Faster languages

src/Umbraco.Core/Cache/FullDataSetRepositoryCachePolicy.cs

@@ -156,7 +156,7 @@ namespace Umbraco.Core.Cache
         }
 
         // does NOT clone anything, so be nice with the returned values
-        private IEnumerable<TEntity> GetAllCached(Func<TId[], IEnumerable<TEntity>> performGetAll)
+        internal IEnumerable<TEntity> GetAllCached(Func<TId[], IEnumerable<TEntity>> performGetAll)
         {
             // try the cache first
             var all = Cache.GetCacheItem<DeepCloneableList<TEntity>>(GetEntityTypeCacheKey());

src/Umbraco.Core/Persistence/Repositories/ILanguageRepository.cs

@@ -6,5 +6,8 @@ namespace Umbraco.Core.Persistence.Repositories
     {
         ILanguage GetByCultureName(string cultureName);
         ILanguage GetByIsoCode(string isoCode);
+
+        int GetIdByIsoCode(string isoCode);
+        string GetIsoCodeById(int id);
     }
 }

src/Umbraco.Core/Persistence/Repositories/Implement/LanguageRepository.cs

@@ -18,21 +18,24 @@ namespace Umbraco.Core.Persistence.Repositories.Implement
     /// </summary>
     internal class LanguageRepository : NPocoRepositoryBase<int, ILanguage>, ILanguageRepository
     {
+        private readonly Dictionary<string, int> _codeIdMap = new Dictionary<string, int>();
+        private readonly Dictionary<int, string> _idCodeMap = new Dictionary<int, string>();
+        private FullDataSetRepositoryCachePolicy<ILanguage, int> _cachePolicy;
+
         public LanguageRepository(IScopeAccessor scopeAccessor, CacheHelper cache, ILogger logger)
             : base(scopeAccessor, cache, logger)
         { }
 
         protected override IRepositoryCachePolicy<ILanguage, int> CreateCachePolicy()
         {
-            return new FullDataSetRepositoryCachePolicy<ILanguage, int>(GlobalIsolatedCache, ScopeAccessor, GetEntityId, /*expires:*/ false);
+            return _cachePolicy = new FullDataSetRepositoryCachePolicy<ILanguage, int>(GlobalIsolatedCache, ScopeAccessor, GetEntityId, /*expires:*/ false);
         }
 
         #region Overrides of RepositoryBase<int,Language>
 
         protected override ILanguage PerformGet(int id)
         {
-            //use the underlying GetAll which will force cache all domains
-            return GetMany().FirstOrDefault(x => x.Id == id);
+            throw new NotSupportedException(); // not required since policy is full dataset
         }
 
         protected override IEnumerable<ILanguage> PerformGetAll(params int[] ids)
@@ -47,8 +50,22 @@ namespace Umbraco.Core.Persistence.Repositories.Implement
             //even though legacy didn't sort, it should be by id
             sql.OrderBy<LanguageDto>(dto => dto.Id);
 
+            // get languages
+            var languages = Database.Fetch<LanguageDto>(sql).Select(ConvertFromDto).ToList();
 
-            return Database.Fetch<LanguageDto>(sql).Select(ConvertFromDto);
+            // initialize the code-id map
+            lock (_codeIdMap)
+            {
+                _codeIdMap.Clear();
+                _idCodeMap.Clear();
+                foreach (var language in languages)
+                {
+                    _codeIdMap[language.IsoCode] = language.Id;
+                    _idCodeMap[language.Id] = language.IsoCode;
+                }
+            }
+
+            return languages;
         }
 
         protected override IEnumerable<ILanguage> PerformGetByQuery(IQuery<ILanguage> query)
@@ -184,14 +201,40 @@ namespace Umbraco.Core.Persistence.Repositories.Implement
 
         public ILanguage GetByCultureName(string cultureName)
         {
-            //use the underlying GetAll which will force cache all languages
+            // use the underlying GetMany which will force cache all languages
+            // TODO we are cloning ALL in GetMany just to retrieve ONE, this is surely not optimized
             return GetMany().FirstOrDefault(x => x.CultureName.InvariantEquals(cultureName));
         }
 
         public ILanguage GetByIsoCode(string isoCode)
         {
-            //use the underlying GetAll which will force cache all languages
-            return GetMany().FirstOrDefault(x => x.IsoCode.InvariantEquals(isoCode));
+            _cachePolicy.GetAllCached(PerformGetAll); // ensure cache is populated, in a non-expensive way
+            var id = GetIdByIsoCode(isoCode);
+            return Get(id);
+        }
+
+        // fast way of getting an id for an isoCode - avoiding cloning
+        // _codeIdMap is rebuilt whenever PerformGetAll runs
+        public int GetIdByIsoCode(string isoCode)
+        {
+            _cachePolicy.GetAllCached(PerformGetAll); // ensure cache is populated, in a non-expensive way
+            lock (_codeIdMap)
+            {
+                if (_codeIdMap.TryGetValue(isoCode, out var id)) return id;
+            }
+            throw new ArgumentException($"Code {isoCode} does not correspond to an existing language.", nameof(isoCode));
+        }
+
+        // fast way of getting an isoCode for an id - avoiding cloning
+        // _idCodeMap is rebuilt whenever PerformGetAll runs
+        public string GetIsoCodeById(int id)
+        {
+            _cachePolicy.GetAllCached(PerformGetAll); // ensure cache is populated, in a non-expensive way
+            lock (_codeIdMap) // yes, we want to lock _codeIdMap
+            {
+                if (_idCodeMap.TryGetValue(id, out var isoCode)) return isoCode;
+            }
+            throw new ArgumentException($"Id {id} does not correspond to an existing language.", nameof(id),);
         }
     }
 }

src/Umbraco.Core/Services/ILocalizationService.cs

@@ -117,6 +117,11 @@ namespace Umbraco.Core.Services
         /// <returns><see cref="Language"/></returns>
         ILanguage GetLanguageByIsoCode(string isoCode);
 
+        /// <summary>
+        /// Gets a language identifier by its iso code.
+        /// </summary>
+        int GetLanguageIdByIsoCode(string isoCode);
+
         /// <summary>
         /// Gets all available languages
         /// </summary>

src/Umbraco.Core/Services/Implement/LocalizationService.cs

@@ -316,6 +316,15 @@ namespace Umbraco.Core.Services.Implement
             }
         }
 
+        /// <inheritdoc />
+        public int GetLanguageIdByIsoCode(string isoCode)
+        {
+            using (ScopeProvider.CreateScope(autoComplete: true))
+            {
+                return _languageRepository.GetIdByIsoCode(isoCode);
+            }
+        }
+
         /// <summary>
         /// Gets all available languages
         /// </summary>