I have a grid with remote data (php/mysql/json) and use a form to insert records or to edit this data.
I use the api configuration of the proxy/store. I use MVC architecture.
So, all very simple (in pseudo code):
get selected model form grid or create model
frm.loadRecord()
frm.updateRecord()
frm.getRecord().save()
and all works fine, but I noticed in the browser console that after the POST (works fine, calls either the url configured with create or the url configured with update), the store calls (GET) the url configured with retrieve twice. These calls are identical.
So functionally all works fine and I could ignore it, but now I've noticed I want it fixed.
Can anyone help me where to look? Thanks in advance.
Details:
It's all really basic:
In the controller of the gridpanel:
updateRow: function (gridpanel) {
var sm = gridpanel.getSelectionModel();
var record = sm.getLastSelected();
this.showForm(record);
}
and
showForm: function (record) {
...
formpanel.show();
var frm = formpanel.getForm();
frm.loadRecord(record);
}
In the controller of the formpanel:
submit: function(frm) {
frm.updateRecord();
frm.getRecord().save();
}
When I remove the save action the GET requests aren't called, so this seems to trigger them.
In the store:
api: {
create: '../php/api/customers.php?request=create',
read: '../php/api/customers.php?request=retrieve&scope=summary',
update: '../php/api/customers.php?request=update',
destroy: '../php/api/customers.php?request=delete'
}
The screenshot:
Related
I have the following publisher and subscriber code.
It works for the first time when the app starts, but when I try to insert data directly into the Mongo database, it will not automatically update the user screen or I don't see the alert popping.
Am I missing something?
Publish
Meteor.publish('userConnections', function(){
if(!this.userId){
return;
}
return Connections.find({userId: this.userId});
})
Subscribe
$scope.$meteorSubscribe('userConnections').then(function () {
var userContacts = $scope.$meteorCollection(Connections);
alert("subscriber userConnections is called");
if (userContacts && userContacts[0]) {
....
}
}, false);
First off, if you are not using angular-meteor 1.3 you should be. The API has changed a lot. $meteorSubscribe has been deprecated!
To directly answer your question, $meteorSubscribe is a promise that gets resolved (only once) when the subscription is ready. So, it will only ever be called once. If you look at the documentation for subscribe you'll see how to make the binding "reactive", by assigning it to a scope variable. In your case it would be something like:
$scope.userContacts = $scope.$meteorCollection(Connections);
Doing it this way, when the collection gets updated, the $scope.userContacts should get updated as well.
I have been given a Project which is written entirely in Backbone.js, which I am supposed to change according to our specific needs. I have been studying Backbone.js for the past 2 weeks. I have changed the basic skeleton UI and a few of the features as needed. However I am trying to understand the flow of the code so that I can make further changes.
Specifically, I am trying to search some content on Youtube. I have a controller which uses a collection to specify the url and parse and return the response. The code is vast and I get lost where to look into after I get the response. I tried to look into views but it only has a div element set. Could someone help me to proceed. I wont be able to share the code here, but a general idea of where to look into might be useful.
Code Snippet
define([
'models/youtubeModelForSearch',
'coretv/config',
'libs/temp/pagedcollection',
'coretv/coretv'
],function( youtubeModelForSearch, Config, PagedCollection, CoreTV ) {
"use strict";
return PagedCollection.extend({
model: youtubeModelForSearch,
initialize: function() {
this.url = 'http://gdata.youtube.com/feeds/api/videos/?v=2&alt=json&max-results=20';
},
fetch: function(options) {
if (options === undefined) options = {};
if (options.data === undefined) options.data = {};
//options.data.cmdc = Config.getCMDCHost();
//CoreTV.applyAccessToken(options);
PagedCollection.prototype.fetch.call(this, options);
},
parse: function(response) {
var temp = response.feed
/*temp["total"] = 20;
temp["start"] = 0;
temp["count"] = 10; */
console.log(temp);
return temp.entry;
},
inputChangeFetch: function(query) {
this.resetAll();
if(query) {
this.options.data.q = query;
// this.options.data.region = Config.api.region;
//this.options.data.catalogueId = Config.api.catalogueId;
this.setPosition(0);
}
}
});
});
Let's assume your collection endpoint is correctly set and working. When you want to get the data from the server you can call .fetch() on you collection.
When you do this, it will trigger an request event. Your views or anybody else can listen to it to perform any action.
When the data arrives from the server, your parse function is called, it is set using set or reset, depending the options you passed along fetch(). This will trigger any event related to the set/reset (see the documentation). During set/reset, the data retrieved from your server will be parsed using parse (you can skip it, passing { parse: false }.
Right after that, if you passed any success callback to your fetch, it will be called with (collection, response, options) as parameters.
And, finally, it will trigger a sync event.
If your server does not respond, it will trigger an error event instead of all this.
Hope, I've helped.
OK, I'm stuck on what should be a basic task in ExtJs. I'm writing a simple login script that sends a user name and password combination to a RESTful web service and receives a GUID if the credentials are correct.
My question is, do I use a Model Proxy or a Store Proxy?
To my understanding, Models represent a single record, whereas Stores are for handling sets of data containing more than one record. If this is correct then it would seem that a Model proxy is the way to go.
Following Sencha's documentation at http://docs.sencha.com/extjs/4.2.1/#!/api/Ext.data.Model the code would look something like this:
Ext.define('AuthenticationModel', {
extend: 'Ext.data.Model',
fields: ['username', 'password'],
proxy: {
type: 'rest',
url : '/authentication'
}
});
//get a reference to the authentication model class
var AuthenticationModel = Ext.ModelManager.getModel('AuthenticationModel');
So far everything is OK, until the next step:
//Use the configured RestProxy to make a GET request
AuthenticationModel.load('???', {
success: function(session) {
console.log('Login successful');
}
});
The load() method for the Model class is a static call expecting a single unique identifier. Logins typically depend upon two factors, username and password.
So it appears Store proxies are the only way to validate someone's username and password credential combination in ExtJS. Can someone verify and explain? Any help to understand this would be greatly appreciated.
You just need to know the following:
The store will use it's own proxy if you configured one for this
instance and if not he takes the proxy from the model.
So you can easily go with two proxy configurations to enable the multi-CRUD operations on the store and the single-CRUD operations on the Models. Note the the static load method of the Model expects the model id because it is supposed to load a model by just one Id (yes, composite keys are not supported). You will also have to fetch the model instance in the callback (As you did).
Back to your Username/password problem
You may apply your session Model with a custom 'loadSession' method
loadSession: function(username,password, config) {
config = Ext.apply({}, config);
config = Ext.applyIf(config, {
action: 'read',
username: username,
password: password
});
var operation = new Ext.data.Operation(config),
scope = config.scope || this,
callback;
callback = function(operation) {
var record = null,
success = operation.wasSuccessful();
if (success) {
record = operation.getRecords()[0];
// If the server didn't set the id, do it here
if (!record.hasId()) {
record.setId(username); // take care to apply the write ID here!!!
}
Ext.callback(config.success, scope, [record, operation]);
} else {
Ext.callback(config.failure, scope, [record, operation]);
}
Ext.callback(config.callback, scope, [record, operation, success]);
};
this.getProxy().read(operation, callback, this);
}
Now call this instead of load.
I found it in the documentation of sencha App Architecture Part 2
Use proxies for models:
It is generally good practice to do this as it allows you to load and
save instances of this model without needing a store. Also, when
multiple stores use this same model, you don’t have to redefine your
proxy on each one of them.
Use proxies for stores:
In Ext JS 4, multiple stores can use the same data model, even if the
stores will load their data from different sources. In our example,
the Station model will be used by the SearchResults and the Stations
store, both loading the data from a different location. One returns
search results, the other returns the user’s favorite stations. To
achieve this, one of our stores will need to override the proxy
defined on the model.
I am using Angular js to show loading screen. It works for all the REST services call except REST service to download the file. I understand why it is not working because for download I am not making any service call using $resource; instead of that I am using normal approach to download the file therefore Angular js code doesn't have any control on start/finish the service request. I tried to use $resource to hit this REST service however I am getting the data from this service and in this case loading screen was working fine however not sure how to use this data to display to user to download in angular way. Following are required details. Please help.
Approach 1 using iframe approach:
/*Download file */
scope.downloadFile = function (fileId) {
//Show loading screen. (Somehow it is not working)
scope.loadingProjectFiles=true;
var fileDownloadURL = "/api/files/" + fileId + "/download";
downloadURL(fileDownloadURL);
//Hide loading screen
scope.loadingProjectFiles=false;
};
var $idown; // Keep it outside of the function, so it's initialized once.
var downloadURL = function (url) {
if ($idown) {
$idown.attr('src', url);
} else {
$idown = $('<iframe>', { id: 'idown', src: url }).hide().appendTo('body');
}
};
Approach 2 using $resource (Not sure how to display data on screen to download)
/*Download file */
scope.downloadFile = function (fileId) {
//Show loading screen (Here loading screen works).
scope.loadingProjectFiles=true;
//File download object
var fileDownloadObj = new DownloadFile();
//Make server call to create new File
fileDownloadObj.$get({ fileid: fileid }, function (response) {
//Q? How to use the response data to display on UI as download popup
//Hide loading screen
scope.loadingProjectFiles=false;
});
};
This is the correct pattern with the $resource service:
scope.downloadFile = function (fileId) {
//Show loading screen (Here loading screen works).
scope.loadingProjectFiles=true;
var FileResource = $resource('/api/files/:idParam', {idParam:'#id'});
//Make server call to retrieve a file
var yourFile = FileResource.$get({ id: fileId }, function () {
//Now (inside this callback) the response data is loaded inside the yourFile variable
//I know it's an ugly pattern but that's what $resource is about...
DoSomethingWithYourFile(yourFile);
//Hide loading screen
scope.loadingProjectFiles=false;
});
};
I agree with you that this is a weird pattern and is different of other APIs where the downloaded data is assigned to a parameter in a callback function, hence your confusion.
Pay attention to the names and the cases of the parameters, and look that there're two mappings involved here, one between the caller to the $resource object and the object itself, and another between this object and the url that it contructs for downloading the actual data.
Here are some idea's for the second approach, you could present the user with a link after the download has happened:
With a "data url". Probably not a good idea for large files.
With a URL like "filesystem:mydownload.zip" You'd first have to save the file with the filesystem API. You can find some inspiration on html5rocks
I'm trying to get the backbone.js DELETE request to fire, but don't see any requests being made in my console.
I have collection model like so:
var Model = Backbone.Model.extend(
{
urlRoot: '/test',
defaults:{}
});
var TableList = Backbone.Collection.extend(
{
url: '/test',
model: Model
});
In my view I'm running this:
this.model.destroy();
Everything seems to be running fine, I can see output coming from the remove function that calls the destroy so I know it's getting there plus it also successfully runs an unrender method that I have. Can't see any requests being made to the sever though?
If I am not mistaken, you have to have an id property on your model to ensure that it hits the correct url. IE if your model was...
var Model = Backbone.Model.extend({
url: '/some/url'
});
var model = new Model({
id: 1
});
model.destroy(); // I THINK it will now try and DELETE to /some/url/1
Without an id it doesn't know how to build the url correctly, typically you'd fetch the model, or create a new one and save it, then you'd have a Url...
See if that helps!
I found the issue to my problem, thought not a solution yet. I'm not sure this is a bug with backbone or not, but I'm using ajaxSetup and ajaxPrefilter. I tried commenting it out and it worked. I narrowed it down to the ajaxSetup method and the specifically the use of the data parameter to preset some values.
Have you tried using success and error callbacks?
this.model.destroy({
success : _.bind(function(model, response) {
...some code
}, this),
error : _.bind(function(model, response) {
...some code
}, this);
});
Might be instructive if you're not seeing a DELETE request.