问题描述
我正在尝试在 firebase 数据库中更新(添加)一些子项.在这种情况下,我需要使用更新对象更新节点而不用 Google Cloud Function 覆盖所有子节点.
I am trying to update (adding) some children on a firebase database. On this scenario I need to update a node without overwriting all the child nodes with Google Cloud Function using an update Object.
这个问题来自这个问题:如何使用更新对象更新节点而不用 Google Cloud Function 覆盖所有子节点?
我的数据结构是这样的:
My data structure is like this:
root: {
doors: {
111111111111: {
MACaddress: "111111111111",
inRoom: "-LBMH_8KHf_N9CvLqhzU", // I will need this value for the clone's path
ins: {
// I am creating several "key: pair"s here, something like:
1525104151100: true,
1525104151183: true,
}
},
222222222222: {
MACaddress: "222222222222",
inRoom: "-LBMH_8KHf_N9CvLqhzU", // I will need this value for the clone's path
ins: {
// I am creating several "key: pair"s here, something like:
2525104157710: true,
2525104157711: true,
}
}
},
rooms: {
-LBMH_8KHf_N9CvLqhzU: {
ins: {
// I want the function to clone the same data here:
1525104151100: true,
1525104151183: true,
}
}
}
我正在尝试查询现有的ins"并在对象上循环以在添加它们之前检测它是否存在,这样我就可以在键中添加后缀以防它们已经存在.这是我的功能.
I am trying to to query the existing "ins" and loop over the object to detect if it exists before I add them so I can add a suffix to the key in case they are already there. This is my function ate the moment.
exports.updateBuildingsOuts = functions.database.ref('/doors/{MACaddress}').onWrite((change, context) => {
const afterData = change.after.val(); // data after the write
const roomPushKey = afterData.inRoom;
const ins = afterData.ins;
const updates = {};
// forEach loop to update the keys individually
Object.keys(ins).forEach(key => {
parentPath = ['/rooms/' + roomPushKey + '/ins/']; // defining the path where I want to check if the data exists
// querying the "ins"
admin.database().ref().parentPath.on('value', function(snapshot) {
if (snapshot.hasChild(key)) {
updates['/rooms/' + roomPushKey + '/ins/' + key + "_a"] = true; // define 'updates' Object adding a suffix "_a"
return admin.database().ref().update(updates); // do the update adding the suffix "_a"
} else {
updates['/rooms/' + roomPushKey + '/ins/' + key] = true; // define update Object without suffix
return admin.database().ref().update(updates); // do the 'updates' without suffix
}
});
});
此云函数正在检索错误:
This cloud function is retrieving an Error:
TypeError:无法读取未定义的属性on"在 Object.keys.forEach.key
我确信我过于复杂了,但我无法为此找到更清晰的逻辑.
I am sure I overcomplicating but I haven't been able to find a cleaner logic for this.
您对如何精益求精有什么建议吗?可能吗?
Would you have any suggestions on how to do this leanly? Is it possible?
推荐答案
你可以这样做:
let afterIns;
exports.updateRoom = functions.database.ref('/doors/{MACaddress}').onWrite((change, context) => {
const beforeData = change.before.val(); //data before
const insBefore = beforeData.ins;
const afterData = change.after.val(); // data after the write
const roomPushKey = afterData.inRoom;
afterIns = afterData.ins;
return admin.database().ref().update(updates);
const updates = {};
Object.keys(ins).forEach(key => {
if (insBefore.hasOwnProperty(key)) { // checking if the insBefore object has a key equal to value 'key'
//True -> add an extra character at the existing key
updates['/rooms/' + roomPushKey + '/ins/' + key + '_a'] = true; //<- _a being the extra character
} else {
updates['/rooms/' + roomPushKey + '/ins/' + key] = true;
}
});
return admin.database().ref().update(updates);
}).catch(error => {
console.log(error);
//+ other error treatment if necessary
});
不要忘记函数返回change.before.val();
之前的数据(除了之后的数据),因此你不必做admin.database().ref().parentPath.on('value', function(snapshot) {
Don't forget the function returns the data before change.before.val();
(in addition to the data after), therefore you don't have to do admin.database().ref().parentPath.on('value', function(snapshot) {
评论后编辑
这应该可以,但我还没有测试过.您可能需要测试 insBefore
除了测试它是否为空之外未定义.我让你微调.
This should work, but I haven't test it. You may need to test is insBefore
is undefined in addition to testing it is null. I let you fine tune it.
let insAfter;
let roomPushKey ;
exports.updateRoomIns = functions.database.ref('/doors/{MACaddress}').onWrite((change, context) => {
const afterData = change.after.val(); // data after the write
roomPushKey = afterData.inRoom;
insAfter = afterData.ins;
return admin.database().ref('/rooms/' + roomPushKey).once('value').then(snapshot => {
const insBefore = snapshot.val().ins;
const updates = {};
if (insBefore === null || insBefore === undefined ) {
Object.keys(insAfter).forEach(key => {
updates['/rooms/' + roomPushKey + '/ins/' + key] = true;
});
} else {
Object.keys(insAfter).forEach(key => {
if (insBefore.hasOwnProperty(key)) {
updates['/rooms/' + roomPushKey + '/ins/' + key + '_a'] = true;
} else {
updates['/rooms/' + roomPushKey + '/ins/' + key] = true;
}
});
}
return admin.database().ref().update(updates);
});
});.catch(error => {
console.log(error);
//+ other error treatment if necessary
});
这篇关于如何使用 Google Cloud Function 查询现有子代并遍历 Object 以检测它是否存在于 Firebase 中?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!