I'm testing Localstorage of Backbone with the following code. After saving the model, it's supposed to create an id and also a cid that is accessible at Model.cid. It's logging the id in the console (see below), but not the cid. Here's a fiddle that recreates the problem http://jsfiddle.net/mjmitche/haE9K/2/
Can anyone see what I'm doing wrong?
// Model Creation with defaults
var Todo = Backbone.Model.extend({
localStorage: new Backbone.LocalStorage("todos"),
defaults: {
title:'new todo...',
description:'missing...',
done:false
}
});
var myTodo = new Todo({});
console.log("Before save id:"+myTodo.get('id')); // Unique Id from Server
console.log("Before save cid:"+myTodo.cid); // Client side id
myTodo.save();
console.log(myTodo.get('title'));
console.log("After save id:"+myTodo.get('id'));
console.log("After save cid:"+myTodo.cid);
Console results
Before save id:undefined app.js:16
Before save cid:c0 app.js:17
new todo... app.js:20
After save id:99bc7f4c-8837-39f4-91e9-90760d8ee8cd app.js:21
After save cid:c0 app.js:22
The cid is created when the model is created and never change then. See the docs:
A special property of models, the cid or client id is a unique
identifier automatically assigned to all models when they're first
created
Lets take a look in the constructing function of Backbone.Model:
var Model = Backbone.Model = function(attributes, options) {
.
.
.
this.cid = _.uniqueId('c');
.
.
.
};
As you can see, the cid is created there using underscores uniqueId method.
Related
i want to create a registration form that will be in batch with a continuation button, getting the id of the entry will help me to call the save method.
I want to immediately get the primary key of a new Entry Created using BreezeJS, Pls i need help on this.
Thanks
Not entirely sure I understand your question, but it sounds like you want to get the id of a newly saved record immediately after the save. If so then the answer below applies.
When the save promise resolves it returns both the list of saved entities as well as a keyMappings array for any entities whose ids changed as a result of the save. i.e. a mapping from temporary to real ids. i.e. (Documented here: http://www.breezejs.com/sites/all/apidocs/classes/EntityManager.html#method_saveChanges)
myEntityManager.saveChanges().then(function (saveResult) {
// entities is an array of entities that were just saved.
var entitites = saveResult.entities;
var keyMappings = saveResult.keyMappings;
keyMappings.forEach(function(km) {
var tempId = km.tempValue;
var newId = km.realValue;
});
});
On the other hand if you have an entity and you just want its 'key' you can use the EntityAspect.getKey method. (see http://www.breezejs.com/sites/all/apidocs/classes/EntityAspect.html#method_getKey)
// assume order is an order entity attached to an EntityManager.
var entityKey = order.entityAspect.getKey();
According to the Angularfire docs, when working with an object returned through $asObject(), you can set priority for said object by defining a $priority property on the object and then using $save().
My code works great, but $priority isn't doing anything. Here's some code with complete explanations in the comments:
app.factory('MyService', function($rootScope, $firebase) {
// The complete Firebase url
var ref = *obfuscated*;
// Returning the dataset as an object containing objects
var data = $firebase(ref).$asObject;
// This object is what's returned by MyService
var Data = {
// Method to create a new object within the data set,
// keyed by myId. Attempting to set priority for the
// record via $priority. returnData.uid is a valid string.
create: function(returnData, myId) {
data[myId] = {
myId: myId,
$priority: returnData.uid
};
// No need to explain the stuff between here and the
// $rootScope listener below, just added for context
data.$save().then(function() {
setMyId(myId);
});
},
findByMyId: function(myId) {
if (myId) {
return data[myId];
}
}
};
function setMyId(myId) {
$rootScope.myId = User.findByMyId(myId);
}
// This event listener works fine, fires
// at user login and returns data
$rootScope.$on('$firebaseSimpleLogin:login', function(e, returnData) {
// returnData.uid has the correct value - this
// function should return the object(aka record) with
// a priority matching returnData.uid
var query = $firebase(ref.startAt(returnData.uid).endAt(returnData.uid)).$asObject();
// console shows an object with the normal $firebase
// properties, but no records. If I define query without
// limiting the set ($firebase(ref).$asObject()), it returns
// the full set just fine. The priority on all records is still
// null.
console.log(query);
query.$loaded(function() {
setData(query.myId);
});
});
return Data;
});
Yes, I'm following Thinkster.io's tutorial and I'm in Chapter 7. No, this is not a duplicate of the other questions about that chapter, I already found my way around the pre-Angularfire 0.8 code present in their examples, just can't set $priority, and I've spent about 5 hours so far trying to find a solution through my own efforts and on the web.
Any takers?
When viewed in the light of how JavaScript works with objects (i.e. unordered), how JSON handles objects (i.e. unordered), and in light of the expectation that AngularFire's $asObject() method is intended for storing key/value pairs, and singular records that are not used as a collection, this starts to make some sense.
Internally, the synchronize'd object's $save method calls Firebase's setWithPriority. In set or setWithPriority calls, the child nodes are replaced. Any meta data like priorities on those children are replaced.
In AngularFire, $asArray is intended to handle ordered collections, and provides the ability to set $priority on child nodes (only one level deep, of course, as it treats its children as singular records that are not themselves collections).
Since, in your case, you want to work with fixed keys rather than push ids, you'll probably want to override the $add method using $extendFactory and do something like the following:
angular.module(MY_APP).factory('FixedKeysFactory', function($FirebaseArray, $firebaseUtils) {
return $FirebaseArray.$extendFactory({
$add: function(data) {
this._assertNotDestroyed('$add');
if( angular.isObject(data) && typeof data.$id === 'string' ) {
return this.$inst().$set(data.$id, $firebaseUtils.toJSON(data));
}
else {
return this.$inst().$push($firebaseUtils.toJSON(data));
}
}
});
});
You could then pass this into your $firebase instance in place of the default factory:
var list = $firebase(ref, {arrayFactory: FixedKeysFactory}).$asArray();
A simpler but less awesomatic™ solution would be to manually add your objects to the array, manually giving them a $id, then call $save:
var list = $firebase(ref).$asArray();
var i = list.length;
list.push({ foo: 'bar', $id: 'kato' });
list.$save(i);
Some notes on the future: It will soon be possible to use any field as sort criteria and there will be no need to set priorities (yay!). It will probably be possible to set your own $id before calling $add on a synchronized array in AngularFire as soon as I clear that with the other devs (like the 0.8.3 release).
I am building my first Angular app with a list of product specifications such as "Brand name" etc. The finished app will be connected to an MSSQL db.
I have a list with the saved Specifications and when I click one of them I want the following to happen:
Show Edit Specification Tab
Pass the parameter SpecificationId
Perform an http GET with current Specification Id
I set up a plunker with the app in its basic state:
http://embed.plnkr.co/4F8LMwMorZEF0a42SzTJ/
As you are already sending your id you just need to get it within your method:
Update your controller like this:
app.controller('TabController', function ($scope) { // use $scope here
and set the id in the $scope.spec object like below:
this.setTab = function (selectedTab, specId) { // get the id in the args here
this.tab = selectedTab;
$scope.spec = {id : specId}; // set the id in here
console.log($scope.spec.id);
};
and then you can bind the id value in the markup as this:
The current Specification ID is: <strong>{{spec.id}}</strong>
Updated plunkr demo.
var manifest = Alloy.Collections.manifest;
function submit(){
list_view.open();
manifest.fetch();
var model = Alloy.createModel('manifest', {
bill: //(need to be an incremented value),
Num_of_elements: $.items.value
});
manifest.add(model);
model.save();
}
so i have this function the when clicked it will save info the the data base, or model not to sure what the differante is yet. i want to be able to get that "Num_of_elements" value from the model at a latter time, how would i go about this. model.execute(sql query)?
If you have the bill number you can just do this, using the where function of backbone collections:
var manifest = Alloy.Collections.manifest;
var manifest = manifest.where({
bill : // your bill number
})[0]; // Get the first one returned
I have been trying out backbone.js and have been stymied when I create a new model object then call model.save(). I am expecting the backbone.js default behavior to update the model object with the id from the database but it is not. Is this not supposed to happen? I have verified that I am getting a post with the attributes in json format. My server saves the json to a table and then returns the json with a new id field to backbone.js. Is this correct? Should my server return the entire new object or just the id or what?
//contents of the POST from backbone.js
{ "text":"this is a test" }
//reply from my server
{ id:"15", text:"this is a test" }
My sample code is below
var SQLRow = Backbone.Model.extend({
table:"",
urlRoot:'db',
url:function () {
return "/" + this.urlRoot + "?table=" + this.table +
"&id=" + this.attributes.id;
}
});
var Xtra = SQLRow.extend ({
table:'Xtra'
});
var row = new Xtra({
text: "this is a test"
});
alert(row.url());
row.save()
alert("row:" + row.get("id"));
Tough to tell from your post. Two ideas :
1) the response from the server isn't successful What does your save call return ?
2) Your "id" attribute is named something other than ID. To account for the different name add the following to your model :
idAttribute : "MyModelsID",
EDIT
You're likely facing a timing issue, where the alert fires before the ID has returned. Instead of your last two lines try this :
row.save( null,
{
success : function(model, response) { alert(model.get('id'); }
}
);
ALTERNATIVE
As #mu_is_too_short mentioned, another way is to listen for the change even on the model and respond to the event. (i was just trying to keep the answer as close to your code as possible). But something like the following pseudo code should get you started...
var myView = Backbone.View.extend({
....
initialize : function () {
this.collection.bind('change', this.SOME_LISTENING_FUNC );
}
});
OR, if you're in a collection/view-less world something like this creates a listenr ...
row.on('change', function() { /* do stuff */ }, this);
This answer is based on one comment of Cjolly in the answer above.
It is essential for making the Backbone.Model.save([attributes],[options]) successful in assiging the model with the newly generated model's id from the server, that the server returns the model's id in a JSON string like this { "id" : <the id> }. (note it is "id" and not id).
In essence backbone rightly expects a JSON string and in contrast to how objects may be defined in Javascript without quoted keys, JSON requires the object keys to be quoted (see JSON Spec - does the key have to be surrounded with quotes?)
Since according to Cjolly's comment this has been the essential problem, I want to hightlight this solution in an second answer. Partially because I was hit by the very same problem and only by reading througth the comments I was able to receive the insight.
I've faced the same issue and what I've found is that my validate function of the saved model actually invalidates the model returned from the back end. That's why my fields were not updated properly.
Maybe its a little outtimed, but today I had the same missing id.
It turns out, that the server just sends a Header 'Location' with a redirect containing the new id, but dosen't return the persisted object.
Adding the object to the response was the solution.
It seems, that not returning the object is standard behavier with Roo(Spring) generated Json-Controllers.