public IActionResult MoreById(string id)
{
bool invalidId = id == null || id == "";
SelectedTweet st = _context.SelectedTweets.FirstOrDefault(x => x.TweetId == id);
if (invalidId || st == null)
{
return(BadRequest());
}
return(Ok(new TweetIdAndStateVM[] { new TweetIdAndStateVM(st) }));
}
public IActionResult Update([FromBody] UpdatedStateBM[] newStates)
{
if (newStates == null || newStates.Length == 0)
{
return(BadRequest());
}
foreach (UpdatedStateBM u in newStates)
{
SelectedTweet s = _context.SelectedTweets.FirstOrDefault(x => x.TweetId == u.TweetId);
if (s != null)
{
s.CurrentState = u.NewState;
s.CheckedAt = DateTime.UtcNow;
}
_context.SaveChanges();
}
return(Ok());
}
/// <summary>
/// Checks the tweets for a given contributor, that is, gets his last 50 tweets,
/// selects the five best ( those with most likes/retweets) and if they are not in the
/// database, add them, if they were already added, update them.
/// </summary>
/// <param name="contributor">The Contributor whose tweets will be checked.</param>
public async Task CheckTweets(Contributor contributor)
{
const int LAST_N_TWEETS = 50;
Tweet[] tweets = null;
// 1) Try and get the last 50 tweets:
string screen_name = contributor?.TwitterUser?.screen_name;
if (screen_name == null)
{
throw new ArgumentNullException();
}
try
{
tweets = await _twitterService.GetTweets(screen_name, LAST_N_TWEETS);
}
catch (Exception e)
{
_logger.LogError(e.ToString());
}
using (var serviceScope = _services.CreateScope())
{
var context = serviceScope.ServiceProvider.GetRequiredService <MyDbContext>();
Contributor c = context.Contributors.Single(p => p.ContributorId == contributor.ContributorId);
//2) always update contributors lastChecked date, even if one fails to get tweets:
c.LastUpdate = DateTime.UtcNow;
if (tweets != null && tweets.Length > 0)
{
const int HOW_MANY_BEST_TWEETS = 5;
//3) if tweets were successfully retrieved, select the five best ones:
Tweet[] best = tweets
.OrderByDescending(t => t.favorite_count + t.retweet_count)
.Where(t => t.favorite_count + t.retweet_count > 0)
.Take(HOW_MANY_BEST_TWEETS).ToArray();
context.Entry(c).Collection(x => x.SelectedTweets).Load();
string[] existingIds = c.SelectedTweets.Select(t => t.TweetId).ToArray();
// 4) Add selected tweets to database, as SelectedTweets:
foreach (var t in best)
{
if (existingIds.Contains(t.id_str))
{
//Update Tweet's selectedAt date, if it already exists and it is still unchecked:
SelectedTweet selectedTweetedFromDb = c.SelectedTweets.First(x => x.TweetId == t.id_str);
if (selectedTweetedFromDb.CurrentState == PublishingState.Unchecked)
{
selectedTweetedFromDb.SelectedAt = DateTime.UtcNow;
context.Update(t);
}
}
else
{
//Add if it does not exist yet:
SelectedTweet newSelectedTweet = new SelectedTweet();
newSelectedTweet.Tweet = t;
newSelectedTweet.SelectedAt = DateTime.UtcNow;
c.SelectedTweets.Add(newSelectedTweet);
}
}
}
await context.SaveChangesAsync();
}
}
