demo_34 评论内容实现_3 从数据库加载评论

本节目的:从数据库获取对应文章的评论加载到页面

1. 实现加载评论样式效果

 2. 创建获取评论云函数 get_comments,并配置运行测试参数

'use strict';
const db = uniCloud.database()
const $ = db.command.aggregate
exports.main = async (event, context) => {
    const {
        user_id,
        article_id,
    } = event

    const list = await db.collection('article')
        .aggregate()
        .match({
            _id: article_id
        })
        // 拆分数组中的每个文档为多个
        .unwind('$comments')
        .project({
            _id: 0,
            // 只返回 comments
            comments: 1
        })
        // 指定字段作为根节点
        .replaceRoot({
            newRoot: '$comments'
        })
        .end()
    //返回数据给客户端
    return {
        code: 200,
        msg: '数据请求成功',
        data: list.data
    }
};

// data[0] 是一个对象,把对象替换掉,内容为原对象value值(数组)里的每一项

// 未拆分之前返回结果
// {
//  "code": 200,
//  "data": [{
//      "comments": [{
//          "author": {
//              "author_id": "5f45afe33c788800019dfb0b",
//              "author_name": "Java架构师讲师团",
//              "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//              "professional": "架构师"
//          },
//          "comment_content": "评论2",
//          "comment_id": "4y4z5caxzwk0",
//          "create_time": 1599608617064,
//          "replys": []
//      }, {
//          "author": {
//              "author_id": "5f45afe33c788800019dfb0b",
//              "author_name": "Java架构师讲师团",
//              "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//              "professional": "架构师"
//          },
//          "comment_content": "评论1",
//          "comment_id": "1uv9hscv45kw",
//          "create_time": 1599608595513,
//          "replys": []
//      }, {
//          "author": {
//              "author_id": "5f45afe33c788800019dfb0b",
//              "author_name": "Java架构师讲师团",
//              "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//              "professional": "架构师"
//          },
//          "comment_content": "评论成功",
//          "comment_id": "5156s0kekqk0",
//          "create_time": 1599524585856,
//          "replys": []
//      }]
//  }],
//  "msg": "数据请求成功"
// }

// 拆分之后
// {
//  "code": 200,
//  "msg": "数据请求成功",
//  "data": [{
//      "comment_id": "4y4z5caxzwk0",
//      "comment_content": "评论2",
//      "create_time": 1599608617064,
//      "author": {
//          "author_id": "5f45afe33c788800019dfb0b",
//          "author_name": "Java架构师讲师团",
//          "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//          "professional": "架构师"
//      },
//      "replys": []
//  }, {
//      "comment_id": "1uv9hscv45kw",
//      "comment_content": "评论1",
//      "create_time": 1599608595513,
//      "author": {
//          "author_id": "5f45afe33c788800019dfb0b",
//          "author_name": "Java架构师讲师团",
//          "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//          "professional": "架构师"
//      },
//      "replys": []
//  }, {
//      "comment_id": "5156s0kekqk0",
//      "comment_content": "评论成功",
//      "create_time": 1599524585856,
//      "author": {
//          "author_id": "5f45afe33c788800019dfb0b",
//          "author_name": "Java架构师讲师团",
//          "avatar": "//img2.sycdn.imooc.com/5dafce1a00013fd501400140-160-160.jpg",
//          "professional": "架构师"
//      },
//      "replys": []
//  }]
// }

测试参数:

{
"user_id": "5f45afe33c788800019dfb0b",
"article_id": "5f45afe0875241000188959f"
}

3. 页面加载

3.1 获取

 3.2 渲染及传值给组件

 3. 子组件渲染

原文地址:https://www.cnblogs.com/luwei0915/p/13660835.html