如何用map.reduce将团队对象数组转换为嵌套分组格式？

问题 #

需要将给定的对象数组转换为指定格式，要求使用map+reduce方法实现，以user_name、user_id和team_details_id作为参考依据。

原始数据 #

let result =  [
    {
        "team_details_id": 1,
        "team_name": "Avengers",
        "team_description": null,
        "date_created": "2022-11-03T09:31:13.000Z",
        "date_updated": "2022-11-03T09:31:13.000Z",
        "created_by": "23",
        "updated_by": null,
        "team_participants_id": 2,
        "user_id": 101,
        "user_name": "test 2",
        "email_id": "test2@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    },
    {
        "team_details_id": 1,
        "team_name": "Avengers",
        "team_description": null,
        "date_created": "2022-11-03T09:31:13.000Z",
        "date_updated": "2022-11-03T09:31:13.000Z",
        "created_by": "23",
        "updated_by": null,
        "team_participants_id": 3,
        "user_id": 102,
        "user_name": "test 3",
        "email_id": "test3@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    },
    {
        "team_details_id": 1,
        "team_name": "Avengers",
        "team_description": null,
        "date_created": "2022-11-03T09:31:13.000Z",
        "date_updated": "2022-11-03T09:31:13.000Z",
        "created_by": "23",
        "updated_by": null,
        "team_participants_id": 4,
        "user_id": 103,
        "user_name": "test 4",
        "email_id": "test4@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    },
    {
        "team_details_id": 1,
        "team_name": "Avengers",
        "team_description": null,
        "date_created": "2022-11-03T09:34:24.000Z",
        "date_updated": "2022-11-03T09:34:24.000Z",
        "created_by": "23",
        "updated_by": "23",
        "team_participants_id": 13,
        "user_id": 104,
        "user_name": "test 5",
        "email_id": "test5@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    },
    {
        "team_details_id": 5,
        "team_name": "KantaraBuilders",
        "team_description": null,
        "date_created": "2022-11-03T09:35:23.000Z",
        "date_updated": "2022-11-03T09:35:23.000Z",
        "created_by": "23",
        "updated_by": null,
        "team_participants_id": 16,
        "user_id": 105,
        "user_name": "test 6",
        "email_id": "test6@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    },
    {
        "team_details_id": 5,
        "team_name": "KantaraBuilders",
        "team_description": null,
        "date_created": "2022-11-03T09:35:23.000Z",
        "date_updated": "2022-11-03T09:35:23.000Z",
        "created_by": "23",
        "updated_by": null,
        "team_participants_id": 17,
        "user_id": 106,
        "user_name": "test 7",
        "email_id": "test7@gmail.com",
        "role_id": 3,
        "is_active": 1,
        "access_code": null
    }
];

期望格式 #

let formattedResponse = [{
    "team_details_id": 1,
    "team_name": "Avengers",
    "participant_list":[{
        "user_id": 101,
        "user_name": "test 2",
        "email_id": "test2@gmail.com",
        "role_id": 3
    },{
        "user_id": 102,
        "user_name": "test 3",
        "email_id": "test3@gmail.com",
        "role_id": 3
    },
    {
        "user_id": 103,
        "user_name": "test 4",
        "email_id": "test4@gmail.com",
        "role_id": 3
    },
    {
        "user_id": 104,
        "user_name": "test 5",
        "email_id": "test5@gmail.com",
        "role_id": 3
    }]
},
{
    "team_details_id": 5,
    "team_name": "KantaraBuilders",
    "participant_list":[{
        "user_id": 105,
        "user_name": "test 6",
        "email_id": "test6@gmail.com",
        "role_id": 3
    },{
        "user_id": 106,
        "user_name": "test 7",
        "email_id": "test7@gmail.com",
        "role_id": 3
    }]
}];

解决方案 #

实现思路 #

1. 用reduce按team_details_id分组，将同一团队的参与者聚合到participant_list
2. 依据user_id和user_name过滤重复参与者
3. 用Object.values()将分组后的键值对对象转为目标数组格式

代码实现 #

const formattedResponse = Object.values(result.reduce((acc, item) => {
    const teamId = item.team_details_id;
    
    // 初始化团队信息（如果不存在）
    if (!acc[teamId]) {
        acc[teamId] = {
            team_details_id: teamId,
            team_name: item.team_name,
            participant_list: []
        };
    }
    
    // 检查参与者是否已存在，避免重复添加
    const isDuplicate = acc[teamId].participant_list.some(p => 
        p.user_id === item.user_id && p.user_name === item.user_name
    );
    
    if (!isDuplicate) {
        acc[teamId].participant_list.push({
            user_id: item.user_id,
            user_name: item.user_name,
            email_id: item.email_id,
            role_id: item.role_id
        });
    }
    
    return acc;
}, {}));

console.log(formattedResponse);

代码说明 #

• 分组逻辑：以team_details_id为键，将同一团队的所有条目聚合到同一个对象下
• 去重逻辑：通过some方法校验user_id和user_name，避免重复添加同一用户
• 格式转换：Object.values()将reduce生成的键值对结构转为数组，匹配目标格式

内容的提问来源于stack exchange，提问作者Pankaj Dhumal