adding cache

OpenCand.API/Program.cs

@@ -1,3 +1,4 @@
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.FileProviders;
 using OpenCand.API.Config;
 using OpenCand.API.Repository;
@@ -51,15 +52,21 @@ namespace OpenCand.API
 
 
             app.Run();
-        }
+        }        private static void SetupServices(WebApplicationBuilder builder)
-
-        private static void SetupServices(WebApplicationBuilder builder)
         {
             builder.Services.Configure<FotosSettings>(builder.Configuration.GetSection("FotosSettings"));
-            builder.Services.AddScoped<OpenCandRepository>();
+            builder.Services.AddMemoryCache();
-            builder.Services.AddScoped<CandidatoRepository>();
+            
-            builder.Services.AddScoped<BemCandidatoRepository>();
+            // Register repositories with IMemoryCache
-            builder.Services.AddScoped<DespesaReceitaRepository>();
+            builder.Services.AddScoped<OpenCandRepository>(provider =>
+                new OpenCandRepository(provider.GetRequiredService<IConfiguration>(), provider.GetService<IMemoryCache>()));
+            builder.Services.AddScoped<CandidatoRepository>(provider =>
+                new CandidatoRepository(provider.GetRequiredService<IConfiguration>(), provider.GetService<IMemoryCache>()));
+            builder.Services.AddScoped<BemCandidatoRepository>(provider =>
+                new BemCandidatoRepository(provider.GetRequiredService<IConfiguration>(), provider.GetService<IMemoryCache>()));
+            builder.Services.AddScoped<DespesaReceitaRepository>(provider =>
+                new DespesaReceitaRepository(provider.GetRequiredService<IConfiguration>(), provider.GetService<IMemoryCache>()));
+            
             builder.Services.AddScoped<OpenCandService>();
         }
     }

OpenCand.API/Repository/BaseRepository.cs

@@ -1,4 +1,4 @@
-using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Caching.Memory;
 using Npgsql;
 
 namespace OpenCand.Repository
@@ -7,11 +7,131 @@ namespace OpenCand.Repository
     {
         protected string ConnectionString { get; private set; }
         protected NpgsqlConnection? Connection { get; private set; }
+        protected readonly IMemoryCache? _cache;
 
-        public BaseRepository(IConfiguration configuration)
+        // Default cache settings
+        protected static readonly TimeSpan DefaultCacheExpiration = TimeSpan.FromDays(7);
+        protected static readonly CacheItemPriority DefaultCachePriority = CacheItemPriority.Normal;
+
+        public BaseRepository(IConfiguration configuration, IMemoryCache? cache = null)
         {
             ConnectionString = configuration["DatabaseSettings:ConnectionString"] ?? 
                 throw new ArgumentNullException("Connection string not found in configuration");
+            _cache = cache;
+        }
+        
+        /// <summary>
+        /// Generic method to get data from cache or execute a factory function if not cached
+        /// </summary>
+        /// <typeparam name="T">Type of data to cache</typeparam>
+        /// <param name="cacheKey">Unique cache key</param>
+        /// <param name="factory">Function to execute if data is not in cache</param>
+        /// <param name="expiration">Cache expiration time (optional, uses default if not provided)</param>
+        /// <param name="priority">Cache priority (optional, uses default if not provided)</param>
+        /// <returns>Cached or freshly retrieved data</returns>
+        protected async Task<T?> GetOrSetCacheAsync<T>(
+            string cacheKey,
+            Func<Task<T?>> factory,
+            TimeSpan? expiration = null,
+            CacheItemPriority? priority = null) where T : class
+        {
+            // If caching is not available, execute factory directly
+            if (_cache == null)
+            {
+                return await factory();
+            }
+
+            // Try to get cached data first
+            if (_cache.TryGetValue(cacheKey, out T? cachedData) && cachedData != null)
+            {
+                return cachedData;
+            }
+
+            // If not in cache, execute factory function
+            var result = await factory();
+            
+            // Only cache non-null results
+            if (result != null)
+            {
+                _cache.Set(cacheKey, result, new MemoryCacheEntryOptions
+                {
+                    SlidingExpiration = expiration ?? DefaultCacheExpiration,
+                    Priority = priority ?? DefaultCachePriority
+                });
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Generic method to get data from cache or execute a synchronous factory function if not cached
+        /// </summary>
+        /// <typeparam name="T">Type of data to cache</typeparam>
+        /// <param name="cacheKey">Unique cache key</param>
+        /// <param name="factory">Function to execute if data is not in cache</param>
+        /// <param name="expiration">Cache expiration time (optional, uses default if not provided)</param>
+        /// <param name="priority">Cache priority (optional, uses default if not provided)</param>
+        /// <returns>Cached or freshly retrieved data</returns>
+        protected T? GetOrSetCache<T>(
+            string cacheKey,
+            Func<T?> factory,
+            TimeSpan? expiration = null,
+            CacheItemPriority? priority = null) where T : class
+        {
+            // If caching is not available, execute factory directly
+            if (_cache == null)
+            {
+                return factory();
+            }
+
+            // Try to get cached data first
+            if (_cache.TryGetValue(cacheKey, out T? cachedData) && cachedData != null)
+            {
+                return cachedData;
+            }
+
+            // If not in cache, execute factory function
+            var result = factory();
+            
+            // Only cache non-null results
+            if (result != null)
+            {
+                _cache.Set(cacheKey, result, new MemoryCacheEntryOptions
+                {
+                    SlidingExpiration = expiration ?? DefaultCacheExpiration,
+                    Priority = priority ?? DefaultCachePriority
+                });
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Removes an item from cache by key
+        /// </summary>
+        /// <param name="cacheKey">Cache key to remove</param>
+        protected void ClearCache(string cacheKey)
+        {
+            _cache?.Remove(cacheKey);
+        }
+
+        /// <summary>
+        /// Checks if an item exists in cache
+        /// </summary>
+        /// <param name="cacheKey">Cache key to check</param>
+        /// <returns>True if item exists in cache, false otherwise</returns>
+        protected bool IsCached(string cacheKey)
+        {
+            return _cache?.TryGetValue(cacheKey, out _) ?? false;
+        }        /// <summary>
+        /// Generates a standardized cache key for entity-based caching
+        /// </summary>
+        /// <param name="entityName">Name of the entity (e.g., "Candidato", "Stats")</param>
+        /// <param name="identifier">Unique identifier for the entity (optional)</param>
+        /// <returns>Formatted cache key</returns>
+        protected static string GenerateCacheKey(string entityName, object? identifier = null)
+        {
+            return identifier != null ? $"{entityName}_{identifier}" : entityName;
         }
     }
 }

OpenCand.API/Repository/BemCandidatoRepository.cs

@@ -1,4 +1,5 @@
 using Dapper;
+using Microsoft.Extensions.Caching.Memory;
 using Npgsql;
 using OpenCand.Core.Models;
 
@@ -6,7 +7,7 @@ namespace OpenCand.Repository
 {
     public class BemCandidatoRepository : BaseRepository
     {
-        public BemCandidatoRepository(IConfiguration configuration) : base(configuration)
+        public BemCandidatoRepository(IConfiguration configuration, IMemoryCache? cache = null) : base(configuration, cache)
         {
         }
 

OpenCand.API/Repository/CandidatoRepository.cs

@@ -1,4 +1,5 @@
 using Dapper;
+using Microsoft.Extensions.Caching.Memory;
 using Npgsql;
 using OpenCand.Core.Models;
 
@@ -6,11 +7,15 @@ namespace OpenCand.Repository
 {
     public class CandidatoRepository : BaseRepository
     {
-        public CandidatoRepository(IConfiguration configuration) : base(configuration)
+        public CandidatoRepository(IConfiguration configuration, IMemoryCache? cache = null) : base(configuration, cache)
         {
         }
 
-        public async Task<List<Candidato>> SearchCandidatosAsync(string query)
+        public async Task<List<Candidato>?> SearchCandidatosAsync(string query)
+        {
+            string cacheKey = GenerateCacheKey("Search", query);
+
+            return await GetOrSetCacheAsync(cacheKey, async () =>
             {
                 using var connection = new NpgsqlConnection(ConnectionString);
                 return (await connection.QueryAsync<Candidato>(@"
@@ -22,9 +27,15 @@ namespace OpenCand.Repository
                     ORDER BY c.popularidade DESC, sim DESC, length(c.nome) ASC
                     LIMIT 10;
                 ", new { q = query })).AsList();
+            });
+            
         }
 
         public async Task<Candidato?> GetCandidatoAsync(Guid idcandidato)
+        {
+            string cacheKey = GenerateCacheKey("Candidato", idcandidato);
+            
+            return await GetOrSetCacheAsync(cacheKey, async () =>
             {
                 using (var connection = new NpgsqlConnection(ConnectionString))
                 {
@@ -33,6 +44,7 @@ namespace OpenCand.Repository
                         WHERE idcandidato = @idcandidato;",
                         new { idcandidato });
                 }
+            });
         }
 
         public async Task<string?> GetCandidatoCpfAsync(Guid idcandidato)

OpenCand.API/Repository/DespesaReceitaRepository.cs

@@ -1,4 +1,5 @@
 using Dapper;
+using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Configuration;
 using Npgsql;
 using OpenCand.Core.Models;
@@ -7,7 +8,7 @@ namespace OpenCand.Repository
 {
     public class DespesaReceitaRepository : BaseRepository
     {
-        public DespesaReceitaRepository(IConfiguration configuration) : base(configuration)
+        public DespesaReceitaRepository(IConfiguration configuration, IMemoryCache? cache = null) : base(configuration, cache)
         {
         }
 

OpenCand.API/Repository/OpenCandRepository.cs

@@ -1,17 +1,21 @@
 using Dapper;
+using Microsoft.Extensions.Caching.Memory;
 using Npgsql;
 using OpenCand.Core.Models;
 using OpenCand.Repository;
 
 namespace OpenCand.API.Repository
+{    public class OpenCandRepository : BaseRepository
     {
-    public class OpenCandRepository : BaseRepository
+        public OpenCandRepository(IConfiguration configuration, IMemoryCache? cache = null) : base(configuration, cache)
-    {
-        public OpenCandRepository(IConfiguration configuration) : base(configuration)
         {
         }
 
         public async Task<OpenCandStats> GetOpenCandStatsAsync()
+        {
+            string cacheKey = GenerateCacheKey("OpenCandStats");
+            
+            var result = await GetOrSetCacheAsync(cacheKey, async () =>
             {
                 using (var connection = new NpgsqlConnection(ConnectionString))
                 {
@@ -22,8 +26,20 @@ namespace OpenCand.API.Repository
                             (SELECT SUM(valor) FROM bem_candidato) AS TotalValorBemCandidatos,
                             (SELECT COUNT(*) FROM rede_social) AS TotalRedesSociais,
                             (SELECT COUNT(DISTINCT ano) FROM candidato_mapping) AS TotalEleicoes;");
+                    
                     return stats ?? new OpenCandStats();
                 }
+            });
+            
+            return result ?? new OpenCandStats();
+        }
+
+        /// <summary>
+        /// Clears the cached OpenCand statistics, forcing a fresh fetch on the next call
+        /// </summary>
+        public void ClearStatsCache()
+        {
+            ClearCache(GenerateCacheKey("OpenCandStats"));
         }
     }
 }