Mulesoft DataWeave:变换平面列表

Question

我对DataWeave比较陌生，我想知道如何/是否可以使用DataWeave而不是Java转换器来转换如下所示的消息。

如果我有以下用户的JSON负载，以及一个组和一个子组：

[{
    "GROUP": "GROUP_A",
    "SUBGROUP": "SUBGROUP A1",
    "USER": "USER 1"
}, {
    "GROUP": "GROUP_B",
    "SUBGROUP": "SUBGROUP B1",
    "USER": "USER 1"
}, {
    "GROUP": "GROUP_B",
    "SUBGROUP": "SUBGROUP B1",
    "USER": "USER 2"
}, {
    "GROUP": "GROUP_B",
    "SUBGROUP": "SUBGROUP B2",
    "USER": "USER 3"
}, {
    "GROUP": "GROUP_B",
    "SUBGROUP": "SUBGROUP B2",
    "USER": "USER 4"
}, {
    "GROUP": "GROUP_B",
    "SUBGROUP": "SUBGROUP B2",
    "USER": "USER 5"
}]

将有效负载转换为如下结构的DataWeave转换会是什么样子：

[   
    {
        "GROUP": "GROUP_A",
        "SUBGROUPS": [{
            "NAME": "SUBGROUP A1",
            "USERS": ["USER 1"]
        }]
    }, {
        "GROUP": "GROUP_B",
        "SUBGROUPS": [{
            "NAME": "SUBGROUP B1",
            "USERS": ["USER 1", "USER 2"]
        }, {
            "NAME": "SUBGROUP B2",
            "USERS": ["USER 3", "USER 4", "USER 5"]
        }]
    }

]

谢谢你的帮助！

Answer 1

有关DataWeave的开发，请参考DataWeave Reference Documentation。在这种情况下，您可以参阅按…分组一节。要转换上面的消息，请尝试以下脚本：

%dw 1.0
%output application/json
---
payload groupBy $.GROUP pluck {
    GROUP: $$,
    SUBGROUPS: $ groupBy $.SUBGROUP pluck {
        NAME: $$,
        USERS: $.USER
    }
}