public ShortUrlResult Create(string longUrl, string baseUrl)
{
var result = new ShortUrlResult {
Code = 0
};
var md5 = Md5(longUrl);
var hadMap = _dictMaps.FirstOrDefault(d => d.Value.Md5 == md5);
if (hadMap.Value != null)
{
result.ShortUrl = $"{baseUrl}/{hadMap.Value.ShortUrl}";
return(result);
}
lock (Locker) {
using (var dc = new ShortUrlContext()) {
var umTmp = dc.UrlMaps.FirstOrDefault(d => d.Md5 == md5);
if (umTmp != null)
{
ChangeRate(umTmp);
result.ShortUrl = umTmp.ShortUrl;
return(result);
}
if (_maxRecord == null)
{
_maxRecord = new MaxRecord {
Id = Guid.NewGuid(),
Status = 0,
No = 1,
LastChange = DateTime.Now
};
dc.MaxRecords.Add(_maxRecord);
}
else
{
_maxRecord.No += 1;
_maxRecord.LastChange = DateTime.Now;
var old = dc.MaxRecords.Find(_maxRecord.Id);
dc.Entry(old).CurrentValues.SetValues(_maxRecord);
}
var um = new UrlMap {
Id = Guid.NewGuid(),
LongUrl = longUrl,
ShortUrl = Encrypt(_maxRecord.No),
Md5 = md5,
Status = (int)EntityStatus.Init,
LastChange = DateTime.Now
};
dc.UrlMaps.Add(um);
dc.SaveChanges();
ChangeRate(um);
result.ShortUrl = $"{baseUrl}/{um.ShortUrl}";
return(result);
}
}
}
private Service()
{
using (var dc = new ShortUrlContext()) {
_maxRecord = dc.MaxRecords.FirstOrDefault();
_dictMaps = new Dictionary <string, UrlMap>();
var maps = dc.UrlMaps.Where(d => d.Status < 1000).OrderByDescending(d => d.LastChange).Take(100);
foreach (var map in maps)
{
_dictMaps.Add(map.ShortUrl, map);
}
}
}