// Removes anime to withhold from animeList and returns the withheld anime. This is only used in debug mode
private Dictionary <int, MalListEntry> WithholdAnime(AnimeRecsInputJson input, Dictionary <int, MalListEntry> animeList)
{
Dictionary <int, MalListEntry> animeWithheld = new Dictionary <int, MalListEntry>();
foreach (int animeIdToWithhold in input.AnimeIdsToWithhold)
{
if (animeList.ContainsKey(animeIdToWithhold))
{
animeWithheld[animeIdToWithhold] = animeList[animeIdToWithhold];
animeList.Remove(animeIdToWithhold);
}
}
if (input.PercentOfAnimeToWithhold > 0m)
{
int numAnimesToWithhold = (int)(animeList.Count * (input.PercentOfAnimeToWithhold / 100));
Random rng = new Random();
List <int> animeIdsToWithhold = animeList.Keys.OrderBy(animeId => rng.Next()).Take(numAnimesToWithhold).ToList();
foreach (int animeIdToWithhold in animeIdsToWithhold)
{
animeWithheld[animeIdToWithhold] = animeList[animeIdToWithhold];
animeList.Remove(animeIdToWithhold);
}
}
return(animeWithheld);
}
public async Task <IActionResult> GetRecs([FromBody] AnimeRecsInputJson input,
[FromServices] IOptionsSnapshot <Config.RecommendationsConfig> recConfig,
[FromServices] IMyAnimeListApiFactory malApiFactory, [FromServices] IAnimeRecsClientFactory recClientFactory,
[FromServices] IAnimeRecsDbConnectionFactory dbConnFactory, [FromServices] IRazorViewEngine viewEngine,
[FromServices] ITempDataProvider tempProvider)
{
if (!ModelState.IsValid)
{
AjaxError error = new AjaxError(ModelState);
_logger.LogDebug("Invalid input received for GetRecs: {0}", error.Message);
return(BadRequest(error));
}
if (input.RecSourceName == null)
{
input.RecSourceName = recConfig.Value.DefaultRecSource;
}
try
{
MalUserLookupResults userLookup = await GetUserLookupAsync(input, malApiFactory).ConfigureAwait(false);
Dictionary <int, MalListEntry> animeList = new Dictionary <int, MalListEntry>();
foreach (MyAnimeListEntry listEntry in userLookup.AnimeList)
{
animeList[listEntry.AnimeInfo.AnimeId] = new AnimeRecs.RecEngine.MAL.MalListEntry((byte?)listEntry.Score, listEntry.Status, (short)listEntry.NumEpisodesWatched);
}
Dictionary <int, MalListEntry> animeWithheld = WithholdAnime(input, animeList);
MalRecResults <IEnumerable <IRecommendation> > recResults = await GetRecommendationsAsync(input, recConfig.Value, animeList, animeWithheld, recClientFactory).ConfigureAwait(false);
GetRecsViewModel viewModel = new GetRecsViewModel(
results: recResults,
userId: userLookup.UserId,
userName: userLookup.CanonicalUserName,
userLookup: userLookup,
userAnimeList: animeList,
maximumRecommendationsToReturn: recConfig.Value.MaximumRecommendationsToReturn,
maximumRecommendersToReturn: recConfig.Value.MaximumRecommendersToReturn,
animeWithheld: animeWithheld,
dbConnectionFactory: dbConnFactory
);
RecResultsAsHtmlJson resultsJson = await GetResultHtmlAsync(viewModel, input, viewEngine, tempProvider).ConfigureAwait(false);
return(Ok(resultsJson));
}
catch (ShortCircuitException ex)
{
return(ex.Result);
}
}
private async Task <MalUserLookupResults> GetUserLookupAsync(AnimeRecsInputJson input, IMyAnimeListApiFactory malApiFactory)
{
using (IMyAnimeListApi malApi = malApiFactory.GetMalApi())
{
_logger.LogInformation("Getting MAL list for user {0}.", input.MalName);
MalUserLookupResults userLookup;
try
{
userLookup = await malApi.GetAnimeListForUserAsync(input.MalName).ConfigureAwait(false);
_logger.LogInformation("Got MAL list for user {0}.", input.MalName);
return(userLookup);
}
catch (MalUserNotFoundException)
{
_logger.LogInformation("User {0} not found.", input.MalName);
AjaxError error = new AjaxError(AjaxError.NoSuchMALUser, "No such MAL user.");
JsonResult result = Json(error);
result.StatusCode = 404;
throw new ShortCircuitException(result);
}
}
}
private async Task <RecResultsAsHtmlJson> GetResultHtmlAsync(GetRecsViewModel viewModel, AnimeRecsInputJson input,
IRazorViewEngine viewEngine, ITempDataProvider tempProvider)
{
// Support detailed results for the AnimeRecs recommendation type
string viewName;
if (viewModel.Results.RecommendationType.Equals(AnimeRecs.RecService.DTO.RecommendationTypes.AnimeRecs) && input.DisplayDetailedResults)
{
viewName = viewModel.Results.RecommendationType + "_complex";
}
else
{
viewName = viewModel.Results.RecommendationType;
}
IView view;
ViewEngineResult viewSearchResult = viewEngine.FindView(ControllerContext, viewName, isMainPage: false);
// Try to use a view specific for the recommendation type, fall back to the generic view if no specific view exists.
if (viewSearchResult.Success)
{
view = viewSearchResult.View;
}
else
{
string fallbackViewName = "Fallback";
ViewEngineResult fallbackViewSearchResult = viewEngine.FindView(ControllerContext, fallbackViewName, isMainPage: false);
if (!fallbackViewSearchResult.Success)
{
throw new Exception($"Failed to find fallback view named {fallbackViewName}.");
}
view = fallbackViewSearchResult.View;
}
// Render the view to a string
using (StringWriter writer = new StringWriter())
{
ViewDataDictionary viewDictionary = new ViewDataDictionary(new EmptyModelMetadataProvider(), new ModelStateDictionary())
{
Model = viewModel
};
TempDataDictionary tempDataDictionary = new TempDataDictionary(HttpContext, tempProvider);
ViewContext viewcontext = new ViewContext(ControllerContext, view, viewDictionary, tempDataDictionary,
writer, new HtmlHelperOptions());
await view.RenderAsync(viewcontext).ConfigureAwait(false);
string renderedHtml = writer.ToString();
return(new RecResultsAsHtmlJson(renderedHtml));
}
}
private async Task <MalRecResults <IEnumerable <IRecommendation> > > GetRecommendationsAsync(AnimeRecsInputJson input,
Config.RecommendationsConfig recConfig, Dictionary <int, MalListEntry> animeList,
Dictionary <int, MalListEntry> animeWithheld, IAnimeRecsClientFactory recClientFactory)
{
int numRecsToTryToGet = recConfig.MaximumRecommendationsToReturn;
if (animeWithheld.Count > 0)
{
// Get rating prediction information about all anime if in debug mode and withholding anime.
// For all currently implemented algorithms, this does not cause a performance problem.
numRecsToTryToGet = 100000;
}
using (AnimeRecsClient recClient = recClientFactory.GetClient(input.RecSourceName))
{
MalRecResults <IEnumerable <IRecommendation> > recResults;
try
{
if (input.GoodPercentile != null)
{
decimal targetFraction = input.GoodPercentile.Value / 100;
_logger.LogInformation("Querying rec source {0} for {1} recommendations for {2} using target of top {3}%.",
input.RecSourceName, numRecsToTryToGet, input.MalName, targetFraction);
recResults = await recClient.GetMalRecommendationsWithFractionTargetAsync(animeList,
input.RecSourceName, numRecsToTryToGet, targetFraction,
TimeSpan.FromMilliseconds(recConfig.TimeoutMilliseconds), CancellationToken.None).ConfigureAwait(false);
}
else if (input.GoodCutoff != null)
{
_logger.LogInformation("Querying rec source {0} for {1} recommendations for {2} using target of {3}.",
input.RecSourceName, numRecsToTryToGet, input.MalName, input.GoodCutoff.Value);
recResults = await recClient.GetMalRecommendationsAsync(animeList, input.RecSourceName,
numRecsToTryToGet, input.GoodCutoff.Value, TimeSpan.FromMilliseconds(recConfig.TimeoutMilliseconds),
CancellationToken.None).ConfigureAwait(false);
}
else
{
decimal targetFraction = recConfig.DefaultTargetPercentile / 100;
_logger.LogInformation("Querying rec source {0} for {1} recommendations for {2} using default target of top {3}%.",
input.RecSourceName, numRecsToTryToGet, input.MalName, targetFraction);
recResults = await recClient.GetMalRecommendationsWithFractionTargetAsync(animeList,
input.RecSourceName, numRecsToTryToGet, targetFraction,
TimeSpan.FromMilliseconds(recConfig.TimeoutMilliseconds), CancellationToken.None)
.ConfigureAwait(false);
}
}
catch (AnimeRecs.RecService.DTO.RecServiceErrorException ex)
{
if (ex.Error.ErrorCode == AnimeRecs.RecService.DTO.ErrorCodes.Maintenance)
{
_logger.LogInformation("Could not service recommendation request for {0}. The rec service is currently undergoing maintenance.",
input.MalName);
AjaxError error = new AjaxError(AjaxError.InternalError, "The site is currently undergoing scheduled maintenance. Check back in a few minutes.");
JsonResult result = Json(error);
result.StatusCode = 500;
throw new ShortCircuitException(result);
}
else
{
throw;
}
}
_logger.LogInformation("Got results from rec service for {0}.", input.MalName);
return(recResults);
}
}
