public Task<ShortUrl> ShortenUrl(string longUrl, string ip, string segment = "") { return Task.Run(() => { using (var ctx = new ShortnrContext()) { ShortUrl url; url = ctx.ShortUrls.Where(u => u.LongUrl == longUrl).FirstOrDefault(); if (url != null) { return url; } if (!longUrl.StartsWith("http://") && !longUrl.StartsWith("https://")) { throw new ArgumentException("Invalid URL format"); } bool validateUrl = false; bool.TryParse(ConfigurationManager.AppSettings["ValidateRemoteUrl"], out validateUrl); if (validateUrl) { Uri urlCheck = new Uri(longUrl); HttpWebRequest request = (HttpWebRequest)WebRequest.Create(urlCheck); request.Timeout = 10000; try { HttpWebResponse response = (HttpWebResponse)request.GetResponse(); } catch (Exception) { throw new ShortnrNotFoundException(); } } int cap = 0; int.TryParse(ConfigurationManager.AppSettings["MaxNumberShortUrlsPerHour"], out cap); if(cap > 0) { DateTime dateToCheck = DateTime.Now.Subtract(new TimeSpan(1, 0, 0)); int count = ctx.ShortUrls.Where(u => u.Ip == ip && u.Added >= dateToCheck).Count(); if (cap != 0 && count > cap) { throw new ArgumentException("Your hourly limit has exceeded"); } } if (!string.IsNullOrEmpty(segment)) { if (ctx.ShortUrls.Where(u => u.Segment == segment).Any()) { throw new ShortnrConflictException(); } if (segment.Length > 20 || !Regex.IsMatch(segment, @"^[A-Za-z\d_-]+$")) { throw new ArgumentException("Malformed or too long segment"); } } else { segment = this.NewSegment(); } if (string.IsNullOrEmpty(segment)) { throw new ArgumentException("Segment is empty"); } url = new ShortUrl() { Added = DateTime.Now, Ip = ip, LongUrl = longUrl, NumOfClicks = 0, Segment = segment }; ctx.ShortUrls.Add(url); ctx.SaveChanges(); return url; } }); }
public Task<Stat> Click(string segment, string referer, string ip) { return Task.Run(() => { using (var ctx = new ShortnrContext()) { ShortUrl url = ctx.ShortUrls.Where(u => u.Segment == segment).FirstOrDefault(); if (url == null) { throw new ShortnrNotFoundException(); } url.NumOfClicks = url.NumOfClicks + 1; Stat stat = new Stat() { ClickDate = DateTime.Now, Ip = ip, Referer = referer, ShortUrl = url }; ctx.Stats.Add(stat); ctx.SaveChanges(); return stat; } }); }
private string NewSegment() { using (var ctx = new ShortnrContext()) { int i = 0; int segmentSize = 0; if(!int.TryParse(ConfigurationManager.AppSettings["SegmentSize"], out segmentSize)) { segmentSize = 6; } while (i < 30) { string segment = Guid.NewGuid().ToString().Replace("-","").Substring(0, segmentSize); if (!ctx.ShortUrls.Where(u => u.Segment == segment).Any()) { return segment; } i++; } return string.Empty; } }
private string NewSegment() { using (var ctx = new ShortnrContext()) { int i = 0; while (true) { string segment = Guid.NewGuid().ToString().Substring(0, 6); if (!ctx.ShortUrls.Where(u => u.Segment == segment).Any()) { return segment; } if (i > 30) { break; } i++; } return string.Empty; } }