增加ImageCache微信 图片缓存

Modules/Store.ImageCache/Services/ImageCacheService.cs

@@ -0,0 +1,172 @@
+using MAX.Core.DependencyInjection;
+using Microsoft.Extensions.DependencyInjection;
+using Store.ImageCache.Dtos;
+using Store.ImageCache.Entities;
+using Store.ImageCache.Mapper;
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Store.ImageCache.Services
+{
+	public class ImageCacheService : ISingletonDependency
+	{
+		private const int Md5Length = 32;
+		private const int PlatformUrlMaxLength = 1000;
+
+		private readonly IFreeSql _freeSql;
+		private ImageCacheMapper mapper;
+		public ImageCacheService([FromKeyedServices("ImageCacheConnection")] IFreeSql freeSql)
+		{
+			mapper = new ImageCacheMapper();
+			if (freeSql == null)
+			{
+				throw new ArgumentNullException("freeSql");
+			}
+
+			_freeSql = freeSql;
+		}
+
+		/// <summary>
+		/// 按 MD5 查询图片缓存；platform 为空时返回该 MD5 在所有平台的缓存。
+		/// </summary>
+		public ImageCacheDto GetByMd5(string sourceUrlMd5, byte? platform = null)
+		{
+			var md5 = NormalizeMd5(sourceUrlMd5);
+			return GetByMd5sInternal(new List<string> { md5 }, platform).FirstOrDefault();
+		}
+
+		/// <summary>
+		/// 批量按 MD5 查询图片缓存。MD5 会按首字符分组，只查询对应的 images_0 到 images_f 分表。
+		/// </summary>
+		public List<ImageCacheDto> GetByMd5s(IEnumerable<string> sourceUrlMd5s, byte? platform = null)
+		{
+			return GetByMd5sInternal(NormalizeMd5s(sourceUrlMd5s), platform);
+		}
+
+
+
+		/// <summary>
+		/// 按 MD5 和平台直接修改平台图片 URL，未找到时返回 false。
+		/// </summary>
+		public bool AddOrUpdate(string sourceUrlMd5, byte platform, string platformUrl)
+		{
+			var md5 = NormalizeMd5(sourceUrlMd5);
+			ValidatePlatformUrl(platformUrl);
+			var tableName = GetTableName(md5[0]);
+			var existing = _freeSql.Select<ImageCacheEntity>()
+				.AsTable((type, oldName) => tableName)
+				.Where(a => a.source_url_md5 == sourceUrlMd5 && a.platform == platform)
+				.First();
+
+			var now = DateTime.Now;
+			if (existing != null)
+			{
+				var affected = _freeSql.Update<ImageCacheEntity>()
+				.AsTable(tableName)
+				.Set(a => a.platform_url, platformUrl)
+				.Set(a => a.update_time, now)
+				.Where(a => a.source_url_md5 == md5 && a.platform == platform)
+				.ExecuteAffrows();
+				return affected > 0;
+			}
+			else
+			{
+				ImageCacheEntity imageCache = new ImageCacheEntity();
+				imageCache.id = 0;
+				imageCache.source_url_md5 = md5;
+				imageCache.platform = platform;
+				imageCache.platform_url = platformUrl;
+				imageCache.create_time = now;
+				imageCache.update_time = now;
+				imageCache.id = _freeSql.Insert(imageCache)
+					.AsTable(tableName)
+					.ExecuteIdentity();
+				return imageCache.id > 0;
+			}
+		}
+
+		private List<ImageCacheDto> GetByMd5sInternal(List<string> md5s, byte? platform)
+		{
+			var result = new List<ImageCacheDto>();
+			if (md5s.Count == 0)
+			{
+				return result;
+			}
+
+			foreach (var shard in md5s.GroupBy(a => a[0]))
+			{
+				var tableName = GetTableName(shard.Key);
+				var md5sInTable = shard.ToList();
+				var query = _freeSql.Select<ImageCacheEntity>()
+					.AsTable((type, oldName) => tableName)
+					.Where(a => md5sInTable.Contains(a.source_url_md5));
+
+				if (platform.HasValue)
+				{
+					var platformValue = platform.Value;
+					query = query.Where(a => a.platform == platformValue);
+				}
+				result.AddRange(query.ToList().Select(mapper.ToDto));
+			}
+
+			return result;
+		}
+
+		private List<string> NormalizeMd5s(IEnumerable<string> sourceUrlMd5s)
+		{
+			if (sourceUrlMd5s == null)
+			{
+				throw new ArgumentNullException("sourceUrlMd5s");
+			}
+
+			var result = new List<string>();
+			foreach (var sourceUrlMd5 in sourceUrlMd5s)
+			{
+				var md5 = NormalizeMd5(sourceUrlMd5);
+				if (!result.Contains(md5))
+				{
+					result.Add(md5);
+				}
+			}
+
+			return result;
+		}
+
+		private string NormalizeMd5(string sourceUrlMd5)
+		{
+			if (string.IsNullOrWhiteSpace(sourceUrlMd5))
+			{
+				throw new ArgumentException("MD5 不能为空", "sourceUrlMd5");
+			}
+
+			var md5 = sourceUrlMd5.Trim().ToLowerInvariant();
+			if (md5.Length != Md5Length || md5.Any(a => !Uri.IsHexDigit(a)))
+			{
+				throw new ArgumentException("MD5 必须是 32 位十六进制字符串", "sourceUrlMd5");
+			}
+
+			return md5;
+		}
+
+		private string GetTableName(char shard)
+		{
+			return "images_" + shard;
+		}
+
+
+
+		private void ValidatePlatformUrl(string platformUrl)
+		{
+			if (string.IsNullOrWhiteSpace(platformUrl))
+			{
+				throw new ArgumentException("平台图片 URL 不能为空", "platformUrl");
+			}
+
+			if (platformUrl.Length > PlatformUrlMaxLength)
+			{
+				throw new ArgumentException("平台图片 URL 长度不能超过 1000", "platformUrl");
+			}
+		}
+	}
+}