Knockoutjs templatefiles and localized resx files - javascript

Experimenting with building a SPA app on top of Web API I have come across a problem.
In my project i use Resource.resx files to localize the information displayed.
This is not problem when I create views in .cshtml format, but when I use Knockout templates i get a problem since they are .html and I can no longer access the Resource.resx directly.
I'v considered a few options, including, sending the localized strings together with the model from Web API, creating javascript variables in the .cshtml file and accessing them in the .html and creating a javascript localization file(that either contain constants, or get the values from the .resx ).
Anyone got any good ideas on how to work around this?
Edit:
Ok, the two most viable solutions that I can think of is to print the localized strings in the .cshtml file, like this:
#functions{
public string LocalizedString()
{
return Resource.MyLocalizedString;
}
}
<input id="LocalizedString" type="hidden" value="#LocalizedString()" />
and then get the value using jquery and the id of the input
$("#LocalizedString").val()
so I can populate a localized.js file that i can reference troughout the application.
The other option is to create a wep api service that serves a json list of the strings that i need in my application.
public HttpResponseMessage Get()
{
var localString = new Dictionary<string, string> {
{"FullName", Resource.ACC_FullName},
{"LastName", Resource.ACC_LastName},
{"FirstName", Resource.ACC_FirstName}
};
return Request.CreateResponse(HttpStatusCode.OK, localString);
}
witch would return this JSON
{
fullName: "Fullt navn",
lastName: "Etternavn",
firstName: "Fornavn"
}
This could then be stored in localstorage (I know the inital question was knockout related, and this code is angularjs, but i know you can do it in a similar matter with knockout)
gets(): void {
this.http({ method: 'GET', url: '/api/locals' }).
success(function (data, status, headers, config) {
angular.forEach(data, function (value, key) {
localStorage.setItem(key, value);
});
}).
error(function (data, status, headers, config) {
this.$log.warn(data, status, headers, config);
});
}
witch can then be used on the pages using
localStorage.getItem('Key')
EDIT: in the case of AngularJS you can just utlilize $http inbuilt cache, pretty smart.
The first solution will probably make the variables availabe in the DOM faster, atleast they'll be there when the scrips execute, but I don't like the idea of cluttering my html with stuff that's not really supposed to be there.
The other solution cleans up the html, but i'd have to make a api call to get the values, and the values would not be availabe untill that call was returned. witch means I'd probably need to delay the execution of scripts that rely on the values beeing there until it's done. But the response isn't going to be very large, we are talking maybe 50-100 strings in total (for my site atleast).
Now, I haven't implemented any of these solutions myself yet, and I don't know if they are any good. So if anyone got any comments or ideas i'd like to hear them.

I had a similar problem. Since I have no experience with Knockout.js I am not sure if it helps you. I have a string named Test in my resource file and I am able to have it shown on the front end using the following line of code in my cshtml:
#Html.Raw(WmsWebMvcProto.Properties.Resources.Test)

Related

How to load multiple files with Queue.js and D3.js?

Situation
I am trying to load multiple xml files (located on server) without the need to declare the name of the files hard coded. For this I am trying to use the d3.queue library https://github.com/d3/d3-queue.
I have implemented the xml to force layout to my own needs (https://bl.ocks.org/mbostock/1080941), but there is one crucial flaw namely I need to manually type in the name of the xml file that I want to load...
Reproduce
Given (adjusted example from http://learnjsdata.com/read_data.html) :
queue()
.defer(d3.xml, "/mappings/Customer.hbm.xml")
.defer(d3.xml, "/mappings/Actor.hbm.xml")
.await(analyze);
function analyze(error, Customer, Actor) {
if(error) { console.log(error); }
// do stuff with Customer data, do stuff with Actor data
}
And given my implementation of the processing of an xml:
d3.xml("mappings/Customer.hbm.xml","application/xml", function(error,xml){
if (error) throw error;
// do stuff with the data retrieved from Customer.hbm.xml
});
Question
How do I combine above two snippets in such a way that I dont have to write the locations of the xml hard coded and pass all the parameters to the analyze function? Any nudge in the right direction would be much appreciated.
In psuedocode I have tried to code something like the following (but I cant get it to work):
function to get all names of the xmls from the mappings folder (probably with node.js fs.readdir or fs.readdirSync methods, but I am unsure of how that would work exactly)
for each xml .defer(d3.xml, nameofxml)
pass all the found names as parameters to the analyze function
In Java I would have chosen to do this with a var...args but I dont know how to do it in JS.
There's really two parts to this question:
How do I get a list of server-side files to client-side JavaScript?
Short answer is you don't without having a server-side api that can return that list. Depending on what backend you are using, you write a method that returns a JSON array of the files in your target directory. You call this first, get the response and then process them all with queue:
d3.json('/get/list/of/xml/files', function(error, fileArray){
var q = d3.queue();
fileArray.forEach(function(d){
q = q.defer(d3.xml, d);
});
q.await(analyze);
});
How do a process a variable number of arguments in JavaScript?
This is actually very well supported in JavaScript.
function analyze(error) {
if(error) { console.log(error); }
// skip 0 it's error variable
for (i = 1; i < arguments.length; i++) {
var xml = arguments[i];
...
}
}

Converting PHP object to JSON object using only Javascript

I am making a mobile app with Phonegap and using Wordpress as a backend. I am using Advanced Custom Fields with a Google Maps post field which returns a PHP object to the app using JSON API. My Wordpress backend sends a normal JSON object to the app, but inside that object is where a stringified PHP object is returned.
I need to convert the PHP object to a JSON object somehow on the client side(the app which is not in Wordpress). I have looked at other answers that say to use json_encode for this but my problem is that the app is just HTML/Javascript and no PHP. Is there a way to use PHP code in the middle of a Javascript function to do this? Or would it be better to change the backend so that it returns a JSON object instead of a PHP object in the first place? If so, how do I do that?
My experience in PHP is still somewhat limited so any help is appreciated.
edit: To clarify a bit more, I am using Wordpress on a separate domain from my Phonegap app and only using the JSON API plugin on the Wordpress end. I am then using jQuery Ajax calls to retrieve data from the Wordpress backend.
Also the returned PHP object looks like this: a:3:{s:7:\"address\";s:48:\"8915 W 159th St, Orland Hills, IL, United States\";s:3:\"lat\";s:17:\"41.60111599999999\";s:3:\"lng\";s:11:\"-87.8364575\";}
Another way I just thought of as well, would it be possible to just leave it as a PHP object and still read out the values from it somehow? I don't NEED it to be a JSON array, I just need a way to read the individual elements in the array in one way or another.
Here is also a tiny snippet of the JSON returned to clarify what I'm talking about.
"custom_fields": {
"location": [
"a:3:{s:7:\"address\";s:48:\"8915 W 159th St, Orland Hills, IL, United States\";s:3:\"lat\";s:17:\"41.60111599999999\";s:3:\"lng\";s:11:\"-87.8364575\";}"
]
}
That of course isn't the entire JSON object but it gives you an idea of what I'm dealing with.
I know you have a solution that works on the front end, but I still think it'd be better to fix this on the server.
Based on our conversation in the comments, I've had a closer look the code in the WordPress forum. The problem seems to be that the location field is an array of strings, not just a string. maybe_unserialize (and is_serialized, which it uses) don't handle arrays. Here's the updated code, which you should be able to drop into your theme's functions.php. I did a quick test, and it works for me.
class unserialize_php_arrays_before_sending_json {
function __construct() {
add_action( 'json_api_import_wp_post',
array( $this, 'json_api_import_wp_post' ),
10,
2 );
}
function json_api_import_wp_post( $JSON_API_Post, $wp_post ) {
foreach ( $JSON_API_Post->custom_fields as $key => $custom_field ) {
if (is_array($custom_field)) {
$unserialized_array = array();
foreach($custom_field as $field_key => $field_value) {
$unserialized_array[$field_key] = maybe_unserialize( $field_value );
}
$JSON_API_Post->custom_fields->$key = $unserialized_array;
}
else {
$JSON_API_Post->custom_fields->$key = maybe_unserialize( $custom_field );
}
}
}
}
new unserialize_php_arrays_before_sending_json();
If you're using a JSON API to retrieve the data, then why don't you deliver the data in JSON format to your app? Otherwise you seem to remove much of the point of using an API in the first place... You could of course parse that string in JavaScript if you really want to but that's a very ugly and error prone solution.
The JSON API plugin does seem to use JSON:
https://wordpress.org/plugins/json-api/screenshots/
I need to convert the PHP object to a JSON object somehow on the client side(the app which is not in Wordpress).
This bit here leaves me confused. You do not have PHP objects on the client-side, PHP is a back-end technology. What is returned to the client is a string which can be HTML, XML, JSON, plaintext on any other form of encoding.
That said, saying you have an object $obj in PHP, you could pass it to your front-end application creating an end-point retrieve_object.php and in there:
echo json_encode($obj);
So long as that is the only thing your are outputting, you lient-side app can make a request (Eg: AJAX) to retrieve_object.php and get the json object.
BUT , and this is important (!) in doing so you serialize object properties. You will lose any PHP object method. If any object property is an object itself (EG: A DB Connection) then this will be lost too.
Hope this helps!

WebApi Method with single value and AngularJs $http json handling

I am encountering an issue and I ran out of ideas, I need some guidance towards the origin and/or the solution:
Server Side
I added the standard Microsoft Web Api Controller class "ValuesController" which looks like this:
public class ValuesController : ApiController
{
public string Get(int id){ return "value"; }
...
Client Side
In my AngularJS Controller function I have a simple get
$http({method:'GET',url: '/api/values/1'}).success(function(data){
$scope.value =data;
})
The HTML looks like this:
<input type="text" ng-model="value" />
The weird thing(the issue) is that I get: "value" in my input instead of just value (no quotes).
To avoid misunderstandings, I am getting this:
Instead of this:
And of course the questions are: why?? and how do I fix it*?
*hopefully the answer will not be returning an object instead of a simple string :)
I have the impression that this is due to security vulnerabilities in the JSON format. In the documentation of the $http service there is section called JSON Vulnerability Protection that suggests that Angular takes a few precautions to avoid an attack.
They recommend the reading of the following article: Anatomy of a Subtle JSON Vulnerability which as far as I can see delves into a case similar to yours.
Bottom line, I think you will have to return a full JSON object and not just a string. An alternative is to make sure you are getting a JSON object, by doing
$scope.value = JSON.parse(value)
The preferred (Angular provided solution) is
$scope.value = angular.fromJson(data);

Passing objects from NodeJS to client and then into KnockoutJS viewmodel

So thanks to SO I can pass an object from node to the client, but then getting it into a knockout view model is a bit awkward. These are the steps I have so far (I've included links to the relevant lines as they appear in my github project. Thought the context might help.):
Apply JSON.stringify and pass to the jade file
recipeJSON: JSON.stringify(recipe);
Wrap this in a function in a header script that just parses the JSON and returns the result
script
function getRecipeObject() {
var r = '!{recipeJSON}';
return JSON.parse(r);
}
Call this function and pass the result to a view model constructor
self.recipe = ko.observable(new Recipe(getRecipeObject()));
This works but is there a better way?
Question clarification (Edit): I feel step 2 shouldn't be necessary. Is there a way to directly pass the JSON from node to the Recipe() constructor, without the getRecipeObject() acting as an intermediate step? I tried passing recipeJSON in directly like so
self.recipe = ko.observable(JSON.parse('!{recipeJSON}'));
That doesn't work I think because its not a jade template and has no access to the variable.
According to the answer to this question rendering data into scripts is bad practice and I should instead make an XHR call on page load instead.
Edit
I just saw you linked a github repo! So you're already familiar with most of this...you even have an endpoint set up at /recipe/:id/view, so now I'm really confused...what isn't working out for you? Just the last step of deserialization using ko.utils.*?
Sorry about all the exposition -- I thought this was way more rudimentary than it actually was; I hope no offense taken there!
You really don't want to return a script to execute -- instead, treat this as a DTO: an object that just stores data (no behaviors). An example would be:
{
recipeID: 12,
reviewIDs: [42, 12, 55, 31],
rating: 4.2
recipeName: "A super tasty pie!"
}
This object (representation) is a projection -- a simplified version of the full data stored in the database.
The next step is to create an endpoint to access that data on the server. Let's assume you're using Express:
var app = express();
app.get('/recipes/:recipeID', function(req, res) {
var recipeID = req.params.recipeID;
// It would be cool if this existed, huh?
getRecipeAsync(recipeID, function(recipe) {
res.status(200).json(recipe);
});
});
If you send a GET request to your (hypothetical) application (let's say it's https://localhost:8080/recipes/12), you'll get json representing the (admittedly imaginary) recipe with ID 12.
You can accomplish getting the JSON with jQuery (or any other library that makes XHR nice and pretty)
var recipeID = 12;
$.ajax({
url: "/recipes/" + recipeID,
type: "GET"
}).then(function(recipe) {
console.log("Hey! I got the recipe: %O", recipe);
// Note: you might need to use ko.utils.fromJS(recipe) if the returned
// data is JSON that ISN'T deserialized into an object
var recipeObservable = ko.utils.fromJS(recipe);
});
That's about everything you need to know. Obviously, the devil's in the details, but that's basic idea; let me know if that helps!

JQuery Autocomplete GET & JSON array data security concerns

I am learning JQuery with a MVC3 book. I find that Json data is really easy to use, but it may not be safe.
Consider the scenario, say, I got a CRM with senstive customer infomation. Ajax returns Json array as search results. The search textbox ajax autocomplete also return Json array of senstive keywords from database. etc...They all use GET method.
However, it is said that GET method has vulnerabilities when passing around Json array data:
http://haacked.com/archive/2009/06/25/json-hijacking.aspx
http://haacked.com/archive/2008/11/20/anatomy-of-a-subtle-json-vulnerability.aspx
How do you JQuery experts out there go about fixing this issue? Please help.
--- EDIT: ---
#Gren. Awesome. Thank you. Based on your tips, here is what I figured out.
The normal autocomplete returning json array
and a mod one with a json object wrapping the array
Here is the code, assuming we got a global List named txtlst in the controller.cs...
// normal one
public JsonResult AutoCompleteHelper1(string term) {
//if (!Request.IsAjaxRequest()) return null;
var lst = txtlst.Where(s => s.StartsWith(term)).ToList();
var res = lst.Select(x => new { value = x }).ToList();
return Json(res, JsonRequestBehavior.AllowGet);
}
//mod one
public JsonResult AutoCompleteHelper2(string term) {
//if (!Request.IsAjaxRequest()) return null;
var lst = txtlst.Where(s => s.StartsWith(term)).ToList();
var res = lst.Select(x => new { value = x }).ToList();
return Json(new { wrapper= res, name="wrapper" }, JsonRequestBehavior.AllowGet);
}
}
and then in the .cshtml file...
<p>Auto Complete Example</p>
<input type="text" name="q" id="MyInput1" data-autocomplete-source="#Url.Action("AutoCompleteHelper1", "Home")"/>
<input type="text" name="q" id="MyInput2" data-autocomplete-source="#Url.Action("AutoCompleteHelper2", "Home")" />
and then in the .js file...
$(document).ready(function () {
// normal autocomplete
$("#MyInput1").autocomplete({ source: $("#MyInput1").attr("data-autocomplete-source") });
// mod autocomplete with a wrap
$("#MyInput2").autocomplete({
source: function (req, add) {
$.getJSON($("#MyInput2").attr("data-autocomplete-source"), req, function (data) {
var suggestions = [];
$.each(data.wrapper, function (i, o) {
suggestions.push(o.value);
});
add(suggestions);
});
}
});
});
--- EDIT 2: ---
Please ignore those comments that are telling me to use POST. They
are not reading the blog links or do not understand the issue.
The other option is to wrap your JSON Arrays within JSON objects. The article and comments in it answered this question.
Edit:
From the article:
The fact that this is a JSON array is important. It turns out that a script that contains a JSON array is a valid JavaScript script and can thus be executed. A script that just contains a JSON object is not a valid JavaScript file.
If you wrap your json array in an object {"myJsonArray":[{"name":"sensitive"},{"name":"data"}]} the HTML script tag would not be able to execute.
Security of an Ajax/JSONP/JSON call is the same exact thing as the security of an http call since Ajax requests are http requests. Nothing changes in how you handle it. You make sure the user is logged in and can access the information.
If you are worried about data being cached, use Post or set the proper no caching headers with the backend.
EDIT:
Things you can do to prevent JOSN from being read is the infinite loop trick. Stick an infinte loop in front of the call, means your Ajax call will have to strip this before using it.
You can use keys, third party site would not have the keys needed to validate the request.
You can check referrers.

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