从Cloud Function中获取父级数据？

Question

我想在父

中分配const名称值

exports.myFunction = functions.database.ref('/messages/{pushId}/likes')

.onWrite(event => {

    const name = event.parent.data.val().name; // this doesn't work. how do I properly get the name which is located in /messages/{pushId} ?
    });

Answer 1

根据the documentation，这是您从其他路径访问数据的方式：

exports.myFunction = functions.database.ref('/messages/{pushId}/likes')
.onWrite(event => {
     return event.data.ref.parent.child('name').once('value').then(snapshot => {
        const name = snapshot.val();
    });
});

Answer 2

版本更新后

事件＆lt; - （更改，上下文）

event.data＆lt; -change.after

exports.myFunction = functions.database.ref('/messages/{pushId}/likes')
.onWrite((change, context) => {
 return change.after.ref.parent.child('name').once('value').then(snapshot => {
    const name = snapshot.val();
});

}）;