相关推荐完成

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

@@ -162,15 +162,28 @@ public class BlogApi {
     }
 
     @Anonymous
-    @ApiOperation("查看标签下的博客列表")
+    @ApiOperation("根据标签查找博客列表")
     @GetMapping("/tag/{tagId}/blogs")
     public Response<?> getBlogsByTagId(@PathVariable("tagId") String tagId , @Valid PageForm pageForm , BindingResult result) {
         if (result.hasErrors()) {
             return Response.fieldError(result.getFieldError());
         }
 
-        IPage<Blog> blogPage = blogService.getBlogPageBytagId(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);
     }
+
+    @Anonymous
+    @ApiOperation("相关博客")
+    @GetMapping("/blog/{blogId}/recommends")
+    public Response<?> getRelatedBlogs (@PathVariable("blogId") String blogId , @Valid PageForm pageForm, BindingResult bindingResult) {
+        if (bindingResult.hasErrors()) {
+            return Response.fieldError(bindingResult.getFieldError());
+        }
+        IPage<Blog> blogPage = blogService.getRelatedBlogPage(pageForm.getPage() , pageForm.getSize() , blogId);
+        PageVO<Blog> blogPageVO = new PageVO<>(blogPage);
+        return Response.success(blogPageVO);
+    }
+
 }

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

@@ -2,6 +2,10 @@ package cn.meteor.beyondclouds.modules.blog.mapper;
 
 import cn.meteor.beyondclouds.modules.blog.entity.BlogTag;
 import com.baomidou.mybatisplus.core.mapper.BaseMapper;
+import com.baomidou.mybatisplus.core.metadata.IPage;
+import org.apache.ibatis.annotations.Select;
+
+import java.util.Collection;
 
 /**
  * <p>
@@ -13,4 +17,11 @@ import com.baomidou.mybatisplus.core.mapper.BaseMapper;
  */
 public interface BlogTagMapper extends BaseMapper<BlogTag> {
 
+    /**
+     * 根据博客ID获取相关的博客ids
+     * @param page
+     * @param tagIds
+     * @return
+     */
+    IPage<String> selectRelatedBlogIds(IPage<?> page, Collection<String> tagIds);
 }

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

@@ -64,4 +64,15 @@
             #{blogId}
         </foreach>
     </select>
+
+    <select id="selectRelatedBlogIds">
+        select distinct (blog_id)
+        from blog_tag
+        where tag_id in
+        <foreach collection="tagIds" item="tagId" index="index" open="(" close=")" separator=",">
+            #{tagId}
+        </foreach>
+    </select>
+
+
 </mapper>

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

@@ -95,6 +95,16 @@ public interface IBlogService extends IService<Blog> {
      * @param tagId
      * @return
      */
-    IPage<Blog> getBlogPageBytagId(Integer pageNumber , Integer pageSize , String tagId);
+    IPage<Blog> getBlogPageByTagId(Integer pageNumber , Integer pageSize , String tagId);
+
+
+    /**
+     * 相关博客
+     * @param page
+     * @param size
+     * @param blogId
+     * @return
+     */
+    IPage<Blog> getRelatedBlogPage(Integer page, Integer size, String blogId);
 }
 

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

@@ -4,6 +4,8 @@ import cn.meteor.beyondclouds.modules.blog.entity.BlogTag;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.extension.service.IService;
 
+import java.util.Collection;
+
 /**
  * <p>
  * 博客标签表，用来记录博客里面引用了哪些标签 服务类
@@ -22,4 +24,12 @@ public interface IBlogTagService extends IService<BlogTag> {
      * @return
      */
     IPage<BlogTag> getBlogIdByTagId (Integer pageNumber , Integer pageSize , String tagId);
+
+    /**
+     * 根据博客ID获取相关的博客ID
+     * @param page
+     * @param tagIds
+     * @return
+     */
+    IPage<String> getRelatedBlogIds(IPage<String> page, Collection<String> tagIds);
 }

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

@@ -22,6 +22,7 @@ import cn.meteor.beyondclouds.modules.topic.service.ITopicService;
 import cn.meteor.beyondclouds.modules.user.entity.User;
 import cn.meteor.beyondclouds.modules.user.service.IUserService;
 import cn.meteor.beyondclouds.util.AbstractUtils;
+import cn.meteor.beyondclouds.util.PageUtils;
 import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
 import com.baomidou.mybatisplus.core.metadata.IPage;
 import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
@@ -36,6 +37,7 @@ import org.springframework.util.CollectionUtils;
 import org.springframework.util.StringUtils;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.List;
 import java.util.stream.Collectors;
 
@@ -473,7 +475,7 @@ public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IB
     }
 
     @Override
-    public IPage<Blog> getBlogPageBytagId(Integer pageNumber, Integer pageSize, String tagId) {
+    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<>();
@@ -500,4 +502,29 @@ public class BlogServiceImpl extends ServiceImpl<BlogMapper, Blog> implements IB
         }
         return blogPage;
     }
+
+    @Override
+    public IPage<Blog> getRelatedBlogPage(Integer pageNumber, Integer pageSize, String blogId) {
+        // 1.查找博客引用的所有标签id
+        QueryWrapper<BlogTag> blogTagQueryWrapper = new QueryWrapper<>();
+        List<BlogTag> blogTagList = blogTagService.list(blogTagQueryWrapper);
+        List<String> tagIds = blogTagList.stream()
+                .map(BlogTag::getTagId)
+                .collect(Collectors.toList());
+
+        // 如果博客没有引用标签，则构造一个空的分页返回
+        if (CollectionUtils.isEmpty(tagIds)) {
+            return PageUtils.emptyPage();
+        }
+
+        // 如果博客没有引用了标签，则查询引用的标签下的所有博客ID的分页
+        IPage<String> page = new Page<>(pageNumber, pageSize);
+        IPage<String> blogIdPage = blogTagService.getRelatedBlogIds(page, tagIds);
+        List<String> blogIds = blogIdPage.getRecords();
+        if (CollectionUtils.isEmpty(blogIds)) {
+            return PageUtils.emptyPage();
+        } else {
+            return blogMapper.listByIdsWithTags(blogIds);
+        }
+    }
 }

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

@@ -9,6 +9,8 @@ import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
 import org.springframework.stereotype.Service;
 
+import java.util.Collection;
+
 /**
  * <p>
  * 博客标签表，用来记录博客里面引用了哪些标签 服务实现类
@@ -20,6 +22,11 @@ import org.springframework.stereotype.Service;
 @Service
 public class BlogTagServiceImpl extends ServiceImpl<BlogTagMapper, BlogTag> implements IBlogTagService {
 
+    private BlogTagMapper blogTagMapper;
+
+    public BlogTagServiceImpl(BlogTagMapper blogTagMapper) {
+        this.blogTagMapper = blogTagMapper;
+    }
 
     @Override
     public IPage<BlogTag> getBlogIdByTagId(Integer pageNumber, Integer pageSize, String tagId) {
@@ -29,4 +36,9 @@ public class BlogTagServiceImpl extends ServiceImpl<BlogTagMapper, BlogTag> impl
         queryWrapper.eq("tag_id", tagId);
         return page(page , queryWrapper);
     }
+
+    @Override
+    public IPage<String> getRelatedBlogIds(IPage<String> page, Collection<String> tagIds) {
+        return blogTagMapper.selectRelatedBlogIds(page, tagIds);
+    }
 }

src/main/java/cn/meteor/beyondclouds/util/PageUtils.java

+package cn.meteor.beyondclouds.util;
+
+import cn.meteor.beyondclouds.modules.blog.entity.Blog;
+import com.baomidou.mybatisplus.core.metadata.IPage;
+import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
+
+import java.util.List;
+
+/**
+ * @author meteor
+ */
+public class PageUtils {
+    public static <T>IPage<T> emptyPage() {
+        IPage<T> page = new Page<>();
+        page.setTotal(0L);
+        page.setPages(0L);
+        page.setCurrent(0);
+        page.setRecords(List.of());
+        return page;
+    }
+}