优化根据tatId查询博客列表

src/main/java/cn/meteor/beyondclouds/modules/blog/api/BlogApi.java

@@ -19,7 +19,6 @@ import io.swagger.annotations.Api;
 import io.swagger.annotations.ApiOperation;
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.data.domain.Page;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;
@@ -170,7 +169,7 @@ public class BlogApi {
             return Response.fieldError(result.getFieldError());
         }
 
-        IPage<Blog> blogPage = blogService.getBlogsBytagId(pageForm.getPage(), pageForm.getSize(), tagId);
+        IPage<Blog> blogPage = blogService.getBlogPageBytagId(pageForm.getPage(), pageForm.getSize(), tagId);
         PageVO<Blog> blogPageVO = new PageVO<>(blogPage);
         return Response.success(blogPageVO);
     }

src/main/java/cn/meteor/beyondclouds/modules/blog/mapper/BlogMapper.java

@@ -7,6 +7,8 @@ import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.core.toolkit.Constants;
 import org.apache.ibatis.annotations.Param;
 
+import java.util.Collection;
+
 /**
  * <p>
  * 博客表 Mapper 接口
@@ -24,4 +26,11 @@ public interface BlogMapper extends BaseMapper<Blog> {
      * @return
      */
     IPage<Blog> selectPageWithTags(IPage<Blog> page, @Param(Constants.WRAPPER)QueryWrapper<?> queryWrapper);
+
+    /**
+     * 根据查询条件分页查询博客获取标签
+     * @param blogIds
+     * @return
+     */
+    IPage<Blog> listByIdsWithTags(Collection<String> blogIds);
 }

src/main/java/cn/meteor/beyondclouds/modules/blog/mapper/xml/BlogMapper.xml

@@ -44,4 +44,24 @@
             ${ew.customSqlSegment}
         </if>
     </select>
+
+
+    <select id="listByIdsWithTags" resultMap="blogWithTagsResultMap">
+        select
+        b.*,
+        t.tag_id,
+        t.tag_name,
+        t.tag_type,
+        t.create_time,
+        t.update_time
+        from blog b
+        left join blog_tag bt
+        on b.blog_id = bt.blog_id
+        left join tag t
+        on t.tag_id = bt.tag_id
+        where blog_id in
+        <foreach collection="blogIds" item="blogId" index="index" open="(" close=")" separator=",">
+            #{blogId}
+        </foreach>
+    </select>
 </mapper>

src/main/java/cn/meteor/beyondclouds/modules/blog/service/IBlogService.java

@@ -95,6 +95,6 @@ public interface IBlogService extends IService<Blog> {
      * @param tagId
      * @return
      */
-    IPage<Blog> getBlogsBytagId(Integer pageNumber , Integer pageSize , String tagId);
+    IPage<Blog> getBlogPageBytagId(Integer pageNumber , Integer pageSize , String tagId);
 }
 

src/main/java/cn/meteor/beyondclouds/modules/blog/service/impl/BlogServiceImpl.java

@@ -473,15 +473,31 @@ public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IB
     }
 
     @Override
-    public IPage<Blog> getBlogsBytagId(Integer pageNumber, Integer pageSize, String tagId) {
-        IPage<Blog> blogPage = new Page<>(pageNumber , pageSize);
-        //获取当tagId下的所有blogId
-        List<String> blogIds = blogTagService.getBlogIdByTagId(pageNumber, pageSize, tagId)
-                                .getRecords().stream().map(BlogTag::getBlogId).collect(Collectors.toList());
+    public IPage<Blog> getBlogPageBytagId(Integer pageNumber, Integer pageSize, String tagId) {
+        // 查询blogTagPage
+        IPage<BlogTag> page = new Page<>(pageNumber , pageSize);
+        QueryWrapper<BlogTag> blogTagQueryWrapper = new QueryWrapper<>();
+        blogTagQueryWrapper.eq("tag_id", tagId);
+        IPage<BlogTag> blogTagPage = blogTagService.page(page, blogTagQueryWrapper);
 
-        //批量查找博客
-        QueryWrapper<Blog> blogQueryWrapper = new QueryWrapper<>();
-        blogQueryWrapper.in("b.blog_id", blogIds);
-        return blogMapper.selectPageWithTags(blogPage,blogQueryWrapper);
+
+        // 根据blogTagPage构造博客分页
+        List<String> blogIds = blogTagPage.getRecords().stream()
+                .map(BlogTag::getBlogId)
+                .collect(Collectors.toList());
+
+        IPage<Blog> blogPage = new Page<>();
+        blogPage.setTotal(blogTagPage.getTotal());
+        blogPage.setCurrent(blogTagPage.getCurrent());
+        blogPage.setPages(blogTagPage.getPages());
+        blogPage.setSize(blogTagPage.getSize());
+
+        if (!CollectionUtils.isEmpty(blogIds)) {
+            blogPage.setRecords(List.of());
+        } else {
+            //批量查找博客
+            return blogMapper.listByIdsWithTags(blogIds);
+        }
+        return blogPage;
     }
 }