public static void PrepareRatings(IMemoryCache cache, BlogContext db, IEnumerable <int> blogs)
{
var ids = new HashSet <int>(blogs);
var result = new Dictionary <int, int>(ids.Count());
var ratingCache = cache.Get <ConcurrentDictionary <int, BlogRatingDisplay> >("Rating~") ?? new ConcurrentDictionary <int, BlogRatingDisplay>();
var uncached = ids.Where(i => !ratingCache.ContainsKey(i));
if (uncached.Count() > 0)
{
var rates = db.BlogRatings.Where(r => uncached.Contains(r.BlogID))
.Select(r => new { r.BlogID, r.value })
.GroupBy(r => r.BlogID)
.ToList()
.Select(r => new BlogRatingDisplay
{
BlogId = r.Key,
CountByRating = r.GroupBy(br => br.value).ToDictionary(v => v.Key, v => v.Count())
})
.ToDictionary(r => r.BlogId);
foreach (var id in uncached)
{
BlogRatingDisplay br;
if (!rates.TryGetValue(id, out br))
{
br = new BlogRatingDisplay {
BlogId = id
};
}
ratingCache.TryAdd(id, br);
}
}
cache.Set("Rating~", ratingCache, new MemoryCacheEntryOptions {
Priority = CacheItemPriority.High
});
}
public BlogRatingDisplay GetRating(int id, bool fromcache = true)
{
var ratings = _cache.Get <ConcurrentDictionary <int, BlogRatingDisplay> >("Rating~") ?? new ConcurrentDictionary <int, BlogRatingDisplay>();
if (!ratings.TryGetValue(id, out BlogRatingDisplay rating) || fromcache == false)
{
var rates = _db.BlogRatings.Where(r => r.BlogID == id);
rating = new BlogRatingDisplay
{
BlogId = id,
CountByRating = rates.GroupBy(r => r.value).ToDictionary(v => v.Key, v => v.Count()),
};
ratings.AddOrUpdate(id, rating, (i, old) => rating);
_cache.Set("Rating~", ratings, new MemoryCacheEntryOptions {
Priority = CacheItemPriority.High
});
}
return(rating);
}
