在Firestore中为文档ID的自定义对象建模的最佳方法是什么? [英] What's the best way to model Custom Object for Document ID in Firestore?

问题描述

说我有一个用户"集合，很高兴他们的ID可以是生成的Firestore documentId，例如:

Say I have a collection of 'Users', and am happy for their ID to be the generated Firestore documentId, something like:

Users Collection
    GENERATED_FIRESTORE_ID1:
        name: "User 1 name"
        ...: etc.
    GENERATED_FIRESTORE_ID2:
        name: "User 2 name"
         ...: etc."

，我正在添加它们，并使用自定义对象来检索它们(目前我正在使用Android，但我想这个问题更笼统).我不想在文档中有多余的"id"字段，只需使用document.getId()方法即可获取生成的Firestore ID.

and I am adding them, and retrieving them with a custom object (I'm using Android at the moment but the question I guess is more generalistic). I don't want to have an extra "id" field in the document, just use the document.getId() method to get the generated firestore ID.

是否存在将POJO映射为不具有单个ID字段的正确方法，但是在查询时将其设置为用于应用程序使用?我正在使用@Exclude注释执行此操作，如下所示:

Is there a correct way to map a POJO to not have an indivual ID field, but when querying set it for application usage? I am doing it using the @Exclude annotation as follows:

public class User {

// as a side question, do I need @exclude on the field or just the getter?
@Exclude
String uId;

String name;
String email;
//... additional fields as normal

public User() {
}

@Exclude
public String getId() {
    return id;
}

public void setId(String id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.displayName = name;
}

//... etc. etc.

}

然后创建User对象并按如下所示设置其ID:

and then I create the User object and set its ID as follows:

 for (DocumentSnapshot doc : documentSnapshots) {
     User user = doc.toObject(User.class);
     user.setId(doc.getId());
     users.add(user );
 }

这很好用，如果确实是这样的话，我深表歉意，但是我是FireStore的新手(我很喜欢它)，并希望确保我做得对.我只是想知道是否有一种方法可以自动完成所有工作，而无需@Exclude，然后在doc.toObject(MyCustomObject.class)

This works fine, and apologies if this is indeed the way, but I'm new to FireStore (am loving it) and want to make sure I'm doing it right. I just wondered if there was a way this would all be automatic, without @Exclude and then manually setting the ID after doc.toObject(MyCustomObject.class)

推荐答案

现在有一个注释-

您可以简单地使用

@DocumentId String uID

@DocumentId String uID

https://firebase.google. com/docs/reference/android/com/google/firebase/firestore/DocumentId.html

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