=============
后端_文章归档
=============

每篇文章都有一个创建时间，统计创建于某年某月的文章数即文章归档。

1 (非持久化)数据对象

1.1 归档数据对象

/ysdblog-api/src/main/java/com/weihome/ysdblog/dao/dos/ArchiveDo.java：

@Data
public class ArchiveDo {
    private Integer year;
    private Integer month;
    private Long count;
}

2 文章数据访问

2.1 文章数据访问接口

/ysdblog-api/src/main/java/com/weihome/ysdblog/dao/mapper/ArticleMapper.java：

public interface ArticleMapper extends BaseMapper<Article> {
    /**
     * 查询文章归档
     */
    List<ArchiveDo> archive();
}

2.2 文章数据访问实现

SQL> select from_unixtime(create_date/1000, '%Y') as year, from_unixtime(create_date/1000, '%m') as month, count(*) from t_article group by year, month

/ysdblog-api/src/main/resources/com/weihome/ysdblog/dao/mapper/ArticleMapper.xml：

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.weihome.ysdblog.dao.mapper.ArticleMapper">
    <!-- List<ArchiveDo> archive() -->
    <select id="archive" resultType="com.weihome.ysdblog.dao.dos.ArchiveDo">
        select from_unixtime(create_date/1000, '%Y') as year,
        from_unixtime(create_date/1000, '%m') as month,
        count(*) as count from t_article group by year, month
    </select>
</mapper>

3 文章服务

3.1 文章服务接口

/ysdblog-api/src/main/java/com/weihome/ysdblog/service/ArticleService.java：

public interface ArticleService {
    ...
    /**
     * 查询文章归档
     */
    public Result archive();
    ...
}

3.2 文章服务实现

/ysdblog-api/src/main/java/com/weihome/ysdblog/service/impl/ArticleServiceImpl.java：

...
public class ArticleServiceImpl implements ArticleService {
    ...
    @Override
    public Result archive() {
        List<ArchiveDo> archiveDos = articleMapper.archive();
        return Result.success(archiveDos);
    }
    ...
}

4 文章控制器

/ysdblog-api/src/main/java/com/weihome/ysdblog/controller/ArticleController.java：

...
public class ArticleController {
    ...
    /**
     * 查询文章归档
     */
    @GetMapping("archive")
    public Result archive() {
        return articleService.archive();
    }
    ...
}

5 运行测试

Postman
    GET
        localhost:8888/article/archive
--------------------------------------
{
    "success": true,
    "code": 200,
    "msg": "success",
    "data": [
        {
            "year": 2022,
            "month": 4,
            "count": 2
        }
    ]
}