javascript - 如何在firebase中检索当前用户数据

Question

我正在尝试在 .下面的代码仅检索当前登录用户的数据。我对如何按用户名过滤数据感到非常困惑，并尝试了多种方案但无济于事。

我已经尝试使用 firebase 中的 equalTo 方法，但似乎无法让它工作。如何访问数据结构的第二个子级并仍然检索其下面的数据？错误出现在friendRequestFetch 函数中。

JSON

{
  "requests" : {
    "RIXXnKMGxYRPBTe1kBUsNUV9eFL2" : {
      "NQgSxcVKm1N3tnkykUevBM45JLn2" : {
        "name" : "Tom Hanks",
        "photoURL" : "https://firebasestorage.googleapis.com/v0/b/myapp-d0755.appspot.com/o/profilePhotos%2FNQgSxcVKm1N3tnkykUevBM45JLn2?alt=media&token=7822d763-e1e0-421e-88bf-836b34184c2c",
        "receiver" : "RIXXnKMGxYRPBTe1kBUsNUV9eFL2",
        "sent" : 1557800380001,
        "status" : "pending",
        "uid" : "NQgSxcVKm1N3tnkykUevBM45JLn2"
      }
    }
  }
}

代码

export const sendFriendRequest = (item) => {
    const { currentUser } = firebase.auth()
    return (dispatch) => {
        firebase.database().ref(`/friends/requests/${item.uid}/${currentUser.uid}`)//sting interpolation
            .set({
                uid: currentUser.uid,
                //userName: firebase.database().ref(`/users/${currentUser.uid}`).snapshot.val().userName,
                name: currentUser.displayName,
                photoURL: currentUser.photoURL,
                status: "pending",
                sent: firebase.database.ServerValue.TIMESTAMP
            })
            .then(() => {
                dispatch({
                    type: SEND_FRIEND_REQUEST
                });
            });
    };
};

export const friendRequestFetch = () => {
    const { currentUser } = firebase.auth()
    return (dispatch) => {
        firebase.database().ref('/friends/requests')
            .on('value', snapshot => {
                snapshot.forEach(child => { //anytime we get any value call function with an object thats describing the data thats sitting in there
                    dispatch({
                        type: FRIEND_REQUEST_FETCH_SUCCESS,
                        payload: child.val() // this is how we get access to the data at this ref
                    });
                });
            });
    };
};

我需要子值，但仅适用于当前登录的用户。

Answer 1

您可以通过以下两种方法获取当前登录的用户。

1)

firebase.auth().onAuthStateChanged(function(user) {
  if (user) {
    // User is signed in.
  } else {
    // No user is signed in.
  }
});

2)

var user = firebase.auth().currentUser;

在您的情况下currentUser等于firebase.auth()。不是 firebase.auth().currentUser; 。我认为问题就在那里。

有关更多信息，请参阅 firebase 文档 https://firebase.google.com/docs/auth/web/manage-users