无法在 Firestore 中禁用离线数据

问题描述

从我的 Firestore 数据库 删除数据后，我的 Android app 需要一些时间才能意识到数据被删除了，我假设这是由于自动数据缓存而发生的.我的应用与离线使用无关，我想禁用此功能...

After deleting data from my Firestore Database, it takes my Android app some time to realize that the data was deleted, and I assume that it's happening due the auto data cache. My app has nothing to do with offline usage and I'd like to disable this feature...

我已将其添加到我的自定义 Application Class 中:

I have added this in my custom Application Class:

import android.app.Application;
import com.google.firebase.firestore.FirebaseFirestore;
import com.google.firebase.firestore.FirebaseFirestoreSettings;

public class ApplicationClass extends Application {

    @Override
    public void onCreate() {
        super.onCreate();

        FirebaseFirestore db=FirebaseFirestore.getInstance();
        FirebaseFirestoreSettings settings = new FirebaseFirestoreSettings.Builder()
                .setPersistenceEnabled(false)
                .build();
        db.setFirestoreSettings(settings);
    }
}

问题发生在关闭互联网连接并重新打开后(当应用程序仍在运行时，无论是否在后台)- Firestore 模块似乎失去了与服务器的连接，它进行了与预期相反的操作 - 不是停止从缓存中获取数据，而是仅从缓存中获取数据em>.

The problem occurs after turning off the internet connection and than turning it back on (while the app is still running, in the background or not)- the Firestore module seems to lose connection to the server, and it makes the opposite operation than the intended one - instead of stop taking data from the cache, it takes data from the cache only.

例如，调试此代码将始终显示 isFromCache 为 true 并且 documentSnapshot 为空(即使在 server 端 - 它不是空的):

For example, debugging this code will always show that isFromCache is true and documentSnapshot is empty (even though that on the server side - it's not empty):

usersRef.document(loggedEmail).collection("challenges_received").get().addOnSuccessListener(new OnSuccessListener<QuerySnapshot>() {
    @Override
    public void onSuccess(QuerySnapshot documentSnapshots) {
        boolean isFromCache=documentSnapshots.getMetadata().isFromCache();
        if (!documentSnapshots.isEmpty()) {
        }
    }
});

这是正常行为吗?

是否有其他方法可以禁用 Cloud Firestore 中的数据缓存?

Is there another way to disable the data cache in Cloud Firestore?

在自定义Application Class中添加:FirebaseFirestore.setLoggingEnabled(flase);(而不是上面的代码)给出了相同的结果.

Adding: FirebaseFirestore.setLoggingEnabled(flase); (instead of the code above) in the custom Application Class gives the same result.

推荐答案

根据 Cloud Firestore 16.0.0 SDK 更新，有现在解决这个问题:

According to Cloud Firestore 16.0.0 SDK update, there is now a solution to this problem:

您现在可以选择是否要从仅服务器、或仅从缓存中获取数据，例如这(仅用于服务器的示例):

You are now able to choose if you would like to fetch your data from the server only, or from the cache only, like this (an example for server only):

DocumentReference documentReference= FirebaseFirestore.getInstance().document("example");
documentReference.get(Source.SERVER).addOnSuccessListener(new OnSuccessListener<DocumentSnapshot>() {
    @Override
    public void onSuccess(DocumentSnapshot documentSnapshot) {
            //...
    }
});

仅用于缓存，只需将上面的代码更改为 Source.CACHE.

For cache only, just change the code above to Source.CACHE.

默认情况下，这两种方法仍会尝试服务器并回退到缓存.

这篇关于无法在 Firestore 中禁用离线数据的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！