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How would I cycle through all child nodes in Firebase and read all data nodes inside them in Javascript?

I have a system where each user has permissions to read one or more specific nodes (but not all). How would I set up so I can cycle through all the child nodes in my database when reading and it will subsequently only read the ones the user has permission for?
Thanks so much!
This is what I have to currently:
(There are more than 2 stores)
var database = firebase.database();
var storeOneRef = database.ref().child('storeOne');
var storeTwoRef = database.ref().child('storeTwo');
var allStores = [ { ref: storeOneRef, name: 'storeOne'},
{ ref: storeTwoRef, name: 'storeTwo'} ];
for (var i = 0; i < allStores.length; i++) {
allStores[i].ref.once('value', (snapshot) => {
var data = snapshot.val();
});
}
This is what the database looks like:

It looks like your database has all sales nodes underneath the store/retail node to which they belong. If one of your store/retailers already has read access to their own node, then they will unconditionally have access to all their own sales. There is actually nothing you can do to prevent this. If someone has read access at any node, they implicitly have read access to all child nodes under that one.

UI5 remove duplicate feed list items

I have a Feed List for posting comments in my UI5 xml view
<layout:content>
<m:FeedInput post="onFeedPost" class="sapUiSmallMarginTopBottom"/>
<m:List id="feedList" showSeparators="Inner" items="{path: '/table', sorter: {path: 'DATE', descending: true}}">
<m:FeedListItem sender="{MEMBERID}" timestamp="{DATE}" text="{COMMENT}" convertLinksToAnchorTags="All"/>
</m:List>
</layout:content>
I want to not display duplicate comments that have the same text and date, but keep them in the database. My idea was to in the controller iterate over over the items to do this, but I am not sure what to do with the resulting array
var results = [];
var comments = feed.getItems();
for (var n = 0; n < comments.length - 1; n++) {
var contained = false;
for (var m = n + 1; m < comments.length; m++) {
if (comments[n].getText() === comments[m].getText() &&
comments[n].getDate() === comments[m].getDate()) {
comments.pop(m);
contained = true;
if (!results.includes(comments[n])) {
results.push(comments[n]);
}
}
}
if (!contained && !results.includes(comments[n])) {
results.push(comments[n]);
}
}
// replace list items with results array
I can't figure out how to replace the feed list's items with the new array as there is a getItems function but not a setItems function. It occurs to me there is probably a simpler more idiomatic UI5 way to do this but I haven't found it yet.

First off, the correct way to handle this situation is in the OData service. The service should remove the duplicates before sending the data to the client. If we assume, however, that you can't do this server side, then you have some options.
1.) Do not bind the list items to anything. Instead, use the ODataModel to read the data, then filter out duplicates, create a new list item and add it to the list
Read the data using the ODataModel, then pass the results to a method that will filter and add them items to the list
oModel.read("/EntitySet", {
success: function(oResponse) {
this._addCommentsToList(oResponse.results)
}.bind(this)
})
In your method to handle the results, you'll need to do three things -- create a new FeedListItem, set the binding context of the list item, and then add the list item to the list
var aDistinctComments = //use your logic to filter out duplicates
aDistinctComments.forEach(function(oComment) {
//to set the binding context, you'll need the entity key/path
var sCommentKey = oModel.createKey("/EntitySet", oComment)
//create a new binding context
var oContext = oModel.createBindingContext(sCommentKey)
//create a new FeedListItem
var oItem = new FeedListItem({
sender: "{MemberId}",
...
});
//set the context of the item and add it to the list
oItem.setBindingContext(oContext);
oList.addItem(oItem);
})
2.) Bind the list directly to the OData entity set and then when the list receives the data, iterate over the items and hide the duplicates
<List items="{/EntitySet}" updateFinished="onListUpdateFinished"....>
----- onListUpdateFinished ---
var aItems = oList.getItems();
for (var m = n + 1; m < aItems.length; m++) {
//set a boolean, true if duplicate
var bDuplicate = aItems[m].getText() ==== aItems[n].getText() &&
aItems[m].getDate() === aItems[n].getDate();
//set the visibility of the item to true if it is not a duplicate
aItems[m].setVisible(!bDuplicate)
}
3.) Read the data manually, remove duplicates, and stash it in a JSON model, and bind the table to your JSON model path
oModel.read("/EntitySet", {
success: function(oResponse) {
this._addCommentsToJSONModel(oResponse.results)
}.bind(this)
})
You can stash an array of objects in your JSON model, and then bind the table items to that path
var aDistinctComments = // your logic to get distinct comments
oJSONModel.setProperty("/comments", aDistinctComments)
oList.setModel(oJSONModel);
-----
<List items="{/comments"}....>
4.) Bind your list items to your entity set, iterate over the items, and then remove duplicates from the list. I don't recommend this approach. Removing items manually from lists bound to an entity set can lead to trouble with duplicate IDs.
var oItem = //use your logic to find a duplicate list item
oList.removeItem(oItem)
I recommend first handling this server side in the OData service, and if that's not an option, then use option 1 above. This will give you the desired results and maintain the binding context of your list items. Options 2 and 3 will get you the desired results, but depending on your applicaiton, may make working with the list more difficult.

Here is one approach :
Do not directly bind the list to your oData.
You can create a JSON model which will be the resulting model after removing duplicate items.
Bind the JSON model to the List as such:
var oList = this.getView().byId("feedList");
oList.bindAggregation("items", "pathToJsonArray", template);
(The template is feedlistitem in this case).

How can I do ng-repeat with a firebase Array?

Context
In a Firebase DB I'm storing "events" and "users". Users can have favorite events, to manage them I only store the event's id in the favorite user's DB location. So to grab favorite events informations, I need to firstable grab the event id and then go to the DB events location, to collect all the datas I need.
Problem
I would like to store in an Array all the favorite events informations (each event would be an Object with inside it : "key" : "value"), to use that Array in my HTML view and print the informations. But it doesn't work the way I coded it... :(
// This ref is too grab favorite event id (in my case only 2) in the user DB location
var refUserFavoris = firebase.database().ref().child("users/"+user.uid+"/events/favoris");
$scope.favorisTmp = $firebaseArray(refUserFavoris);
// This shows one array, with two objects (wich are my two user's favorite events) wich include ids
console.log($scope.favorisTmp);
// This is to load the objects and with the foreEach, grab there ids to use them in the next ref call
$scope.favorisTmp.$loaded().then(function()
{
angular.forEach($scope.favorisTmp, function(favoris)
{
// This shows two lines : the id of each object
console.log(favoris.$id);
// Call a new ref to reach the event informations (in a different location of the DB) using the previous id
firebase.database().ref("events/"+favoris.$id).once('value').then(function(snapshot)
{
// Attempt to store events datas for each id I have (in my case, only two)
snapshot.forEach(function(favorisSnap)
{
var favSnap = favorisSnap.val();
// This shows a lot of "undefined" lines, wich I don't want. I would like two objects, with all informations inside
console.log(favSnap.nbPersonne);
// $scope.favorisF is an Array that I would like to use in a ng-repeat to print all datas for each event
// For now this doesn't show anything
$scope.favorisF = favSnap;
});
// If using favSnap out of the previous function, I got a "favSnap" is undifined error
console.log(favSnap);
});
});
});
<ion-item ng-repeat="f in favorisF" class="item-avatar">
{{f.nbPersonne}}
</ion-item>
EDIT 1 :
I tried a new way to have my data, but a new problem came, how to fill an Array inside a loop ? I've tried "push" and "$add" methods, but no one worked. Any ideas ?
var newFav = [];
var user;
user = firebase.auth().currentUser;
var refUserFavoris = firebase.database().ref().child("users/"+user.uid+"/events/favoris");
$scope.favorisTmp = $firebaseArray(refUserFavoris);
$scope.favorisTmp.$loaded().then(function()
{
angular.forEach($scope.favorisTmp, function(favoris)
{
console.log(favoris.$id);
var refFavoris = firebase.database().ref("events/"+favoris.$id);
refFavoris.on('value', function(snap)
{
//This is where I'm trying to fill "newFav" in each steps of the loop
newFav.push(snap.val());
console.log("Scope newFav vaut :", $scope.newFav);
});
});
});

I think you made a typo here.
var refUserFavoris = firebase.database().ref("events/favoris/"+favoris.$id).once('value')

Thanks a lot Abdel, I fixed my problem :
Here is the solution
$scope.newFav = [];
console.log($scope.newFav);
$scope.favorisTmp.$loaded().then(function()
{
angular.forEach($scope.favorisTmp, function(favoris)
{
console.log(favoris.$id);
var refFavoris = firebase.database().ref("events/"+favoris.$id);
refFavoris.on('value', function(snap)
{
$scope.newFav.push(snap.val());
console.log("Scope newFav vaut :", $scope.newFav);
});
});
});

Organize a backbone.js collection?

How does one create a collection (in backbone.js) that is organized by an id. For example I would think it's quite common that collections need to be organized by date, category, keyword, type the list goes on. In my case I am trying to find an elegant way to organize players to team.
I don't think I need a plugin for this, my goal is just to organize the players to be grouped inside a div while using one clean json file so I can have a nice organized list. Again ideally it would be nice to use one json file for this, and structure the HTML similar to how the json itself is structured in terms of nesting, in my example league being the parent of everything, then team being the parent of the players.
I have gone through many backbone tutorials multiple times, and understand the flow and syntax pretty comfortably, but all tutorials work with one collection outputting a simple list in no specific order.
Basically I want to be able to create a clean json array like below. Then turn it into nice organized HTML.
{
"league":
[{
"team":"Lakers",
"players": [
{
"name": "Kobe"
},
{
"name": "Steve"
}
]
},
{
"team":"Heat",
"players": [
{
"name": "LeBron"
},
{
"name": "Mario"
}
]
}]
}
So this json structure is valid but it's not one I have used it's nested a little bit more, so accessing the models requires a little different technique, I am hoping to learn if this kind of array is ideal? Also if so how would I group say Kobe, Steve inside a div with perhaps the class name Lakers whilst obviously separating it from LeBron and Mario keeping those two inside a div with again perhaps a class of Heat.
Another example I could use would be like a actors to movies collection, again is the json format ideal (seems like it to me) here I obviously group actors to their respected movie? I would greatly appreciate some tips on building a clean view or views with a template or templates for outputting this nice and tidy.
{
"movies":
[{
"title":"Prisoners",
"actors": [
{
"name": "Hugh Jackman"
},
{
"name": "Jake Gyllenhaal"
}
]
},
{
"title":"Elysium",
"actors": [
{
"name": "Matt Damon"
},
{
"name": "Jodie Foster"
}
]
}]
}
Again just working with this json data and backbone.js how do I create a maintainable view for this array?
Final Note: I was able to successfully group players to teams using two json files, and assigning a player and id that matched the team id, then looped the team collection with the player collection inside using where to organize it (I am trying to rethink this better). To me this is not taking advantage of backbone, it can get confusing and just seems wrong to me. So again I hope to improve my knowledge here and get better. I would immensely appreciate clear concise information, I really struggle to wrap my head around this topic :)
THANKS!!

Keep your JSON in a Backbone friendly structure, this will mean your models are easily organised once they are placed into the collection.
JSON example
[
{ league : 1, team : 'lakers', player : 'kobe' }
{ league : 1, team : 'lakers', player : 'steve' }
// And so on
]
Consider that most backbone collections are built via a RESTful JSON api this would be easy to fetch directly into a collection and then sorted. The comparator() function on the collection is run each time a model is added to the collection, or when you ask for it to run.
Backbone collection example
var Players = Backbone.Collection.extend({
initialize : function() {
// Grab the JSON from the API
// this.fetching is now a deferred object
this.fetching = this.fetch();
}
// Comparator example one, as a string
comparator : 'team',
// Comparator example two, as a function
comparator : function(model) {
return model.get('team');
}
});
The comparator as a function approach is obviously better suited to more complex sort algorithms, otherwise the comparator as a string approach would be better. Bear in mind that the function approach, though a string can be returned (such as above), -1 or 1 would be better return values to indicate it's sort position.
Comparator example with model comparison
comparator : function(modelA, modelB) {
var teamA = modelA.get('team'),
playerA = modelA.get('player'),
teamB = modelB.get('team'),
playerB = modelB.get('player');
if (teamA < teamB) { // string comparison
return 1;
} else if (playerA < playerB} {
return 1;
} else {
return -1;
}
}
Now whenever a model is added to the collection it is sorted into it's correct location, if using the last example, by team and then by player name.
Simple view example using the collection
var ViewExample = Backbone.View.extend({
el : "#example-container",
render : function() {
var self = this;
// Use the deffered object to make sure models are
// all available in the collection before we render
this.collection.fetching.done(function() {
self.collection.each(function(model) {
self.$el.append('<p>' + model.get('player') + '</p>');
});
});
return this;
}
});
// Create the view and pass in the collection
// that will immediately fetch it's models
var view = new ViewExample({
collection : new Players()
});
Code here is untested

Start by building a working model of your data. Your JSON suggests a hierarchy : a collection of teams that each have a collection of players. Here's a possible implementation :
var Player = Backbone.Model.extend();
var Players = Backbone.Collection.extend({
model: Player
});
var Team = Backbone.Model.extend({
constructor: function(data, opts) {
// I like my subcollections as attributes of the model
// and not on the settable properties
this.players = new Players();
Backbone.Model.call(this, data, _.extend(opts, {parse: true}));
},
parse: function(data) {
// Players are handled in a subcollection
if (_.isArray(data.players))
this.players.reset(data.players);
// They are removed from the model properties
return _.omit(data, 'players');
}
});
var Teams = Backbone.Collection.extend({
model: Team,
parse: function(resp) {
return resp.league;
}
});
Now you can create your root collection. Note that you could also fetch it instead of instantiating it with the data.
// teams list
var teams = new Teams(data, {parse: true});
// for example, to get all players in all teams
var allplayers = _.flatten(teams.map(function(team) {
return team.players.models;
}));
console.log(_.invoke(allplayers, 'get', 'name'));
And a demo : http://jsfiddle.net/8VpFs/
Once you have your structure in place, you can worry about rendering it. Let's imagine you have this (Underscore) template
<ul>
<% _(teams).each(function(team) { %>
<li><strong><%= team.team %></strong>
<ul>
<% _(team.players).each(function(player) { %>
<li><%= player.name %></li>
<% }); %>
</ul>
</li>
<% }); %>
</ul>
You can alter your Team model to output a serialized representation of you model:
var Team = Backbone.Model.extend({
// ... as before
toJSON: function() {
var json = Backbone.Model.prototype.toJSON.call(this);
json.players = this.players.toJSON();
return json;
}
});
and render your template
var tpl = _.template($('#tpl').html());
var html = tpl({
teams: teams.toJSON()
})
$('body').append(html);
This usually would go into a view.
http://jsfiddle.net/8VpFs/1/
With a fetch
var teams = new Teams();
teams.fetch().then(function() {
var tpl = _.template($('#tpl').html());
var html = tpl({
teams: teams.toJSON()
});
$('body').append(html);
});
http://jsfiddle.net/8VpFs/2/

Add a row in Dojo datagrid

Struggling to find a bit of code to easily understand.
How do you add a row and clear all rows in a Dojo datagrid (version 1.4.2). Lets say the data is 2 columns with customerID and address.
I am using
dojo.data.ItemFileWriteStore
to store values in - but again not quite sure how this should be used.
It can't be that hard.
Cheers.

You can get the data store reference from the grid using grid.store, then you can use store.newItem() to create a new item in the store. This new item is added as a new row in the grid. For example, store.newItem({customerID : 1, address : "Somewhere"}).
To clear all the rows, you can either loop all the items in the data store and use deleteItem() to remove all the items, or use the internal function _clearData() in data grid to remove all the rows, or use setStore() to set a new empty store to the grid. I prefer to use a empty store to reset the grid.

The above answers are correct, but you also need to call save() on the write store to "commit" the change. When you save, a widget using the store (datagrid for example) will refresh itself.
Also, newItem() returns the new item you just created so if you don't want to pass an object to newItem just modify its return value, then save() the store.
Pseudo code:
var i = store.newItem({});
store.setValue(i,"newattribute1","new value");
store.setValue(i,"newattribute2","new value 2");
store.save();
Here is the relevant docs for ItemFileWriteStore which tell how to use newItem(), setValue(), and save().
Instead of deleteItem, you should use setStore(new ItemFileWriteStore()), but I suspect there is a memory leak when you do this, be careful. This makes a new blank store to be used with the grid.

I have finish one example about this... the code is here
//First we create the buttons to add/del rows
var addBtn = new dijit.form.Button({
id: "addBtn",
type: "submit",
label: "Add Row"
},
"divAddBtn");//div where the button will load
var delBtn = new dijit.form.Button({
id: "delBtn",
type: "submit",
label: "Delete Selected Rows"
},
"divDelBtn");
//Connect to onClick event of this buttons the respective actions to add/remove rows.
//where grid is the name of the grid var to handle.
dojo.connect(addBtn, "onClick", function(event) {
// set the properties for the new item:
var myNewItem = {
id: grid.rowCount+1,
type: "country",
name: "Fill this country name"
};
// Insert the new item into the store:
// (we use store3 from the example above in this example)
store.newItem(myNewItem);
});
dojo.connect(delBtn, "onClick", function(event) {
// Get all selected items from the Grid:
var items = grid.selection.getSelected();
if (items.length) {
// Iterate through the list of selected items.
// The current item is available in the variable
// "selectedItem" within the following function:
dojo.forEach(items, function(selectedItem) {
if (selectedItem !== null) {
// Delete the item from the data store:
store.deleteItem(selectedItem);
} // end if
}); // end forEach
} // end if
});