/// <summary>
/// 获取从库的连接字符串( 读取规则，当所有的从库无法使用的时候读取返回主库的连接字符串)
/// </summary>
/// <param name="dbContextType"></param>
/// <returns></returns>
private string SlaveConnection(Type dbContextType)
{
//获取从库的信息
var slaveList = SlavePools.slaveConnec.Where(a => a.Key == dbContextType).Select(a => a.Value).FirstOrDefault();
SlaveDbConnection slaveInfo = null;
if (slaveList != null && slaveList.Count() > 0)
{
slaveInfo = slaveList.Where(a => a.IsAvailable).OrderBy(a => Guid.NewGuid()).FirstOrDefault();
}
if (slaveInfo == null)
{
return(options.WriteReadConnectionString);
}
//进行心跳检查
var isBeat = SlavePools.HeartBeatCheck(dbContextType, slaveInfo);
if (isBeat == false)
{
return(SlaveConnection(dbContextType));
}
return(slaveInfo.ConnectionString);
}
/// <summary>
/// 执行心跳检查 检查从库是否正在运行
/// </summary>
/// <param name="slaveConnections">从库的连接字符串</param>
/// <param name="dbcontext">上下文类型</param>
internal static bool HeartBeatCheck(Type dbcontext, SlaveDbConnection slaveConnections)
{
using var tcpClient = new TcpClient();
try
{
//连接tcp服务器
tcpClient.Connect(slaveConnections.HostName, slaveConnections.Port);
}
catch (Exception)
{
slaveConnec.Where(a => a.Key == dbcontext).Select(a => a.Value).FirstOrDefault()?.ForEach(item =>
{
if (item == slaveConnections)
{
item.IsAvailable = false;
}
});
logger.LogInformation($"SlavePools:当前{slaveConnections.ConnectionString}从库的无法连接");
return(false);
}
return(true);
}
