diff --git a/ruoyi-admin/src/main/resources/application.yml b/ruoyi-admin/src/main/resources/application.yml
index ac4b9da..ae60083 100644
--- a/ruoyi-admin/src/main/resources/application.yml
+++ b/ruoyi-admin/src/main/resources/application.yml
@@ -139,6 +139,7 @@ tenant:
     - sys_user_post
     - sys_user_role
     - sys_client
+    - sys_oss
     - sys_oss_config
     - sys_oss_resource
     - sys_oss_textbook
diff --git a/ruoyi-common/ruoyi-common-core/src/main/java/org/dromara/common/core/constant/CacheNames.java b/ruoyi-common/ruoyi-common-core/src/main/java/org/dromara/common/core/constant/CacheNames.java
index 08c5fe8..fe6f0c7 100644
--- a/ruoyi-common/ruoyi-common-core/src/main/java/org/dromara/common/core/constant/CacheNames.java
+++ b/ruoyi-common/ruoyi-common-core/src/main/java/org/dromara/common/core/constant/CacheNames.java
@@ -64,6 +64,7 @@ public interface CacheNames {
      * OSS内容
      */
     String SYS_OSS = "sys_oss#30d";
+    String SYS_OSS_IDENTIFIER = "sys_oss_identifier#30d";
 
     /**
      * OSS配置
diff --git a/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/controller/FileController.java b/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/controller/FileController.java
index 1898250..827e661 100644
--- a/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/controller/FileController.java
+++ b/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/controller/FileController.java
@@ -4,8 +4,8 @@ import jakarta.servlet.http.HttpServletResponse;
 import lombok.RequiredArgsConstructor;
 import org.dromara.file.service.IFileService;
 import org.springframework.validation.annotation.Validated;
-import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RestController;
 
@@ -32,7 +32,7 @@ public class FileController {
      * @param ossId OSS对象ID
      */
     //@SaCheckPermission("system:oss:download")
-    @GetMapping("/preview/{ossId}")
+    @PostMapping("/preview/{ossId}")
     public void preview(@PathVariable Long ossId, HttpServletResponse response) throws Exception {
         fileService.preview(ossId, response);
     }
diff --git a/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/domain/bo/OssFileBo.java b/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/domain/bo/OssFileBo.java
new file mode 100644
index 0000000..7347d2b
--- /dev/null
+++ b/ruoyi-modules/ruoyi-file/src/main/java/org/dromara/file/domain/bo/OssFileBo.java
@@ -0,0 +1,35 @@
+package org.dromara.file.domain.bo;
+
+import io.github.linpeilie.annotations.AutoMapper;
+import io.github.linpeilie.annotations.AutoMappers;
+import org.dromara.file.domain.SysOssResource;
+import org.dromara.file.domain.SysOssTextbook;
+
+/**
+ * <p>TODO<p>
+ *
+ * @author cjw
+ * @version V1.0.0
+ * @date 2024/6/3 16:45
+ */
+@AutoMappers({
+    @AutoMapper(target = SysOssResource.class, reverseConvertGenerate = false),
+    @AutoMapper(target = SysOssTextbook.class, reverseConvertGenerate = false)
+})
+public class OssFileBo {
+
+    /**
+     *
+     */
+    private Long ossId;
+
+    /**
+     *
+     */
+    private Long catalogId;
+
+    /**
+     * 1课件，2课堂，3作业，4试卷
+     */
+    private Integer type;
+}
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/controller/system/SysOssController.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/controller/system/SysOssController.java
index 73ada3b..b17a516 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/controller/system/SysOssController.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/controller/system/SysOssController.java
@@ -105,4 +105,16 @@ public class SysOssController extends BaseController {
         return toAjax(ossService.deleteWithValidByIds(List.of(ossIds), true));
     }
 
+    /**
+     * 查询OSS对象基于md5
+     *
+     * @param md5 OSS对象md5
+     */
+    @SaCheckPermission("system:oss:identifier")
+    @GetMapping("/identifier")
+    public R<Long> identifier(@NotEmpty(message = "MD5不能为空") String md5) {
+        Long ossId = ossService.getIdByMd5(md5);
+        return R.ok(ossId);
+    }
+
 }
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/SysOss.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/SysOss.java
index af88898..027f3ed 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/SysOss.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/SysOss.java
@@ -2,9 +2,9 @@ package org.dromara.system.domain;
 
 import com.baomidou.mybatisplus.annotation.TableId;
 import com.baomidou.mybatisplus.annotation.TableName;
-import org.dromara.common.tenant.core.TenantEntity;
 import lombok.Data;
 import lombok.EqualsAndHashCode;
+import org.dromara.common.mybatis.core.domain.BaseEntity;
 
 /**
  * OSS对象存储对象
@@ -14,7 +14,7 @@ import lombok.EqualsAndHashCode;
 @Data
 @EqualsAndHashCode(callSuper = true)
 @TableName("sys_oss")
-public class SysOss extends TenantEntity {
+public class SysOss extends BaseEntity {
 
     /**
      * 对象存储主键
@@ -27,6 +27,11 @@ public class SysOss extends TenantEntity {
      */
     private String fileName;
 
+    /**
+     * md5
+     */
+    private String fileMd5;
+
     /**
      * 原名
      */
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/bo/SysOssBo.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/bo/SysOssBo.java
index 7cb3104..175c3b3 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/bo/SysOssBo.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/domain/bo/SysOssBo.java
@@ -26,6 +26,11 @@ public class SysOssBo extends BaseEntity {
      */
     private String fileName;
 
+    /**
+     * md5
+     */
+    private String fileMd5;
+
     /**
      * 原名
      */
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/ISysOssService.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/ISysOssService.java
index bb37ca3..aab7097 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/ISysOssService.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/ISysOssService.java
@@ -78,5 +78,14 @@ public interface ISysOssService {
     Boolean deleteWithValidByIds(Collection<Long> ids, Boolean isValid);
 
 
+    /**
+     * 根据 md5 从缓存或数据库中获取 SysOssVo 对象
+     *
+     * @param md5 文件在数据库中的唯一标识
+     * @return SysOssVo 对象，包含文件信息
+     */
+    Long getIdByMd5(String md5);
+
+
 
 }
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysDeptServiceImpl.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysDeptServiceImpl.java
index 18cf1f4..edc067e 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysDeptServiceImpl.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysDeptServiceImpl.java
@@ -291,7 +291,7 @@ public class SysDeptServiceImpl implements ISysDeptService, DeptService {
 
     @Caching(evict = {
         @CacheEvict(cacheNames = CacheNames.SYS_DEPT, key = "#bo.deptId"),
-        @CacheEvict(cacheNames = CacheNames.SYS_TENANT_DEPT)
+        @CacheEvict(cacheNames = CacheNames.SYS_TENANT_DEPT, key = "all")
     })
     @Override
     public int updateDept(SysDeptBo bo) {
@@ -362,14 +362,14 @@ public class SysDeptServiceImpl implements ISysDeptService, DeptService {
      */
     @Caching(evict = {
         @CacheEvict(cacheNames = CacheNames.SYS_DEPT, key = "#deptId"),
-        @CacheEvict(cacheNames = CacheNames.SYS_TENANT_DEPT)
+        @CacheEvict(cacheNames = CacheNames.SYS_TENANT_DEPT, key = "all")
     })
     @Override
     public int deleteDeptById(Long deptId) {
         return baseMapper.deleteById(deptId);
     }
 
-    @Cacheable(cacheNames = CacheNames.SYS_TENANT_DEPT)
+    @Cacheable(cacheNames = CacheNames.SYS_TENANT_DEPT, key = "all")
     @Override
     public List<SysDept> selectAllDept() {
         return baseMapper.selectList();
diff --git a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysOssServiceImpl.java b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysOssServiceImpl.java
index eadd009..4b0faba 100644
--- a/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysOssServiceImpl.java
+++ b/ruoyi-modules/ruoyi-system/src/main/java/org/dromara/system/service/impl/SysOssServiceImpl.java
@@ -251,7 +251,6 @@ public class SysOssServiceImpl implements ISysOssService, OssService {
     }
 
 
-
     /**
      * 桶类型为 private 的URL 修改为临时URL时长为120s
      *
@@ -266,4 +265,21 @@ public class SysOssServiceImpl implements ISysOssService, OssService {
         }
         return oss;
     }
+
+    /**
+     * 根据 md5 从缓存或数据库中获取 SysOssVo 对象
+     *
+     * @param md5 文件在数据库中的唯一标识
+     * @return SysOssVo 对象，包含文件信息
+     */
+    @Cacheable(cacheNames = CacheNames.SYS_OSS_IDENTIFIER, key = "#md5")
+    @Override
+    public Long getIdByMd5(String md5) {
+        SysOss sysOss = baseMapper.selectOne(new LambdaQueryWrapper<SysOss>().eq(SysOss::getFileMd5, md5));
+        if (ObjectUtil.isNotNull(sysOss)) {
+            return sysOss.getOssId();
+        } else {
+            return null;
+        }
+    }
 }