我正在尝试将这些查询的结果并行地获取到redis(使用stackexchange C#客户端),但不知怎的,我正在运行死锁并且不知道在哪里
检索数据的方法:
public LiveData Get(string sessionId)
{
return GetAsync(sessionId).Result;
}
private async Task<LiveData> GetAsync(string sessionId)
{
var basketTask = GetBasketAsync(sessionId);
var historyTask = GetHistoryAsync(sessionId);
var capturedDataTask = GetCapturedDataAsync(sessionId);
var basket = await basketTask;
var history = await historyTask;
var capturedData = await capturedDataTask;
return new LiveData
{
Basket = basket.IsNullOrEmpty
? new List<Product>()
: JsonConvert.DeserializeObject<List<Product>>(basket),
History = history.Select(cachedProduct
=> JsonConvert.DeserializeObject<Product>(cachedProduct.Value.ToString())).ToList(),
CapturedData = capturedData.ToDictionary<HashEntry, string, object>(
hash => hash.Name, hash => JsonConvert.DeserializeObject(hash.Value))
};
}
从redis获取缓存数据的方法是:
private async Task<RedisValue> GetBasketAsync(string key)
{
key = $"{key}{BasketSuffix}";
var redisDb = RedisConnection.Connection.GetDatabase();
redisDb.KeyExpireAsync(key, _expire);
return await redisDb.StringGetAsync(key);
}
private async Task<HashEntry[]> GetHistoryAsync(string key)
{
key = $"{key}{HistorySuffix}";
var redisDb = RedisConnection.Connection.GetDatabase();
redisDb.KeyExpireAsync(key, _expire);
return await redisDb.HashGetAllAsync(key);
}
private async Task<HashEntry[]> GetCapturedDataAsync(string key)
{
key = $"{key}{CapturedDataSuffix}";
var redisDb = RedisConnection.Connection.GetDatabase();
redisDb.KeyExpireAsync(key, _expire);
return await redisDb.HashGetAllAsync(key);
}
我认为像这样调用KeyExpireAsync很好,只是因为它可以触发并忘记,但不确定是否可以相关(我尝试删除它并且它仍然被阻止)
答案 0 :(得分:3)
死锁的来源就是这个片段:
public LiveData Get(string sessionId)
{
return GetAsync(sessionId).Result;
}
相反,以正确的方式调用它&#34;一直异步&#34;:
public async Task<LiveData> Get(string sessionId)
{
return await GetAsync(sessionId);
}
调用.Result
会导致死锁,就像使用.Wait()
API一样。此外,从它的外观来看 - 需要等待.KeyExpireAsync
。
async Task<RedisValue> GetBasketAsync(string key)
{
key = $"{key}{BasketSuffix}";
var redisDb = RedisConnection.Connection.GetDatabase();
await redisDb.KeyExpireAsync(key, _expire);
return await redisDb.StringGetAsync(key);
}
我理解您在await
调用时未使用.KeyExpireAsync
关键字的思考过程,但如果我编写此代码,我肯定希望await
就像我演示的那样。这是一种代码气味,可以轻松避免。