Faster tag view in UI for large libraries

(cherry picked from commit b050e1d2eb3bff9e28e7a1545d121be091789308)

Closes #2571

src/NzbDrone.Core/Books/Repositories/AuthorRepository.cs

@@ -13,6 +13,7 @@ namespace NzbDrone.Core.Books
         Author FindByName(string cleanName);
         Author FindById(string foreignAuthorId);
         Dictionary<int, string> AllAuthorPaths();
+        Dictionary<int, List<int>> AllAuthorTags();
         Author GetAuthorByMetadataId(int authorMetadataId);
         List<Author> GetAuthorsByMetadataId(IEnumerable<int> authorMetadataId);
     }
@@ -65,6 +66,15 @@ namespace NzbDrone.Core.Books
             }
         }
 
+        public Dictionary<int, List<int>> AllAuthorTags()
+        {
+            using (var conn = _database.OpenConnection())
+            {
+                var strSql = "SELECT \"Id\" AS \"Key\", \"Tags\" AS \"Value\" FROM \"Authors\" WHERE \"Tags\" IS NOT NULL";
+                return conn.Query<KeyValuePair<int, List<int>>>(strSql).ToDictionary(x => x.Key, x => x.Value);
+            }
+        }
+
         public Author GetAuthorByMetadataId(int authorMetadataId)
         {
             return Query(s => s.AuthorMetadataId == authorMetadataId).SingleOrDefault();

src/NzbDrone.Core/Books/Services/AuthorService.cs

@@ -24,6 +24,7 @@ namespace NzbDrone.Core.Books
         List<Author> GetReportCandidates(string reportTitle);
         void DeleteAuthor(int authorId, bool deleteFiles, bool addImportListExclusion = false);
         List<Author> GetAllAuthors();
+        Dictionary<int, List<int>> GetAllAuthorTags();
         List<Author> AllForTag(int tagId);
         Author UpdateAuthor(Author author);
         List<Author> UpdateAuthors(List<Author> authors, bool useExistingRelativeFolder);
@@ -185,6 +186,11 @@ namespace NzbDrone.Core.Books
             return _cache.Get("GetAllAuthors", () => _authorRepository.All().ToList(), TimeSpan.FromSeconds(30));
         }
 
+        public Dictionary<int, List<int>> GetAllAuthorTags()
+        {
+            return _authorRepository.AllAuthorTags();
+        }
+
         public Dictionary<int, string> AllAuthorPaths()
         {
             return _authorRepository.AllAuthorPaths();

src/NzbDrone.Core/Tags/TagService.cs

@@ -106,7 +106,7 @@ namespace NzbDrone.Core.Tags
             var importLists = _importListFactory.All();
             var notifications = _notificationFactory.All();
             var restrictions = _releaseProfileService.All();
-            var authors = _authorService.GetAllAuthors();
+            var authors = _authorService.GetAllAuthorTags();
             var indexers = _indexerService.All();
             var rootFolders = _rootFolderService.All();
 
@@ -122,7 +122,7 @@ namespace NzbDrone.Core.Tags
                     ImportListIds = importLists.Where(c => c.Tags.Contains(tag.Id)).Select(c => c.Id).ToList(),
                     NotificationIds = notifications.Where(c => c.Tags.Contains(tag.Id)).Select(c => c.Id).ToList(),
                     RestrictionIds = restrictions.Where(c => c.Tags.Contains(tag.Id)).Select(c => c.Id).ToList(),
-                    AuthorIds = authors.Where(c => c.Tags.Contains(tag.Id)).Select(c => c.Id).ToList(),
+                    AuthorIds = authors.Where(c => c.Value.Contains(tag.Id)).Select(c => c.Key).ToList(),
                     IndexerIds = indexers.Where(c => c.Tags.Contains(tag.Id)).Select(c => c.Id).ToList(),
                     RootFolderIds = rootFolders.Where(c => c.DefaultTags.Contains(tag.Id)).Select(c => c.Id).ToList()
                 });