/// <summary>
/// 根据key查询缓存信息
/// </summary>
/// <param name="key">HttpRequest唯一key</param>
/// <returns>Html</returns>
public CacheInfo Query(string key)
{
GetRealPath();
FileInfo fileinfo = new FileInfo(GetPath(key));
if (fileinfo.Exists)
{
var info = new CacheInfo();
info.StoreTime = fileinfo.LastWriteTime;
info.Size = fileinfo.Length;
return info;
}
return null;
}
public void Save(string key, Stream repInfo)
{
Cache[key] = repInfo;
CacheInfo info = null;
if (infos.ContainsKey(key))
{
info = infos[key];
}
else
{
info = new CacheInfo();
}
info.Size = repInfo.Length;
info.StoreTime = DateTime.Now;
infos[key] = info;
}
/// <summary>
/// 根据请求信息，生成实际的sql语句
/// </summary>
/// <param name="req"></param>
/// <returns></returns>
private String buildSql(System.Web.HttpRequest req, CacheInfo info)
{
String sql = Sql;
foreach (var item in Values)
{
var value = req.QueryString[item];
if (!String.IsNullOrEmpty(value))
{
sql = sql.Replace("GET[" + item + "]", value);
}
else
{
LogHelp.Warn("SqlExpire error:" + "配置了Get变量" + item + "，在Request.QueryString中确找不到");
}
}
sql = sql.Replace("[STORETIME]", info.StoreTime.AddSeconds(3).ToString("yyyy-MM-dd HH:mm:ss"));
sql = sql.Replace("[LENGTH]", info.Size.ToString());
sql = sql.Replace("[KEY]", info.Key);
return sql;
}
public bool IsExpire(HttpRequest req, CacheInfo info)
{
return info == null || (DateTime.Now - info.StoreTime).TotalSeconds > _second;
}
public bool IsExpire(System.Web.HttpRequest req, CacheInfo info)
{
return info == null || (DateTime.Now - info.StoreTime).TotalSeconds > _second || innerSqlExpire(req, info);
}
/// <summary>
/// 根据请求及配置的sql语句，查询数据库是否有记录，如果有记录代表已过期，反之亦然
/// </summary>
/// <param name="req"></param>
/// <param name="info"></param>
/// <returns></returns>
private bool innerSqlExpire(System.Web.HttpRequest req, CacheInfo info)
{
var sql = buildSql(req, info);
var isExipre = false;
if (!String.IsNullOrEmpty(ConnStr))
{
using (var conn = GetConn())
{
var comm = conn.CreateCommand();
comm.CommandText = sql;
isExipre = comm.ExecuteReader().HasRows;
}
}
return isExipre;
}
public bool IsExpire(HttpRequest req, CacheInfo info)
{
return(info == null || (DateTime.Now - info.StoreTime).TotalSeconds > _second);
}
public bool IsExpire(System.Web.HttpRequest req, CacheInfo info)
{
return(info == null || (DateTime.Now - info.StoreTime).TotalSeconds > _second || innerSqlExpire(req, info));
}
/// <summary>
/// 缓存没过期，直接输出缓存
/// </summary>
/// <param name="context"></param>
/// <param name="key"></param>
/// <param name="info"></param>
private void ResponceCache(HttpContext context, string key, CacheInfo info)
{
var req = context.Request;
var rep = context.Response;
string time = info.StoreTime.ToString("r");
if (req.Headers["If-Modified-Since"] == time)
{
rep.StatusCode = (int)System.Net.HttpStatusCode.NotModified;
LogHelp.Info("cache hit 304 " + req.RawUrl);
}
else
{
var httpInfo = new HttpInfo();
var _stream = Store.Get(key);
int headEndPosition = 0;
string firstLine = "";
httpInfo.Headers = HttpParseHelp.ParseHeader(_stream, ref headEndPosition, ref firstLine);
rep.StatusCode = ParseRespondCode(firstLine);
if (rep.StatusCode == 200)
{
rep.AppendHeader("Last-Modified", time);
}
httpInfo.Content = _stream;
OutResponse(req, rep, httpInfo);
LogHelp.Info("cache hit html " + req.RawUrl);
}
context.ApplicationInstance.CompleteRequest();
}
