src/main/java/com/imyeyu/api/modules/common/bean/attachment/Metadata.java

@@ -1,48 +0,0 @@
-package com.imyeyu.api.modules.common.bean.attachment;
-
-import lombok.Data;
-import lombok.EqualsAndHashCode;
-
-/**
- * @author 夜雨
- * @since 2025-12-11 18:14
- */
-public class Metadata {
-
-	/**
-	 * 图片
-	 *
-	 * @author 夜雨
-	 * @since 2025-12-11 18:15
-	 */
-	@Data
-	public static class Image {
-
-		private int width;
-
-		private int height;
-	}
-
-	/**
-	 * 缩略图
-	 *
-	 * @author 夜雨
-	 * @since 2026-01-04 18:10
-	 */
-	@Data
-	@EqualsAndHashCode(callSuper = true)
-	public static class ThumbImage extends Image {
-
-		private String sourceId;
-
-		private String sourceMongoId;
-
-		private String sourceMimeType;
-
-		/** 请求宽度（缓存键之一，null 表示未指定） */
-		private Integer requestWidth;
-
-		/** 请求高度（缓存键之一，null 表示未指定） */
-		private Integer requestHeight;
-	}
-}

src/main/java/com/imyeyu/api/modules/common/bean/attachment/ThumbnailFitMode.java

@@ -0,0 +1,17 @@
+package com.imyeyu.api.modules.common.bean.attachment;
+
+/// 缩略图缩放模式
+///
+/// @author 夜雨
+/// @since 2026-08-21
+public enum ThumbnailFitMode {
+
+	/// 保持比例完整放入目标尺寸
+	FIT,
+
+	/// 保持比例裁剪填满目标尺寸
+	COVER,
+
+	/// 强制缩放到目标尺寸，可能导致图片变形
+	STRETCH
+}

src/main/java/com/imyeyu/api/modules/common/controller/AttachmentController.java

@@ -1,7 +1,9 @@
 package com.imyeyu.api.modules.common.controller;
 
 import com.imyeyu.api.modules.common.entity.Attachment;
+import com.imyeyu.api.modules.common.bean.attachment.ThumbnailFitMode;
 import com.imyeyu.api.modules.common.service.AttachmentService;
+import com.imyeyu.api.modules.common.service.AttachmentVariantService;
 import com.imyeyu.api.modules.common.service.TempFileService;
 import com.imyeyu.api.modules.common.vo.attach.TempFileResp;
 import com.imyeyu.java.TimiJava;
@@ -41,6 +43,7 @@ public class AttachmentController {
 
 	private final TempFileService tempFileService;
 	private final AttachmentService service;
+	private final AttachmentVariantService variantService;
 
 	/**
 	 * 查询附件详情
@@ -184,14 +187,19 @@ public class AttachmentController {
 	@AOPLog
 	@IgnoreGlobalReturn
 	@GetMapping({"/read/{id}", "/download/{id}"})
-	public void readById(@PathVariable String id, @RequestParam(required = false) Integer thumbWidth, @RequestParam(required = false) Integer thumbHeight) throws UnsupportedEncodingException {
+	public void readById(
+		@PathVariable String id,
+		@RequestParam(required = false) Integer thumbWidth,
+		@RequestParam(required = false) Integer thumbHeight,
+		@RequestParam(defaultValue = "FIT") ThumbnailFitMode fitMode
+	) throws UnsupportedEncodingException {
 		HttpServletResponse resp = TimiSpring.getResponse();
 		Attachment attach = service.get(id);
 		if (attach == null) {
 			resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
 			return;
 		}
-		responseAttachment(attach, thumbWidth, thumbHeight);
+		responseAttachment(attach, thumbWidth, thumbHeight, fitMode);
 	}
 
 	@AOPLog
@@ -207,21 +215,31 @@ public class AttachmentController {
 	public void read(@RequestParam String id) throws UnsupportedEncodingException {
 		HttpServletResponse resp = TimiSpring.getResponse();
 		Attachment attach = service.get(id);
+		if (attach == null) {
+			resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
+			return;
+		}
 		if (TimiSpring.getRequest().getRequestURI().endsWith("/download")) {
 			resp.setHeader("Content-Disposition", Network.getFileDownloadHeader(attach.getName()));
 		}
-		response(attach);
+		response(attach, false);
 	}
 
-	private void responseAttachment(Attachment attach, Integer thumbWidth, Integer thumbHeight) throws UnsupportedEncodingException {
+	private void responseAttachment(
-		HttpServletResponse resp = TimiSpring.getResponse();
+		Attachment attach,
-		if (attach != null && TimiSpring.getRequest().getRequestURI().endsWith("/download") && attach.getName() != null) {
+		Integer thumbWidth,
-			resp.setHeader("Content-Disposition", Network.getFileDownloadHeader(attach.getName()));
+		Integer thumbHeight,
-		}
+		ThumbnailFitMode fitMode
-		responseThumb(attach, thumbWidth, thumbHeight);
+	) throws UnsupportedEncodingException {
+		responseThumb(attach, thumbWidth, thumbHeight, fitMode);
 	}
 
-	protected void responseThumb(Attachment attachment, Integer thumbWidth, Integer thumbHeight) {
+	protected void responseThumb(
+		Attachment attachment,
+		Integer thumbWidth,
+		Integer thumbHeight,
+		ThumbnailFitMode fitMode
+	) throws UnsupportedEncodingException {
 		HttpServletResponse resp = TimiSpring.getResponse();
 		if (TimiJava.isEmpty(attachment)) {
 			resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
@@ -229,21 +247,65 @@ public class AttachmentController {
 		}
 		if (thumbWidth == null && thumbHeight == null) {
 			// 原图
+			setDownloadHeader(attachment);
 			response(attachment);
 			return;
 		}
 		// 缩略图
-		Attachment thumb = service.fetchThumb(attachment, thumbWidth, thumbHeight);
+		Attachment thumb = variantService.fetchThumb(attachment, thumbWidth, thumbHeight, fitMode);
-		response(TimiJava.defaultIfNull(thumb, attachment));
+		setDownloadHeader(thumb);
+		response(thumb);
+	}
+
+	private void setDownloadHeader(Attachment attachment) throws UnsupportedEncodingException {
+		if (attachment != null && TimiSpring.getRequest().getRequestURI().endsWith("/download") && attachment.getName() != null) {
+			TimiSpring.getResponse().setHeader("Content-Disposition", Network.getFileDownloadHeader(attachment.getName()));
+		}
+	}
+
+	/// 设置附件缓存头并处理条件请求
+	///
+	/// @param attachment 实际响应附件
+	/// @return true 表示客户端缓存仍有效，已返回 304
+	private boolean responseCache(Attachment attachment) {
+		HttpServletResponse resp = TimiSpring.getResponse();
+		resp.setHeader("Cache-Control", "private, no-cache");
+		String md5 = attachment.getMd5();
+		if (md5 == null || md5.isBlank()) {
+			return false;
+		}
+		String etag = "\"%s\"".formatted(md5);
+		resp.setHeader("ETag", etag);
+		String ifNoneMatch = TimiSpring.getHeader("If-None-Match");
+		if (ifNoneMatch == null) {
+			return false;
+		}
+		for (String value : ifNoneMatch.split(",")) {
+			String candidate = value.trim();
+			if ("*".equals(candidate) || etag.equals(candidate) || ("W/" + etag).equals(candidate)) {
+				resp.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
+				return true;
+			}
+		}
+		return false;
 	}
 
 	protected void response(Attachment attachment) {
+		response(attachment, true);
+	}
+
+	private void response(Attachment attachment, boolean cacheable) {
 		HttpServletResponse resp = TimiSpring.getResponse();
 		try {
 			if (TimiJava.isEmpty(attachment)) {
 				resp.setStatus(HttpServletResponse.SC_NOT_FOUND);
 				return;
 			}
+			if (!cacheable) {
+				resp.setHeader("Cache-Control", "private, no-store");
+			} else if (responseCache(attachment)) {
+				return;
+			}
 			resp.setContentType(attachment.getMimeType());
 			attachment.doResponse();
 		} catch (Exception e) {

src/main/java/com/imyeyu/api/modules/common/entity/AttachmentVariant.java

@@ -0,0 +1,68 @@
+package com.imyeyu.api.modules.common.entity;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.imyeyu.api.modules.common.bean.attachment.ThumbnailFitMode;
+import com.imyeyu.spring.annotation.table.AutoUUID;
+import com.imyeyu.spring.annotation.table.Id;
+import lombok.Data;
+
+/// 附件缩略图变体记录
+///
+/// @author 夜雨
+/// @since 2026-08-21
+@Data
+public class AttachmentVariant {
+
+	/// 变体 ID
+	@Id
+	@AutoUUID
+	private String id;
+
+	/// 源附件 ID
+	private String sourceAttachmentId;
+
+	/// 源文件版本，使用源 GridFS ID
+	private String sourceMongoId;
+
+	/// 源文件摘要
+	private String sourceMd5;
+
+	/// 请求宽度，0 表示未指定
+	private int requestWidth;
+
+	/// 请求高度，0 表示未指定
+	private int requestHeight;
+
+	/// 缩放模式
+	private ThumbnailFitMode fitMode;
+
+	/// 输出格式
+	private String outputFormat;
+
+	/// 缩略图算法版本
+	private String algorithmVersion;
+
+	/// 缩略图 GridFS ID
+	private String mongoId;
+
+	/// 缩略图名称
+	private String name;
+
+	/// 缩略图 MIME 类型
+	private String mimeType;
+
+	/// 缩略图元数据
+	private ObjectNode metadata;
+
+	/// 缩略图大小
+	private long size;
+
+	/// 缩略图摘要
+	private String md5;
+
+	/// 创建时间
+	private long createdAt;
+
+	/// 过期时间
+	private long expireAt;
+}

src/main/java/com/imyeyu/api/modules/common/mapper/AttachmentMapper.java

@@ -36,26 +36,6 @@ public interface AttachmentMapper extends BaseMapper<Attachment, String>, RawMap
 
 	long countByBizId(Attachment.BizType bizType, String bizId, List<String> attachTypes);
 
-	/**
-	 * 按源附件 ID 与请求尺寸查询已缓存缩略图
-	 *
-	 * @param bizType       源附件业务类型
-	 * @param sourceId      源附件 ID
-	 * @param requestWidth  请求宽度，{@code null} 表示未指定
-	 * @param requestHeight 请求高度，{@code null} 表示未指定
-	 * @return 缩略图附件，不存在返回 {@code null}
-	 */
-	Attachment selectThumb(Attachment.BizType bizType, String sourceId, Integer requestWidth, Integer requestHeight);
-
-	/**
-	 * 查询源附件的所有未销毁缩略图（含已软删除）
-	 *
-	 * @param sourceId 源附件 ID
-	 * @return 缩略图列表
-	 */
-	@Select("SELECT * FROM attachment WHERE biz_id = #{sourceId} AND attach_type = 'THUMB' AND is_destroyed = FALSE")
-	List<Attachment> selectThumbsBySourceId(String sourceId);
-
 	@Select("SELECT * FROM attachment WHERE `is_destroyed` = FALSE AND `destroy_at` < " + UNIX_TIME)
 	List<Attachment> selectNeedDestroy();
 }

src/main/java/com/imyeyu/api/modules/common/mapper/AttachmentVariantMapper.java

@@ -0,0 +1,78 @@
+package com.imyeyu.api.modules.common.mapper;
+
+import com.imyeyu.api.modules.common.entity.Attachment;
+import com.imyeyu.api.modules.common.entity.AttachmentVariant;
+import org.apache.ibatis.annotations.Param;
+
+import java.util.List;
+
+/// 附件缩略图变体 Mapper
+///
+/// @author 夜雨
+/// @since 2026-08-21
+public interface AttachmentVariantMapper {
+
+	/// 查询有效缩略图附件
+	///
+	/// @param sourceAttachmentId 源附件 ID
+	/// @param sourceMongoId      源 GridFS ID
+	/// @param requestWidth       请求宽度，0 表示未指定
+	/// @param requestHeight      请求高度，0 表示未指定
+	/// @param fitMode            缩放模式
+	/// @param outputFormat       输出格式
+	/// @param algorithmVersion   算法版本
+	/// @param now                当前时间
+	/// @return 缩略图附件
+	Attachment selectValidAttachment(
+		@Param("sourceAttachmentId") String sourceAttachmentId,
+		@Param("sourceMongoId") String sourceMongoId,
+		@Param("requestWidth") int requestWidth,
+		@Param("requestHeight") int requestHeight,
+		@Param("fitMode") String fitMode,
+		@Param("outputFormat") String outputFormat,
+		@Param("algorithmVersion") String algorithmVersion,
+		@Param("now") long now
+	);
+
+	/// 查询指定变体记录，不判断是否过期
+	///
+	/// @param sourceAttachmentId 源附件 ID
+	/// @param sourceMongoId      源 GridFS ID
+	/// @param requestWidth       请求宽度，0 表示未指定
+	/// @param requestHeight      请求高度，0 表示未指定
+	/// @param fitMode            缩放模式
+	/// @param outputFormat       输出格式
+	/// @param algorithmVersion   算法版本
+	/// @return 变体记录
+	AttachmentVariant selectByKey(
+		@Param("sourceAttachmentId") String sourceAttachmentId,
+		@Param("sourceMongoId") String sourceMongoId,
+		@Param("requestWidth") int requestWidth,
+		@Param("requestHeight") int requestHeight,
+		@Param("fitMode") String fitMode,
+		@Param("outputFormat") String outputFormat,
+		@Param("algorithmVersion") String algorithmVersion
+	);
+
+	/// 查询源附件的所有变体
+	///
+	/// @param sourceAttachmentId 源附件 ID
+	/// @return 变体列表
+	List<AttachmentVariant> selectBySourceAttachmentId(@Param("sourceAttachmentId") String sourceAttachmentId);
+
+	/// 查询已过期变体
+	///
+	/// @param now 当前时间
+	/// @return 已过期变体列表
+	List<AttachmentVariant> selectExpired(@Param("now") long now);
+
+	/// 新增变体
+	///
+	/// @param variant 变体
+	void insert(AttachmentVariant variant);
+
+	/// 删除变体
+	///
+	/// @param id 变体 ID
+	void delete(@Param("id") String id);
+}

src/main/java/com/imyeyu/api/modules/common/service/AttachmentService.java

@@ -25,18 +25,6 @@ public interface AttachmentService extends BaseService<Attachment, String> {
 	/// @return 克隆后的附件
 	Attachment clone(String id);
 
-	/**
-	 * 按需获取或创建缩略图附件。
-	 * <p>当附件为图片或视频时，若指定尺寸的缩略图已存在则直接返回缓存，
-	 * 否则生成并持久化后返回。不支持缩略图的附件类型返回 {@code null}。</p>
-	 *
-	 * @param source        源附件（必须已持久化，mimeType 已填充）
-	 * @param requestWidth  请求宽度，{@code null} 表示未指定
-	 * @param requestHeight 请求高度，{@code null} 表示未指定
-	 * @return 缩略图附件，不支持时返回 {@code null}
-	 */
-	Attachment fetchThumb(Attachment source, Integer requestWidth, Integer requestHeight);
-
 	Attachment getByBizId(Attachment.BizType bizType, String bizId);
 
 	Attachment getByAttachType(Attachment.BizType bizType, String bizId, String attachType);

src/main/java/com/imyeyu/api/modules/common/service/AttachmentVariantService.java

@@ -0,0 +1,28 @@
+package com.imyeyu.api.modules.common.service;
+
+import com.imyeyu.api.modules.common.bean.attachment.ThumbnailFitMode;
+import com.imyeyu.api.modules.common.entity.Attachment;
+
+/// 附件缩略图变体服务
+///
+/// @author 夜雨
+/// @since 2026-08-21
+public interface AttachmentVariantService {
+
+	/// 按需获取或创建缩略图附件
+	///
+	/// @param source        源附件
+	/// @param requestWidth  请求宽度
+	/// @param requestHeight 请求高度
+	/// @param fitMode       缩放模式
+	/// @return 缩略图附件
+	Attachment fetchThumb(Attachment source, Integer requestWidth, Integer requestHeight, ThumbnailFitMode fitMode);
+
+	/// 删除源附件对应的全部缩略图变体
+	///
+	/// @param sourceAttachmentId 源附件 ID
+	void deleteBySourceId(String sourceAttachmentId);
+
+	/// 清理已过期的缩略图变体
+	void clearExpired();
+}

src/main/java/com/imyeyu/api/modules/common/service/implement/AttachmentServiceImplement.java

@@ -3,19 +3,14 @@ package com.imyeyu.api.modules.common.service.implement;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.imyeyu.api.config.dbsource.TimiServerDBConfig;
-import com.imyeyu.api.modules.common.bean.attachment.MediaAttach;
-import com.imyeyu.api.modules.common.bean.attachment.Metadata;
 import com.imyeyu.api.modules.common.entity.Attachment;
 import com.imyeyu.api.modules.common.mapper.AttachmentMapper;
 import com.imyeyu.api.modules.common.service.AttachmentService;
-import com.imyeyu.api.util.JavaCV;
+import com.imyeyu.api.modules.common.service.AttachmentVariantService;
 import com.imyeyu.io.IO;
 import com.imyeyu.java.TimiJava;
-import com.imyeyu.java.bean.CallbackArg;
 import com.imyeyu.java.bean.timi.TimiCode;
 import com.imyeyu.java.bean.timi.TimiException;
-import com.imyeyu.java.ref.Ref;
-import com.imyeyu.network.Network;
 import com.imyeyu.spring.TimiSpring;
 import com.imyeyu.spring.bean.Page;
 import com.imyeyu.spring.bean.PageResult;
@@ -26,7 +21,6 @@ import com.mongodb.client.gridfs.GridFSBucket;
 import com.mongodb.client.gridfs.model.GridFSFile;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import net.coobird.thumbnailator.Thumbnails;
 import org.apache.tika.Tika;
 import org.springframework.data.mongodb.core.query.Criteria;
 import org.springframework.data.mongodb.core.query.Query;
@@ -36,9 +30,6 @@ import org.springframework.transaction.annotation.Transactional;
 
 import javax.imageio.ImageIO;
 import java.awt.image.BufferedImage;
-import java.io.ByteArrayInputStream;
-import java.io.ByteArrayOutputStream;
-import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.ArrayList;
@@ -47,7 +38,6 @@ import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import java.util.Set;
-import java.util.UUID;
 import java.util.stream.Collectors;
 
 /**
@@ -64,6 +54,7 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 	private final ObjectMapper jackson;
 	private final GridFSBucket gridFSBucket;
 	private final GridFsTemplate gridFsTemplate;
+	private final AttachmentVariantService variantService;
 
 	@Override
 	protected BaseMapper<Attachment, String> mapper() {
@@ -124,6 +115,7 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 			}
 			// 有新文件时，先查旧记录获取旧 mongoId 和兜底字段
 			Attachment old = mapper.selectRaw(attachment.getId());
+			TimiException.required(old, "not found attachment");
 			// 存储新文件
 			newMongoId = gridFsTemplate.store(stream, attachment.buildMongoName()).toString();
 			GridFSFile gridFSFile = gridFsTemplate.findOne(new Query(Criteria.where("_id").is(newMongoId)));
@@ -141,6 +133,8 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 
 			// 更新数据库后删除旧 GridFS 文件
 			super.update(attachment);
+			// 源文件版本已变化，旧缩略图全部失效
+			variantService.deleteBySourceId(attachment.getId());
 			gridFsTemplate.delete(Query.query(Criteria.where("_id").is(old.getMongoId())));
 		} catch (Exception e) {
 			// 新文件已上传但后续操作失败，清理新文件防止孤儿数据
@@ -155,36 +149,18 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 	@Transactional(TimiServerDBConfig.ROLLBACKER)
 	@Override
 	public void delete(String id) {
-		mapper.selectThumbsBySourceId(id).forEach(thumb -> super.delete(thumb.getId()));
+		variantService.deleteBySourceId(id);
 		super.delete(id);
 	}
 
 	@Transactional(TimiServerDBConfig.ROLLBACKER)
 	@Override
 	public void destroy(String id) {
-		CallbackArg<Attachment> doDestroy = attach -> {
+		variantService.deleteBySourceId(id);
-			try {
+		Attachment attachment = mapper.selectRaw(id);
-				if (attach.getMongoId() != null) {
+		if (attachment != null) {
-					gridFsTemplate.delete(Query.query(Criteria.where("_id").is(attach.getMongoId())));
+			destroyAttachment(attachment);
-				}
+		}
-				if (!attach.isDeleted()) {
-					attach.setDeletedAt(Time.now());
-				}
-				attach.setIsDestroyed(true);
-				attach.setDestroyAt(Time.now());
-				mapper.update(attach);
-
-				if (Ref.toType(MediaAttach.Type.class, attach.getAttachType()) == MediaAttach.Type.THUMB) {
-					// 缩略图记录物理删除
-					mapper.destroy(attach.getId());
-				}
-			} catch (Exception e) {
-				log.error("delete mongo file error, id={}", attach.getId(), e);
-				throw new TimiException(TimiCode.ERROR, "TODO delete mongo file error");
-			}
-		};
-		mapper.selectThumbsBySourceId(id).forEach(doDestroy::handler);
-		doDestroy.handler(mapper.selectRaw(id));
 	}
 
 	@Transactional(TimiServerDBConfig.ROLLBACKER)
@@ -216,74 +192,20 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 		}
 	}
 
-	@Transactional(TimiServerDBConfig.ROLLBACKER)
+	private void destroyAttachment(Attachment attachment) {
-	@Override
-	public Attachment fetchThumb(Attachment source, Integer requestWidth, Integer requestHeight) {
-		TimiException.requiredTrue(requestWidth != null || requestHeight != null, "required width or height");
-		String mimeType = source.getMimeType();
-		boolean isImage = mimeType != null && Set.of("image/png", "image/bmp", "image/jpeg").contains(mimeType);
-		boolean isVideo = mimeType != null && Set.of("video/mp4", "video/quicktime").contains(mimeType);
-		if (!isImage && !isVideo) {
-			return null;
-		}
-		Attachment cached = mapper.selectThumb(source.getBizType(), source.getId(), requestWidth, requestHeight);
-		if (cached != null) {
-			// 命中缓存直接返回
-			return cached;
-		}
 		try {
-			ByteArrayOutputStream thumbStream = new ByteArrayOutputStream();
+			if (attachment.getMongoId() != null) {
-			CallbackArg<InputStream> applyThumbSize = inputStream -> {
+				gridFsTemplate.delete(Query.query(Criteria.where("_id").is(attachment.getMongoId())));
-				try {
-					Thumbnails.Builder<? extends InputStream> builder = Thumbnails.of(inputStream);
-					if (requestWidth != null && requestHeight != null) {
-						builder.size(requestWidth, requestHeight).keepAspectRatio(false).toOutputStream(thumbStream);
-					} else if (requestWidth != null) {
-						builder.width(requestWidth).keepAspectRatio(true).toOutputStream(thumbStream);
-					} else {
-						builder.height(requestHeight).keepAspectRatio(true).toOutputStream(thumbStream);
-					}
-				} catch (IOException e) {
-					log.error("applyThumbSize error for fetchThumb", e);
-					throw new RuntimeException(e);
-				}
-			};
-			if (isImage) {
-				applyThumbSize.handler(source.openInputStream());
-			} else {
-				String name = source.getName();
-				File tempFile = IO.file("temp/%s_%s".formatted(UUID.randomUUID(), name));
-				try {
-					IO.toFile(tempFile, source.openInputStream());
-					ByteArrayOutputStream baos = JavaCV.captureThumbnail(IO.getInputStream(tempFile), 2);
-					applyThumbSize.handler(IO.toInputStream(baos));
-				} finally {
-					IO.destroy(tempFile);
-				}
 			}
-			Metadata.ThumbImage thumbMeta = new Metadata.ThumbImage();
+			if (!attachment.isDeleted()) {
-			thumbMeta.setSourceId(source.getId());
+				attachment.setDeletedAt(Time.now());
-			thumbMeta.setSourceMongoId(source.getMongoId());
+			}
-			thumbMeta.setSourceMimeType(mimeType);
+			attachment.setIsDestroyed(true);
-			thumbMeta.setRequestWidth(requestWidth);
+			attachment.setDestroyAt(Time.now());
-			thumbMeta.setRequestHeight(requestHeight);
+			mapper.update(attachment);
-
-			Attachment thumb = new Attachment();
-			thumb.setName(Network.simpleURIFileName(source.getName()) + ".png");
-			thumb.setBizType(source.getBizType());
-			thumb.setBizId(source.getId());
-			thumb.setAttachType(MediaAttach.Type.THUMB.toString());
-			thumb.setMetadata(jackson.valueToTree(thumbMeta));
-			thumb.setInputStream(new ByteArrayInputStream(thumbStream.toByteArray()));
-			// 缩略图 7 天后过期，额外 1 天宽限供后台任务销毁
-			long expireAt = Time.now() + 7 * Time.D;
-			thumb.setDeletedAt(expireAt);
-			thumb.setDestroyAt(expireAt + Time.D);
-			create(thumb);
-			return thumb;
 		} catch (Exception e) {
-			log.error("create thumbnail error", e);
+			log.error("delete mongo file error, id={}", attachment.getId(), e);
-			throw new TimiException(TimiCode.ERROR, "exception.attachment.create.error");
+			throw new TimiException(TimiCode.ERROR, "TODO delete mongo file error", e);
 		}
 	}
 
@@ -390,6 +312,8 @@ public class AttachmentServiceImplement extends AbstractEntityService<Attachment
 				// 将临时文件的 GridFS 存储转移至当前永久记录，废弃临时记录
 				Attachment current = mapper.selectRaw(item.getId());
 				Attachment tempFile = mapper.selectRaw(tempFileId);
+				// 源文件版本已变化，旧缩略图全部失效
+				variantService.deleteBySourceId(current.getId());
 				// 删除旧 GridFS 文件
 				gridFsTemplate.delete(Query.query(Criteria.where("_id").is(current.getMongoId())));
 				// 将存储信息从临时记录迁移到永久记录

src/main/java/com/imyeyu/api/modules/common/service/implement/AttachmentVariantServiceImplement.java

@@ -0,0 +1,339 @@
+package com.imyeyu.api.modules.common.service.implement;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.imyeyu.api.config.dbsource.TimiServerDBConfig;
+import com.imyeyu.api.modules.common.bean.attachment.MediaAttach;
+import com.imyeyu.api.modules.common.bean.attachment.ThumbnailFitMode;
+import com.imyeyu.api.modules.common.entity.Attachment;
+import com.imyeyu.api.modules.common.entity.AttachmentVariant;
+import com.imyeyu.api.modules.common.mapper.AttachmentVariantMapper;
+import com.imyeyu.api.modules.common.service.AttachmentVariantService;
+import com.imyeyu.api.util.JavaCV;
+import com.imyeyu.io.IO;
+import com.imyeyu.java.TimiJava;
+import com.imyeyu.java.bean.timi.TimiCode;
+import com.imyeyu.java.bean.timi.TimiException;
+import com.imyeyu.network.Network;
+import com.imyeyu.spring.util.Redis;
+import com.imyeyu.utils.Time;
+import com.mongodb.client.gridfs.GridFSBucket;
+import com.mongodb.client.gridfs.model.GridFSFile;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import net.coobird.thumbnailator.Thumbnails;
+import net.coobird.thumbnailator.geometry.Positions;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.dao.DuplicateKeyException;
+import org.springframework.data.mongodb.core.query.Criteria;
+import org.springframework.data.mongodb.core.query.Query;
+import org.springframework.data.mongodb.gridfs.GridFsTemplate;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import javax.imageio.ImageIO;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.util.Set;
+import java.util.UUID;
+
+/// 附件缩略图变体服务实现
+///
+/// 负责缩略图生成、变体缓存、并发控制和变体文件清理，源附件生命周期由 `AttachmentService` 负责
+///
+/// @author 夜雨
+/// @since 2026-08-21
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class AttachmentVariantServiceImplement implements AttachmentVariantService {
+
+	private static final int THUMB_MAX_WIDTH = 4096;
+	private static final int THUMB_MAX_HEIGHT = 4096;
+	private static final long THUMB_MAX_PIXELS = 16_000_000L;
+	private static final long THUMB_CACHE_TTL = Time.D * 7;
+	private static final long THUMB_LOCK_TTL = Time.M * 10;
+	private static final double THUMB_TARGET_SECONDS = 2;
+	private static final String THUMB_OUTPUT_FORMAT = "png";
+	private static final String THUMB_ALGORITHM_VERSION = "v3";
+	private static final String THUMB_LOCK_KEY_PREFIX = "ATTACHMENT:THUMB:LOCK:";
+
+	private final AttachmentVariantMapper variantMapper;
+	private final ObjectMapper jackson;
+	private final GridFSBucket gridFSBucket;
+	private final GridFsTemplate gridFsTemplate;
+
+	@Qualifier("redisLocker")
+	private final Redis<String, Integer> redisLocker;
+
+	@Override
+	public Attachment fetchThumb(Attachment source, Integer requestWidth, Integer requestHeight, ThumbnailFitMode fitMode) {
+		TimiException.required(source, "not found source attachment");
+		TimiException.required(source.getId(), "not found source attachment.id");
+		TimiException.required(source.getMongoId(), "not found source attachment.mongoId");
+		TimiException.requiredTrue(requestWidth != null || requestHeight != null, "required width or height");
+		if (requestWidth != null && !(0 < requestWidth && requestWidth < THUMB_MAX_WIDTH + 1)) {
+			throw new TimiException(TimiCode.ARG_BAD, "attachment.thumbnail.width.invalid");
+		}
+		if (requestHeight != null && !(0 < requestHeight && requestHeight < THUMB_MAX_HEIGHT + 1)) {
+			throw new TimiException(TimiCode.ARG_BAD, "attachment.thumbnail.height.invalid");
+		}
+		if (requestWidth != null && requestHeight != null) {
+			long pixels = (long) requestWidth * requestHeight;
+			if (THUMB_MAX_PIXELS < pixels) {
+				throw new TimiException(TimiCode.ARG_BAD, "attachment.thumbnail.area.invalid");
+			}
+		}
+		fitMode = TimiJava.defaultIfNull(fitMode, ThumbnailFitMode.FIT);
+
+		String mimeType = source.getMimeType();
+		boolean isImage = mimeType != null && Set.of("image/png", "image/bmp", "image/jpeg").contains(mimeType);
+		boolean isVideo = mimeType != null && Set.of("video/mp4", "video/quicktime").contains(mimeType);
+		if (!isImage && !isVideo) {
+			throw new TimiException(TimiCode.ARG_BAD, "attachment.thumbnail.not.support");
+		}
+
+		int width = TimiJava.defaultIfNull(requestWidth, 0);
+		int height = TimiJava.defaultIfNull(requestHeight, 0);
+		long now = Time.now();
+		Attachment cached = variantMapper.selectValidAttachment(
+			source.getId(),
+			source.getMongoId(),
+			width,
+			height,
+			fitMode.toString(),
+			THUMB_OUTPUT_FORMAT,
+			THUMB_ALGORITHM_VERSION,
+			now
+		);
+		if (cached != null) {
+			return cached;
+		}
+
+		String lockKey = buildThumbLockKey(source, width, height, fitMode);
+		if (!redisLocker.lock(lockKey, 1, THUMB_LOCK_TTL)) {
+			throw new TimiException(TimiCode.ERROR_SERVICE_BUSY, "attachment.thumbnail.generating");
+		}
+		try {
+			cached = variantMapper.selectValidAttachment(
+				source.getId(),
+				source.getMongoId(),
+				width,
+				height,
+				fitMode.toString(),
+				THUMB_OUTPUT_FORMAT,
+				THUMB_ALGORITHM_VERSION,
+				Time.now()
+			);
+			if (cached != null) {
+				return cached;
+			}
+			AttachmentVariant oldVariant = variantMapper.selectByKey(
+				source.getId(),
+				source.getMongoId(),
+				width,
+				height,
+				fitMode.toString(),
+				THUMB_OUTPUT_FORMAT,
+				THUMB_ALGORITHM_VERSION
+			);
+			if (oldVariant != null) {
+				deleteVariant(oldVariant);
+			}
+			File thumbFile = null;
+			AttachmentVariant variant = null;
+			boolean variantInserted = false;
+			try {
+				thumbFile = createThumbFile(source, requestWidth, requestHeight, fitMode, isImage);
+				variant = new AttachmentVariant();
+				variant.setId(UUID.randomUUID().toString());
+				variant.setName(Network.simpleURIFileName(source.getName()) + "." + THUMB_OUTPUT_FORMAT);
+				variant.setMimeType("image/" + THUMB_OUTPUT_FORMAT);
+				long expireAt = Time.now() + THUMB_CACHE_TTL;
+				variant.setSourceAttachmentId(source.getId());
+				variant.setSourceMongoId(source.getMongoId());
+				variant.setSourceMd5(source.getMd5());
+				variant.setRequestWidth(width);
+				variant.setRequestHeight(height);
+				variant.setFitMode(fitMode);
+				variant.setOutputFormat(THUMB_OUTPUT_FORMAT);
+				variant.setAlgorithmVersion(THUMB_ALGORITHM_VERSION);
+				variant.setCreatedAt(Time.now());
+				variant.setExpireAt(expireAt);
+				BufferedImage image = ImageIO.read(thumbFile);
+				if (image != null) {
+					ObjectNode metadata = jackson.createObjectNode();
+					metadata.put("width", image.getWidth());
+					metadata.put("height", image.getHeight());
+					variant.setMetadata(metadata);
+				}
+				try (InputStream inputStream = Files.newInputStream(thumbFile.toPath())) {
+					String mongoId = gridFsTemplate.store(inputStream, variant.getName()).toString();
+					GridFSFile gridFSFile = gridFsTemplate.findOne(new Query(Criteria.where("_id").is(mongoId)));
+					variant.setMongoId(mongoId);
+					variant.setSize(gridFSFile.getLength());
+					try (InputStream md5InputStream = gridFSBucket.openDownloadStream(gridFSFile.getObjectId())) {
+						variant.setMd5(IO.md5(md5InputStream));
+					}
+				}
+				try {
+					variantMapper.insert(variant);
+					variantInserted = true;
+				} catch (DuplicateKeyException e) {
+					destroyVariantFile(variant);
+					Attachment concurrent = variantMapper.selectValidAttachment(
+						source.getId(),
+						source.getMongoId(),
+						width,
+						height,
+						fitMode.toString(),
+						THUMB_OUTPUT_FORMAT,
+						THUMB_ALGORITHM_VERSION,
+						Time.now()
+					);
+					if (concurrent != null) {
+						return concurrent;
+					}
+					throw e;
+				}
+				return toThumbAttachment(source, variant);
+			} catch (Exception e) {
+				if (variant != null) {
+					destroyVariantFile(variant);
+					if (variantInserted) {
+						variantMapper.delete(variant.getId());
+					}
+				}
+				throw e;
+			} finally {
+				IO.destroy(thumbFile);
+			}
+		} catch (TimiException e) {
+			throw e;
+		} catch (Exception e) {
+			log.error("create thumbnail error", e);
+			throw new TimiException(TimiCode.ERROR, "exception.attachment.create.error", e);
+		} finally {
+			redisLocker.releaseLock(lockKey);
+		}
+	}
+
+	private String buildThumbLockKey(Attachment source, int width, int height, ThumbnailFitMode fitMode) {
+		return "%s%s:%s:%s:%s:%s".formatted(
+			THUMB_LOCK_KEY_PREFIX,
+			source.getId(),
+			source.getMongoId(),
+			width,
+			height,
+			fitMode
+		);
+	}
+
+	private File createThumbFile(
+		Attachment source,
+		Integer requestWidth,
+		Integer requestHeight,
+		ThumbnailFitMode fitMode,
+		boolean isImage
+	) throws Exception {
+		File thumbFile = Files.createTempFile("timi-thumb-", ".png").toFile();
+		try {
+			if (isImage) {
+				try (InputStream inputStream = source.openInputStream()) {
+					resize(inputStream, thumbFile, requestWidth, requestHeight, fitMode);
+				}
+				return thumbFile;
+			}
+
+			try (InputStream inputStream = source.openInputStream()) {
+				ByteArrayOutputStream frame = JavaCV.captureThumbnail(inputStream, THUMB_TARGET_SECONDS);
+				if (!(0 < frame.size())) {
+					throw new TimiException(TimiCode.ERROR_NOT_SUPPORT, "attachment.thumbnail.video.frame.empty");
+				}
+				try (InputStream frameInputStream = new ByteArrayInputStream(frame.toByteArray())) {
+					resize(frameInputStream, thumbFile, requestWidth, requestHeight, fitMode);
+				}
+				return thumbFile;
+			}
+		} catch (Exception e) {
+			IO.destroy(thumbFile);
+			throw e;
+		}
+	}
+
+	private void resize(
+		InputStream inputStream,
+		File outputFile,
+		Integer requestWidth,
+		Integer requestHeight,
+		ThumbnailFitMode fitMode
+	) throws IOException {
+		Thumbnails.Builder<? extends InputStream> builder = Thumbnails.of(inputStream)
+			.useExifOrientation(true)
+			.outputFormat(THUMB_OUTPUT_FORMAT);
+		if (requestWidth != null && requestHeight != null) {
+			switch (fitMode) {
+				case FIT -> builder.size(requestWidth, requestHeight).keepAspectRatio(true);
+				case COVER -> builder.size(requestWidth, requestHeight).keepAspectRatio(true).crop(Positions.CENTER);
+				case STRETCH -> builder.size(requestWidth, requestHeight).keepAspectRatio(false);
+			}
+		} else if (requestWidth != null) {
+			builder.width(requestWidth).keepAspectRatio(true);
+		} else {
+			builder.height(requestHeight).keepAspectRatio(true);
+		}
+		builder.toFile(outputFile);
+	}
+
+	@Transactional(TimiServerDBConfig.ROLLBACKER)
+	@Override
+	public void deleteBySourceId(String sourceAttachmentId) {
+		for (AttachmentVariant variant : variantMapper.selectBySourceAttachmentId(sourceAttachmentId)) {
+			deleteVariant(variant);
+		}
+	}
+
+	private void deleteVariant(AttachmentVariant variant) {
+		destroyVariantFile(variant);
+		variantMapper.delete(variant.getId());
+	}
+
+	private void destroyVariantFile(AttachmentVariant variant) {
+		if (variant.getMongoId() != null) {
+			gridFsTemplate.delete(Query.query(Criteria.where("_id").is(variant.getMongoId())));
+		}
+	}
+
+	private Attachment toThumbAttachment(Attachment source, AttachmentVariant variant) {
+		Attachment thumb = new Attachment();
+		thumb.setId(variant.getId());
+		thumb.setBizType(source.getBizType());
+		thumb.setBizId(source.getId());
+		thumb.setAttachType(MediaAttach.Type.THUMB.toString());
+		thumb.setMongoId(variant.getMongoId());
+		thumb.setName(variant.getName());
+		thumb.setMimeType(variant.getMimeType());
+		thumb.setMetadata(variant.getMetadata());
+		thumb.setSize(variant.getSize());
+		thumb.setMd5(variant.getMd5());
+		thumb.setIsDestroyed(false);
+		thumb.setDestroyAt(variant.getExpireAt());
+		return thumb;
+	}
+
+	@Override
+	public void clearExpired() {
+		for (AttachmentVariant variant : variantMapper.selectExpired(Time.now())) {
+			try {
+				deleteVariant(variant);
+			} catch (Exception e) {
+				log.error("clear expired thumbnail variant error, id={}", variant.getId(), e);
+			}
+		}
+	}
+}

src/main/java/com/imyeyu/api/modules/common/task/AttachmentClearTask.java

@@ -2,6 +2,7 @@ package com.imyeyu.api.modules.common.task;
 
 import com.imyeyu.api.modules.common.entity.Attachment;
 import com.imyeyu.api.modules.common.service.AttachmentService;
+import com.imyeyu.api.modules.common.service.AttachmentVariantService;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.context.annotation.Configuration;
@@ -23,6 +24,7 @@ import java.util.List;
 public class AttachmentClearTask {
 
 	private final AttachmentService attachmentService;
+	private final AttachmentVariantService attachmentVariantService;
 
 	@Scheduled(cron = "0 0 1 * * ?")
 	public void run() {
@@ -31,16 +33,17 @@ public class AttachmentClearTask {
 			List<Attachment> needDestroyList = attachmentService.listNeedDestroy();
 			if (needDestroyList.isEmpty()) {
 				log.info("nothing attachment need clear");
-				return;
+			} else {
-			}
+				for (Attachment attach : needDestroyList) {
-			for (Attachment attach : needDestroyList) {
+					try {
-				try {
+						attachmentService.destroy(attach.getId());
-					attachmentService.destroy(attach.getId());
+						log.info("clear attachment success: id[{}]", attach.getId());
-					log.info("clear attachment success: id[{}]", attach.getId());
+					} catch (Exception e) {
-				} catch (Exception e) {
+						log.error("clear attachment error: id[{}]", attach.getId(), e);
-					log.error("clear attachment error: id[{}]", attach.getId(), e);
+					}
 				}
 			}
+			attachmentVariantService.clearExpired();
 			log.info("end clear expired attachments");
 		} catch (Exception e) {
 			log.error("attachment clear task error", e);

src/main/java/com/imyeyu/api/util/JavaCV.java

@@ -7,36 +7,58 @@ import org.bytedeco.javacv.Java2DFrameConverter;
 import javax.imageio.ImageIO;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayOutputStream;
+import java.io.IOException;
 import java.io.InputStream;
 
-/**
+/// JavaCV 工具类
- *
+///
- *
+/// @author 夜雨
- * @author 夜雨
+/// @since 2025-10-23 17:05
- * @since 2025-10-23 17:05
- */
 public class JavaCV {
 
-    public static ByteArrayOutputStream captureThumbnail(InputStream stream, double targetSeconds) throws Exception {
+	/// 从视频流顺序解码并提取指定时间附近的一帧 PNG 图片
-        ByteArrayOutputStream outStream = new ByteArrayOutputStream();
+	///
-        try (FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(stream)) {
+	/// 不执行时间定位，避免为了取实时缩略图而把整个视频复制到临时文件
-            grabber.start();
+	///
-            long targetMillis = (long) (targetSeconds * 1000);
+	/// @param stream        视频输入流
-            grabber.setTimestamp(targetMillis);
+	/// @param targetSeconds 目标时间，单位为秒
-            Frame frame;
+	/// @return PNG 图片字节流
-            while ((frame = grabber.grabImage()) != null) {
+	/// @throws Exception 视频解析或取帧失败
-                if (grabber.getTimestamp() >= targetMillis) {
+	public static ByteArrayOutputStream captureThumbnail(InputStream stream, double targetSeconds) throws Exception {
-                    Java2DFrameConverter converter = new Java2DFrameConverter();
+		long targetMicros = toMicros(targetSeconds);
-                    try (converter) {
+		ByteArrayOutputStream firstFrame = new ByteArrayOutputStream();
-                        BufferedImage bi = converter.getBufferedImage(frame);
+		try (FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(stream)) {
-                        if (bi != null) {
+			grabber.start();
-                            ImageIO.write(bi, "png", outStream);
+			try (Java2DFrameConverter converter = new Java2DFrameConverter()) {
-                            break;
+				Frame frame;
-                        }
+				while ((frame = grabber.grabImage()) != null) {
-                    }
+					BufferedImage image = converter.getBufferedImage(frame);
-                }
+					if (image == null) {
-            }
+						continue;
-        }
+					}
-        return outStream;
+					if (!(0 < firstFrame.size())) {
-    }
+						firstFrame = toPng(image);
+					}
+					if (grabber.getTimestamp() >= targetMicros) {
+						return targetMicros == 0 ? firstFrame : toPng(image);
+					}
+				}
+			}
+		}
+		// 短视频提前结束时退回首个有效帧
+		return firstFrame;
+	}
+
+	private static long toMicros(double targetSeconds) {
+		double seconds = Double.isFinite(targetSeconds) ? Math.max(0, targetSeconds) : 0;
+		return Math.round(seconds * 1_000_000D);
+	}
+
+	private static ByteArrayOutputStream toPng(BufferedImage image) throws IOException {
+		ByteArrayOutputStream output = new ByteArrayOutputStream();
+		if (ImageIO.write(image, "png", output)) {
+			return output;
+		}
+		return new ByteArrayOutputStream();
+	}
 }

src/main/resources/db/migration/timiserver/V39__create_attachment_variant_table.sql

@@ -0,0 +1,32 @@
+CREATE TABLE `attachment_variant` (
+  `id` VARCHAR(36) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `source_attachment_id` VARCHAR(36) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `source_mongo_id` VARCHAR(24) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `source_md5` VARCHAR(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci,
+  `request_width` INT UNSIGNED NOT NULL DEFAULT 0,
+  `request_height` INT UNSIGNED NOT NULL DEFAULT 0,
+  `fit_mode` VARCHAR(16) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `output_format` VARCHAR(16) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `algorithm_version` VARCHAR(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `mongo_id` VARCHAR(24) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `name` VARCHAR(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci,
+  `mime_type` VARCHAR(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL,
+  `metadata` LONGTEXT CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci,
+  `size` BIGINT(20) NOT NULL,
+  `md5` VARCHAR(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci,
+  `created_at` BIGINT(20) NOT NULL,
+  `expire_at` BIGINT(20) NOT NULL,
+  PRIMARY KEY (`id`) USING BTREE,
+  UNIQUE INDEX `uk_source_variant`(
+    `source_attachment_id`,
+    `source_mongo_id`,
+    `request_width`,
+    `request_height`,
+    `fit_mode`,
+    `output_format`,
+    `algorithm_version`
+  ) USING BTREE,
+  UNIQUE INDEX `uk_mongo_id`(`mongo_id`) USING BTREE,
+  INDEX `idx_source_attachment_id`(`source_attachment_id`) USING BTREE,
+  INDEX `idx_expire_at`(`expire_at`) USING BTREE
+) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_unicode_ci COMMENT = '附件缩略图变体' ROW_FORMAT = Dynamic;

src/main/resources/mapper/timi-server/common/AttachmentMapper.xml

@@ -26,33 +26,4 @@
 			</if>
 		ORDER BY `created_at`
 	</select>
-	<select id="selectThumb" resultType="com.imyeyu.api.modules.common.entity.Attachment">
-		SELECT
-		    *
-		FROM
-		    `attachment`
-		WHERE
-		    biz_type = #{bizType}
-			AND biz_id = #{sourceId}
-			AND attach_type = 'THUMB'
-			<choose>
-				<when test="requestWidth != null">
-					AND JSON_EXTRACT(metadata, '$.requestWidth') = #{requestWidth}
-				</when>
-				<otherwise>
-					AND JSON_EXTRACT(metadata, '$.requestWidth') IS NULL
-				</otherwise>
-			</choose>
-			<choose>
-				<when test="requestHeight != null">
-					AND JSON_EXTRACT(metadata, '$.requestHeight') = #{requestHeight}
-				</when>
-				<otherwise>
-					AND JSON_EXTRACT(metadata, '$.requestHeight') IS NULL
-				</otherwise>
-			</choose>
-			AND is_destroyed = FALSE
-			AND UNIX_TIMESTAMP() * 1000 &lt; destroy_at
-		LIMIT 1
-	</select>
 </mapper>

src/main/resources/mapper/timi-server/common/AttachmentVariantMapper.xml

@@ -0,0 +1,105 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
+<mapper namespace="com.imyeyu.api.modules.common.mapper.AttachmentVariantMapper">
+	<sql id="variantKey">
+		`source_attachment_id` = #{sourceAttachmentId}
+		AND `source_mongo_id` = #{sourceMongoId}
+		AND `request_width` = #{requestWidth}
+		AND `request_height` = #{requestHeight}
+		AND `fit_mode` = #{fitMode}
+		AND `output_format` = #{outputFormat}
+		AND `algorithm_version` = #{algorithmVersion}
+	</sql>
+
+	<select id="selectValidAttachment" resultType="com.imyeyu.api.modules.common.entity.Attachment">
+		SELECT
+			v.`id`,
+			a.`biz_type`,
+			v.`source_attachment_id` AS `biz_id`,
+			'THUMB' AS `attach_type`,
+			v.`mongo_id`,
+			v.`name`,
+			v.`mime_type`,
+			v.`metadata`,
+			v.`size`,
+			v.`md5`,
+			FALSE AS `is_destroyed`,
+			v.`created_at`,
+			v.`expire_at` AS `destroy_at`
+		FROM `attachment_variant` v
+		INNER JOIN `attachment` a ON a.`id` = v.`source_attachment_id`
+		WHERE
+			<include refid="variantKey" />
+			AND v.`expire_at` &gt; #{now}
+			AND a.`mongo_id` = v.`source_mongo_id`
+			AND a.`is_destroyed` = FALSE
+			AND (a.`deleted_at` IS NULL OR #{now} &lt; a.`deleted_at`)
+			AND (a.`destroy_at` IS NULL OR #{now} &lt; a.`destroy_at`)
+		LIMIT 1
+	</select>
+
+	<select id="selectByKey" resultType="com.imyeyu.api.modules.common.entity.AttachmentVariant">
+		SELECT *
+		FROM `attachment_variant`
+		WHERE
+			<include refid="variantKey" />
+		LIMIT 1
+	</select>
+
+	<select id="selectBySourceAttachmentId" resultType="com.imyeyu.api.modules.common.entity.AttachmentVariant">
+		SELECT *
+		FROM `attachment_variant`
+		WHERE `source_attachment_id` = #{sourceAttachmentId}
+	</select>
+
+	<select id="selectExpired" resultType="com.imyeyu.api.modules.common.entity.AttachmentVariant">
+		SELECT *
+		FROM `attachment_variant`
+		WHERE `expire_at` &lt;= #{now}
+	</select>
+
+	<insert id="insert">
+		INSERT INTO `attachment_variant` (
+			`id`,
+			`source_attachment_id`,
+			`source_mongo_id`,
+			`source_md5`,
+			`request_width`,
+			`request_height`,
+			`fit_mode`,
+			`output_format`,
+			`algorithm_version`,
+			`mongo_id`,
+			`name`,
+			`mime_type`,
+			`metadata`,
+			`size`,
+			`md5`,
+			`created_at`,
+			`expire_at`
+		) VALUES (
+			#{id},
+			#{sourceAttachmentId},
+			#{sourceMongoId},
+			#{sourceMd5},
+			#{requestWidth},
+			#{requestHeight},
+			#{fitMode},
+			#{outputFormat},
+			#{algorithmVersion},
+			#{mongoId},
+			#{name},
+			#{mimeType},
+			#{metadata},
+			#{size},
+			#{md5},
+			#{createdAt},
+			#{expireAt}
+		)
+	</insert>
+
+	<delete id="delete">
+		DELETE FROM `attachment_variant`
+		WHERE `id` = #{id}
+	</delete>
+</mapper>