How to add to a list in Firebase without overwriting - angularjs

I am trying to create a 'Favorites' section in my app where you hit a button and it is added to a user favorites list in firebase. I am using the ionic platform.
I created a factory to handle the favourites as they come in. and i use the getAuth() function to get the unique userID so i can just pull it when the user logs on. This is my attempt but i am not getting the result i wanted which is simply something like :
< userid >:
{
0: "fav1"
1: "fav2"
}
.factory('Favourites',function($firebaseArray){
var ref = new Firebase("https://experiencett.firebaseio.com/");
var authData = ref.getAuth();
var favs = $firebaseArray(new Firebase('https://experiencett.firebaseio.com/favourites/'+authData.uid+''));
return {
all: function() {
return favs;
},
add: function(){
var up=new Firebase('https://experiencett.firebaseio.com/favourites/');
var usersref=up.child(authData.uid);
usersref.push({3:"paria"});
},

When you call push() you are generating a unique id. While that is great for many use-cases, it is not good here since you want to control the path that is written.
Since you're already constructing the path with child(authData.uid) you can simply update it with update():
usersref.child(authData.uid).update({3: "paria"});
This will either update the existing value at 3 or write the new value for 3, leaving all other keys under /users/<uid> unmodified.
Alternatively if you want to replace the data that already exists at users/<users>, you can use set() instead of update().
This is all covered in the Firebase JavaScript SDK in the section on storing user data. It is not covered in the AngularFire documentation, since there is nothing specific to Angular about it.

Related

Any performance concern when using $firebaseArray to add a new record to Firebase?

I got the following AngularJS sample code from the document regarding how to add a new record to Firebase. It works fine and the new record can be created successfully.
While I also noticed that from the callback we can get all the siblings with the list variable, which is interesting.
My question is that would there be any performance latency when the list is large, say 100,000 records. Can anyone shed light on this?
var list = $firebaseArray(ref);
list.$add({ foo: "bar" }).then(function(ref) {
var id = ref.key();
console.log("added record with id " + id);
list.$indexFor(id); // returns location in the array
});
$firebaseArray synchronizes a collection from the Firebase Database to your client, for easy display in your Angular views. You should never synchronize more data than the user needs to see, and 100,000 records seems very much beyond what a user should ever see.
If you just want to add a new item, you're better off using the Firebase JavaScript SDK directly:
ref.push({ foo: "bar" }).then(function(ref) {
var id = ref.key();
console.log("added record with id " + id);
});
Since AngularFire is built on top of the Firebase JavaScript SDK, it will pick up this change automatically.

Linking Data in Firebase

I am designing a forum and have a layout like this in on my Firebase:
root
|-posts
|-postID1
|-creator: "userOne"
|-creatorUID: "simplelogin:1"
|-text: "Some Text"
|-postID2
|-creator: "userTwo"
|-creatorUID: "simplelogin:2"
|-text: "Some Other Text"
|-profile
|-simplelogin:1
|-firstName: "John"
|-user: "userOne"
|-simplelogin:2
|-firstName: "Sue"
|-user: "userTwo"
On my forum page. I simply use a Angular ng-repeat to get all of the posts on Firebase and list them out. I also want to print out the first name of whoever created the post, but right now, I can only access {{ post.creator }}, which just gives the username of the person who posted. How can I link the post's creator (or creatorUID) with the first name field of that person's profile?
If you're just displaying the the users firstName I would place the users name in the postIDX object.
This would be quicker and produce less requests to Firebase with you going back and fourth with each post to get the usersFirst name.
more information on structuring data and best practices can be found here: https://www.firebase.com/docs/web/guide/structuring-data.html
Updated from response
if you wanted to get the user details then within every request to the postIDx you'd need to do something similar to this (not tested and quick mock up).
var fbRef = new Firebase('firebase path'),
postDetailsObject = {};
fbRef.child('posts').once('value', function(snapshot) {
// loop through each post
snapshot.forEach(function(childSnapshot){
var postDetails = childSnapshot.val(),
profileDetails;
postDetailsObject.post = postDetails;
fbRef.child('profile/' + postDetails.creatorUID).once('value', function(profileData) {
postDetailsObject.profile = profileData;
});
})
});
Then return the postDetailsObject in to angular so you can loop through the single object.

retrieve data from firebase (angularjs)

UPDATE : find my answer here
A little clarity on getting key values using AngularFire v2?
I looked for many sources before asking a simple question but Im just sarting with firebase and I can't manage to use the data the way I want. What I need, is to retrieve two int in my controller (how much "yes" and how much "no" linked to a question.
the data model is the following
question/id/(text, yes, no)
I have a service where I call my data using an id
app.service('QuestionService', function($firebase,$q) {
var _this = this;
//initialize Firebase
var ref = new Firebase('https://basename.firebaseio.com/question');
this.get = function(nb){
var QuestionObject = ref.child(nb);
return $firebase(QuestionObject);
};
return this;
});
I have a controller function where I call some data using a random id
$scope.pickQuestion = function(){
var randomnumber = Math.ceil(Math.random() * 3);
$scope.message = QuestionService.get(randomnumber);
};
and then it works great so I can have something like
{{message.yes}} or {{message.no}} and get the corresponding integer.
My issue, what I want to do, is to pass this "message.no" value to my controller. I don't know what to do. I can't manage to get the value directly inside the controller (it works only inside the view) and I can't manage to pass the value to my controller from the view. I tried a
ng-init="functionName({{message.yes}}, {{message.no}})"
but it return an error into the console. (however the source a displayed correctly)
Does someone could guide me into the right direction?
Thanks

AngularFire equivalent to $setPristine?

I'm trying to understand the correct workflow to create a $setPristine equivalent with my Firebase data.
My workflow is as follows:
1) Create Firebase object (via the Angularfire Generator 'SyncData')
2) Form data modifies the $firebase object.
3) To update the remote model, I use myRef.$save()
All of that works well. Now, I'm trying to add a "reset" button on the form, so that the locally modified data will revert back to the remotely stored data.
So far, I'm running into problems. I've tried reinitializing the firebase reference eg myRef = syncData('/my/path') but not only does that now work, but it is destroying the remote data object!
What is the correct way to re-pull the remote data to use in my Angular model?
I know this is an old question, but I ran into this issue myself.
After some searching around I found this post: http://grokbase.com/t/gg/firebase-angular/1499haaq4j/editing-data-as-a-copy
Which led me to an outdated code snippet (2 months lol XD) from #Kato: https://gist.github.com/katowulf/8eaa39eab05a4d975cd9
I modified this to work with Firebase 2.3.1 and AngularFire 1.1.3:
app.factory('ResetFactory', function($firebaseArray) {
return $firebaseArray.$extend({
reset: function(itemOrIndex) {
var key, self;
self = this;
key = self.$keyAt(itemOrIndex);
self.$ref().child(key).once('value', function(snap) {
self.$$updated(snap);
});
}
});
});
Which can be called via:
var comments = new RevertFactory(ref.child('comments'));
# variable comment is for example an ng-repeat that's being edited
comments.reset(comment);

Parse.com iOS SDK: Create New Related Object on Object Save

I'm trying to use cloud code to create a new 'credit' every time a new User is created, the credit is for that user, as in it is a related object. For some reason I can't get writing to the 'Logs' tab to work using lines like console.log(tell me what is going on!); so I'm stumped, and with no way of knowing where I've gone wrong.
Parse.Cloud.afterSave("User", function(request) {
var Credit = Parse.Object.extend("credit");
var credit = new Credit();
credit.set("parent", request.object);
credit.set("expiry", null);
credit.set("type", "Opening");
credit.save();
});
You need to change it to this:
Parse.Cloud.afterSave(Parse.User, function(request)
Parse.User rather than "User".
For whatever reason this doesn't seem to be in the docs here: https://www.parse.com/docs/cloud_code_guide#functions-aftersave

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