I'm making a Grocery list app, which is very similar with the todo list. I have several years of Rails dev experience, but am having trouble figuring out from all the examples what to put into a collection, and what to make a model.
I mocked up the app with Sinatra and Redis as the backend. My goal is to make Sinatra just the simple API and have backbone manage all the view.
Right now, a Grocery list is just a complex ID, which has a Set of string items. So something like:
/lists/asdfasdf34asdf => ["eggs", "bacon", "milk"]
Moving to backbone, would I make the model an "Item" and then the collection would be the "List", or would it be something else?
I guess my routes aren't classic Rest so maybe that's why i'm having trouble sorting out what to do where.
If there's only one grocery list, a Collection of item Models is probably appropriate. Backbone isn't too prescriptive about how things are organized, but you will definitely want to set the url property of each model/collection in a logical fashion. You might do something like this:
var app = {
item: Backbone.Model.extend({
// define an item model to go in the itemCollection
}),
itemCollection: Backbone.Collection.extend({
initialize: function (key) {
this.key = key;
},
model: app.item,
url: function () {
return 'lists/' + this.key + '/items/'
}
})
}
and then instantiate each version of the application along these lines:
var userListKey = 'foobar',
userCollection = new app.itemCollection(foobar);
// proceed with app. Requests for userCollection will now be
// directed to /lists/foobar/items
There are many other ways to do this, but hopefully this is a start.
Related
Background
I have an angular-meteor app and a collection of business objects in mongodb, e.g.:
{ startDate: new Date(2015, 1, 1), duration: 65, value: 36 }
I want to render this data in different views. One of the views is a graph, another is a list of entries.
The list of entries is easy. Just bind the collection to the model:
vm.entries = $scope.meteorCollection(MyData, false);
In the view I would do:
<div ng-repeat="entry in vm.entries">{{entry.startDate}} - ...</div>
But now for the graph. I want to transform each element into a { x, y } object and give the view that, e.g.:
vm.graphPoints = transformData(getDataHere());
The problem is that the data is not fetched here, in angular-meteor is looks like it is fetched when calling the entry in vm.entries in the view. The kicker is that the transformData method, needs to loop through the data and for each item index into other items to calculate the resulting x, y. Hence I cannot use a simple forEach loop (without having access to the other items in some way).
Question
So how can i fetch the data in the controller - transform it - and still have one-way binding (observing) on new data added to the database?
Thanks
Update
The following code works, but I think there could be performance problems with fetching the whole collection each time there is a change.
$scope.$meteorSubscribe("myData").then(function() {
$scope.$meteorAutorun(function() {
var rawData = MyData.find().fetch();
vm.model.myData = transformData(rawData);
});
});
EDIT:
This is the current solution:
$scope.collectionData = $scope.meteorCollection(MyData, false);
$meteor.autorun($scope, function() {
vm.graphPoints = transformData($scope.collectionData.fetch());
});
There is some missing information. do you wan't to have some kind of model object in the client? if that is correct I think you have to do something like this:
$meteor.autorun($scope, function() {
vm.graphPoints = transformData($scope.meteorCollection(MyData, false));
});
How about using the Collection Helper Meteor package to add the function:
https://github.com/dburles/meteor-collection-helpers/
?
I have a question about adding arrays to Firebase using AngularFire. Let's start with a quick example. What I tend to do when my users on the front end create a list is something like this:
angular.module("app", ["firebase"])
.controller("createListCtrl", function($scope, $firebaseArray) {
console.log("controller loaded");
$scope.newList = [];
$scope.addItemToList = function(itemlist) {
console.log(itemlist);
$scope.newList.push({
"item": itemlist,
"done": false
});
}
$scope.sendToDb = function() {
var ref = new Firebase("https://xxxxxx.firebaseio.com");
var list = $firebaseArray(ref);
list.$add({
"list": $scope.newList
}).then(function(ref) {
var id = ref.key();
console.log("added record with id " + id);
console.log(list.$indexFor(id)); // returns location in the array
})
}
Ok all nice and dandy and it all works great but I then I read this article:
https://www.firebase.com/blog/2014-04-28-best-practices-arrays-in-firebase.html
And I heard more people say to avoid arrays and I see the problem with array in Firebase, but what is the alternative, the article says this structure:
{foo: {counter: 1}, bar: {counter: 1}, baz: {counter: 1}};
Is that really a better structure? I think it gets messy and I don't even know how I would achieve this structure starting with something like this:$scope.newList = {};. Is it really a problem doing it with an array. Are arrays really evil in Firebase? Thanks in advance for an explanation or a better alternative.
edit
This is how the list is stored in Firebase, which does not seem very good:
---uniqueID
---list
---0
---done:false
---item:"item1"
---1
---done:false
---item:"item2"
---2
---done:false
---item:"item3"
The $firebaseArray class, which you're already using, provides a mapping between Firebase's ordered collections (which use push ids for their keys) and AngularJS's array (which use regular arrays).
So in your controller's constructor instead of creating a local array for itemList, create a two-way synchronized $firebaseArray:
$scope.newList = $firebaseArray(new Firebase("https://xxxxxx.firebaseio.com"));
The blog post you're referring to served as the basis for quite a few changes to AngularFire since then. I highly recommend that you work through the AngularFire development guide. It will take at most a few hours and will answer many more questions than just this one (which is covered in the section on synchronized arrays).
Update
Thanks for the update. I now get what you're trying to do. So you initially want to keep the list of items client-side only, and then all at once save it to Firebase.
In that case, I'd write sendToDb like this:
$scope.sendToDb = function () {
var ref = new Firebase("https://xxxxxx.firebaseio.com");
var listRef = ref.push();
$scope.newList.forEach(function(item) {
var itemRef = listRef.push({ item: item.item, done: item.done });
console.log('Added item with key: '+itemRef.key());
});
}
This uses the regular Firebase JavaScript SDK. But since AngularFire is built on top of that, they will co-exist without problems.
So instead of pushing the array in one go, I simply loop over the items in it and push each of them.
Working fiddle here: https://jsfiddle.net/frankvanpuffelen/vnh5dbwq/11/
I am trying to reset a backbone collection with an array of models. It gets reset but the model structure is changed (nested one level).
Here is a detailed explanation:
Model
var SeatModel = Backbone.Model.extend({
defaults:{
},
initialize:function () {
console.log('Model initialized');
}
});
Collection
var myCollection = Backbone.Collection.extend({
url:"",
parse:function (data) {
},
initialize:function () {
console.log('Collection initialized');
}
});
Now, I am executing some logic in a web worker, which generates an array of models. The size of the array varies depending on the url I hit.
When the array is ready, I reset the data in the collection using something like:
(Before this, I have instantiated the collection and set it in an service object)
worker.onmessage = function(e) {
newDataForCollection = e.data;
//update the collection
service.get("myCollection").reset(newDataForCollection);
};
After getting reset, the structure of the collection gets changed to something like:
models: Array[3154]
[0...99]
0:g.Model
attributes:
attributes:
price: "12"
Whereas it should be like:
models: Array[3154]
[0...99]
0:g.Model
attributes:
price: "12"
Also the number of models in the array gets reduced. (Should have been around 6100 in this case).
I am unable to figure out, what causes the internal structure to get nested by one level on invoking reset on the collection.
Updated Post
Figured it out. We cannot send objects with functions in post message, so the models in the array just have the attributes and no functions. Related Passing objects to a web worker
Figured it out. We cannot send objects with functions in post message, so the models in the array just have the attributes and no functions. This was related to issue Passing objects to a web worker
var items=[{"endsAt": "2013-05-26T07:00:00Z","id": 1,"name": "Niuniu1"},
{"endsAt": "2013-05-26T07:00:00Z","id": 2,"name": "Niuniu2"}]
ItemModel=Backbone.Model.extend({});
ItemCollection=Backbone.Collection.extend({
model:ItemModel,
url: '...',
parse: function(response) {
return response.items;
}
})
If I have a series of data like items, when I build model, for each model, it's endAt will be "2013-05-26T07:00:00Z". Where can I modify the model or data process so it will actually be "2013-05-26"?
I could do a foreach loop inside collection to process the date, but I'm wondering if there is a better pracitce like to do a parse inside the model?
Thanks!
The practice I use is the one you said you've thought about - implementing a custom parse on the model. As the documentation states, it will be called for you after a sync. See here: http://backbonejs.org/#Model-parse
ItemModel = Backbone.Model.extend({
parse: function(response,options) {
//perform your work on 'response',
// return the attributes this model should have.
};
})
As far as I know, you have 2 options here
Implement a custom parse method inside your model
Implement the initialize method inside your model
Both of them don't have any problems, I did 2 ways in several projects, and they work well
I am new to Backbone-relational, I am not sure what is the right way to use HasMany.
I have a Parent model which have many children (by "many" I mean thousands of children). In order to avoid performance issue, I query children by their foreign key: /child/?parent=1, instead of create a huge list of child_ids in Parent. But seems this is not the way Backbone-relational work.
So I am wondering what is the right way to handle this.
1, Change my json api to include list of child id in parent, then send thousands of ids as Backbone-relational recommend:
url = function(models) {
return '/child/' + ( models ? 'set/' + _.pluck( models, 'id' ).join(';') + '/' : '');
}
// this will end up with a really long url: /child/set/1;2;3;4;...;9998;9999
2, override many method in Backbone-relational, let it handle this situation. My first thought is :
relations: [{
collectionOptions: function(model){
// I am not sure if I should use `this` to access my relation object
var relation = this;
return {
model: relation.relatedModel,
url: function(){
return relation.relatedModel.urlRoot + '?' + relation.collectionKey + '=' + model.id;
}
}
}
}]
// This seems work, but it can not be inherent by other model
// And in this case parent will have am empty children list at beginning.
// So parent.fetchRelated() won't fetch anything, I need call this url my self.
3, Only use Backbone-relational as a Store, then use Collection to manage relations.
4, Some other magic way or pattern or backbone framework
Thanks for help.
Here's the solution that I have going on my current project. Note that Project hasMany comments, events, files, and videos. Those relations and their reverse relations are defined on those models:
Entities.Project = Backbone.RelationalModel.extend({
updateRelation: function(relation) {
var id = this.get('id'),
collection = this.get(relation);
return collection.fetch({ data: $.param({ project_id: id }) });
}
});
I have the REST endpoint configured to take parameters that act as successive "WHERE" clauses. So project.updateRelation('comments') will send a request to /comments?project_id=4 I have some further logic on the server-side to filter out stuff the user has no right to see. (Laravel back-end, btw)