueId))
{
return(new MemcachedQueueItem[indexs.Length]);
}
string[] itemKeys = new string[indexs.Length];
for (var i = 0; i < indexs.Length; i++)
{
itemKeys[i] = BuildItemIndexKey(queueId, indexs[i] <= 0 ? 0 : (ulong)indexs[i]);
}
var client = MemcachedCacheHelper.GetClientInstance();
var list = client.Get(itemKeys);
if (list == null || list.Length <= 0)
{
return(new MemcachedQueueItem[indexs.Length]);
}
MemcachedQueueItem[] rstList = new MemcachedQueueItem[indexs.Length];
for (uint i = 0; i < indexs.Length; i++)
{
var obj = (list == null || i >= list.Length) ? null : list[i];
rstList[i] = obj as MemcachedQueueItem;
}
return(rstList);
}
