How AngularFire automatically adds back a removed item in a Firebase array

Question

How AngularFire automatically adds back a removed item in a Firebase array

I have been working on a way to remove an item from my $firebaseArray called "boxes".

Here is the "remove" function:

function remove(boxJson) {
        return boxes.$remove(boxJson);
    }

Although it gets removed, I noticed that it immediately reappears:

https://i.stack.imgur.com/FnVeX.png

This is the process for fetching the array:

function getBoxes(screenIndex) {

        var boxesRef = screens
            .child("s-" + screenIndex)
            .child("boxes");

        return $firebaseArray(boxesRef);

    }

I initially thought I might be holding multiple references to the firebaseArray causing this issue, but then realized Firebase should handle it. Any insights?

UPDATE

As a temporary solution, when I manually delete twice with a timeout, it seems to work as expected:

function removeForce(screenIndex, boxId) {

        setTimeout(function () {
            API.removeBox(screenIndex, boxId);
        }, 1000);

        return API.removeBox(screenIndex, boxId);
    }

The structure of the API.removeBox function:

function removeBox(screenIndex, boxId) {

        var boxRef = screens
            .child("s-" + screenIndex)
            .child("boxes")
            .child(boxId);

      return boxRef.remove();
    }

javascript angularjs firebase angularfire

Answer 1

Answer №1

If you need to delete data from Firebase, it's important to remember that the process is asynchronous. According to the documentation, the recommended way to remove an item from Firebase using AngularFire is as follows:

var obj = $firebaseObject(ref);
obj.$remove().then(function(ref) {
  // The data has been deleted locally and in the database
}, function(error) {
  console.log("Error:", error);
});

The $remove() method removes the entire object both locally and from the database. It returns a promise that will be fulfilled once the data has been successfully removed from the server. The promise will include a Firebase reference for the deleted record.

For more information, please refer to the documentation:

Answer 2

If you need to delete data from Firebase, it's important to remember that the process is asynchronous. According to the documentation, the recommended way to remove an item from Firebase using AngularFire is as follows:

var obj = $firebaseObject(ref);
obj.$remove().then(function(ref) {
  // The data has been deleted locally and in the database
}, function(error) {
  console.log("Error:", error);
});

The $remove() method removes the entire object both locally and from the database. It returns a promise that will be fulfilled once the data has been successfully removed from the server. The promise will include a Firebase reference for the deleted record.

For more information, please refer to the documentation:

Answer 3

Answer №2

The main reason for this issue is most likely due to security rules preventing the deletion process.

Once you execute the boxes.$remove function, Firebase immediately triggers the child_removed event on the client side to ensure quick UI updates. Subsequently, it sends the delete command to the Firebase servers for verification and database update.

However, if there exists a security rule on the server that restricts deletions, the server will respond with an error message indicating the failure. In response, the client will fire a child_added event to rectify the UI inconsistencies.

Answer 4

The main reason for this issue is most likely due to security rules preventing the deletion process.

Once you execute the boxes.$remove function, Firebase immediately triggers the child_removed event on the client side to ensure quick UI updates. Subsequently, it sends the delete command to the Firebase servers for verification and database update.

However, if there exists a security rule on the server that restricts deletions, the server will respond with an error message indicating the failure. In response, the client will fire a child_added event to rectify the UI inconsistencies.

Answer 5

Answer №3

It turns out that I inadvertently saved the items again after deleting them, which was a clear oversight on my part:

    function removeSelected(boxes) {
        var selectedBoxes = Selector.getSelectedBoxes(boxes);

        angular.forEach(selectedBoxes, function (box) {

            BoxManager.remove(box);

        });

        Selector.clearSelection(boxes, true);
    }

Upon further review, I realized that in the clearSelection method, I mistakenly updated a field on the boxes and saved them again.

This experience served as a valuable lesson for me on handling data with Firebase. It highlighted the importance of understanding how deleted items are managed within the system, as saving a previously deleted item can unexpectedly revive it without causing any visible bugs at first glance.

Answer 6

It turns out that I inadvertently saved the items again after deleting them, which was a clear oversight on my part:

    function removeSelected(boxes) {
        var selectedBoxes = Selector.getSelectedBoxes(boxes);

        angular.forEach(selectedBoxes, function (box) {

            BoxManager.remove(box);

        });

        Selector.clearSelection(boxes, true);
    }

Upon further review, I realized that in the clearSelection method, I mistakenly updated a field on the boxes and saved them again.

This experience served as a valuable lesson for me on handling data with Firebase. It highlighted the importance of understanding how deleted items are managed within the system, as saving a previously deleted item can unexpectedly revive it without causing any visible bugs at first glance.

Answer 7

Answer №4

For anyone facing a similar issue and struggling to find a solution.

Dealing with event listeners can be tricky, especially when choosing between .on() and .once(). In my experience, this choice caused a significant problem. I was in the middle of a migration task that needed to execute only once

writeRef
    .orderByChild('text_hash')
    .equalTo(addItem.text_hash)
    .on('value', val => { // <-- 
        if (!val.exists()) {
            writeRef.push(addItem)
        }
    });

The issue stemmed from using the .on method, triggering every time there was a change made on FB's console.

By switching to .once, I managed to resolve the problem at hand.

Answer 8

For anyone facing a similar issue and struggling to find a solution.

Dealing with event listeners can be tricky, especially when choosing between .on() and .once(). In my experience, this choice caused a significant problem. I was in the middle of a migration task that needed to execute only once

writeRef
    .orderByChild('text_hash')
    .equalTo(addItem.text_hash)
    .on('value', val => { // <-- 
        if (!val.exists()) {
            writeRef.push(addItem)
        }
    });

The issue stemmed from using the .on method, triggering every time there was a change made on FB's console.

By switching to .once, I managed to resolve the problem at hand.

How AngularFire automatically adds back a removed item in a Firebase array

Answer №1

Answer №2

Answer №3

Answer №4

Similar questions

"Implementing a nested ng-repeat in Angular with a custom class

Collaborating on a single instance across several processes

The node sends a request to the API to retrieve data, which is then stored in an array. Subsequently, another request is

Discover the method of accessing items pushed into an empty array within a view

Utilizing API calls within a loop using AngularJS

Click the navigation bar to toggle it on and off

Questions on how to utilize ES6 Express and static methods

Translating PCRE(PHP) regular expressions into ECMAScript(Javascript) syntax

The link containing special characters like % cannot access the api

What is the reason for the find() method not displaying the most recent data from a MongoDB database in an Express.js application?

Automatically update data in Angular without the need to refresh the page

struggling to retain data within scope when utilizing localstorage in angular

Saving JSON data into an HTML element using Handlebars templating

Identification of inappropriate language in usernames

Guide for using two Async Pipe functions in Angular 7

Transform the hue of symbols within D3-legend

Tips for having <script> update onchange instead of just onload

Execute an asynchronous function in Javascript, then output the returned data to the console

Ways to switch classes within a loop of elements in vue.js

Utilizing Angular partials within specific views with the assistance of ui-router