public UserSubscription AddNewFeed(string feedUrl, User user)
{
var feedHashCode = feedUrl.GetHashCode();
var subscription = _dbContext.Subscriptions.SingleOrDefault(x => x.Hash == feedHashCode);
if (subscription == null)
{
subscription = AddSubscription(feedUrl, user);
}
else
{
var alreadySubscribed = subscription.UserSubscriptions.Any(x => x.User.Email == user.Email);
if (alreadySubscribed)
{
throw new BralekTechnicalException("ALREADY_SUBSCRIBED", null);
}
}
var userSubscription = new UserSubscription
{
AddedOnUTC = DateTime.UtcNow,
Subscription = subscription,
UpdatedOnUTC = DateTime.UtcNow,
User = user,
UnreadItems = subscription.SubscriptionPosts.Count()
};
_dbContext.UserSubscriptions.Add(userSubscription);
_dbContext.SaveChanges();
return userSubscription;
}
private Subscription AddSubscription(string feedUrl, User user)
{
try
{
var uri = new Uri(feedUrl);
var feed = GenericSyndicationFeed.Create(uri,
new SyndicationResourceLoadSettings { AutoDetectExtensions = true, Timeout = new TimeSpan(0, 0, 3) });
var feedHashCode = feedUrl.GetHashCode();
var subscription = new Subscription
{
AddedOnUTC = DateTime.UtcNow,
AddedBy = user,
FeedUrl = feedUrl,
Hash = feedHashCode,
Title = feed.Title,
};
switch (feed.Format)
{
case SyndicationContentFormat.Atom:
var atom = (AtomFeed)feed.Resource;
subscription.Title = GetAtomSubscriptionTitle(atom);
GetAtomFeedItems(atom, subscription);
break;
case SyndicationContentFormat.Rss:
var rss = (RssFeed)feed.Resource;
subscription.SiteUrl = rss.Channel.Link.ToString();
GetRssFeedItems(rss, subscription);
break;
case SyndicationContentFormat.None:
throw new BralekTechnicalException("NO_RSS_FORMAT", null);
default:
throw new BralekTechnicalException("RSS_UNKNOWN_FORMAT", null);
}
_dbContext.Subscriptions.Add(subscription);
return subscription;
}
catch (UriFormatException ex)
{
throw new BralekTechnicalException("ADD_FEED_URI_ERROR", ex);
}
catch (WebException ex)
{
throw new BralekTechnicalException("FEED_READ_ERROR", ex);
}
catch (XmlException ex)
{
throw new BralekTechnicalException("FEED_XML_ERROR", ex);
}
}
