/// <inheritdoc />
public async Task <List <PopularCategoryViewModel> > GetPopularCategories()
{
using var scope = ServiceProvider.CreateScope();
var context = scope.ServiceProvider.GetRequiredService <ApplicationContext>();
var categoriesEnumerable = context.Categories.AsSplitQuery().AsNoTracking().AsEnumerable();
var categories = categoriesEnumerable.Where(x => CategoryRecords.Any(e => x.Id == e.Record))
.OrderBy(x => CategoryRecords.FirstOrDefault(c => x.Id == c.Record).Score).ToList();
// If there are no popular categories get all of them.
if (!categories.Any())
{
return((await context.Categories.AsNoTracking().ToListAsync())
.Select(x => new PopularCategoryViewModel()
{
Id = x.Id,
Name = x.Name,
Score = 0
}).ToList());
}
return(categories.Select(x => new PopularCategoryViewModel()
{
Id = x.Id,
Name = x.Name,
Score = CategoryRecords.Find(c => x.Id == c.Record).Score
}).ToList());
}
/// <inheritdoc />
public async Task PopulariseCategory(CancellationToken cancellationToken, Guid categoryId, DateTime created)
{
if (!cancellationToken.IsCancellationRequested)
{
Logger.LogInformation("Popularising category {Id}", categoryId);
var popularityRecord = CategoryRecords.FirstOrDefault(x => x.Record == categoryId);
// if the category is already popular
if (popularityRecord != null)
{
Logger.LogInformation("Category {Id} is already popular, making more popular", categoryId);
popularityRecord.Updated = created;
popularityRecord.Score++;
}
else
{
using var scope = ServiceProvider.CreateScope();
var context = scope.ServiceProvider.GetRequiredService <ApplicationContext>();
var c = await context.Categories.FirstOrDefaultAsync(x => x.Id == categoryId, cancellationToken);
if (c == null)
{
Logger.LogInformation("Category not found");
return;
}
CategoryRecords.Add(new PopularityRecord
{
Added = created,
Updated = created,
Record = categoryId,
Score = 1
});
}
// sends popular categories to all web-socket clients
await PopularityHubContext.Clients.All.SendAsync("categories", await GetPopularCategories());
Logger.LogInformation("Popularised category {Id}", categoryId);
}
}
