JAX-RS JSON object to JavaScript - javascript

I am new to JAX-RS and trying to build a simple website interface.
So I have written a function returning a JSON object
like this:
#GET
#Path("/mypath")
#Produces (Mediatype.APPLICATION_JSON)
public String returnJson() {
String json = //.... fill String
return json;
}
which works well when browsing to this path.
On the other hand I have a UI page like this:
#GET
Produces(MediaType.TEXT_HTML)
public InputStream viewUI() throws FileNotFoundException {
File page = new File("page.html");
return new FileInputStream(page);
}
which works also.
Next thing I want to do is filling a dropdown list in my page.html with JavaScript, which also should not be a problem.
But I dont know how to get the JSON object to the JavaScript array (in page.html).

First of all, when using jaxrs, you don't need to convert objects to json. This is done automatically by jaxrs. Your method should return an object. As you asking to convert json into array, I assume, your method should return a List. Regarding of how to call and consume results from the rest service, as per Luts Horn comment, you need to use some sort of client side library, for example jquery.
You can look here http://www.tutorialspoint.com/jquery/jquery-ajax.htm

Related

Loading model in tensorflowjs from string

I have a json string representing a model stored in a js variable. I created it using a gui that generates this json. I would like to load it to tensorflow using tf.loadModel, but the API only accepts url or localstorage. Is there any way to do it directly from string?
Unfortunately Tensorflow.js doesn't provide any way to do this currently.
However, if you need to do it with a string, a possible workaround is to save the string directly to localStorage and retrieve it from there with the URI.
Something like this (untested):
var modelJson = { ... }
localStorage.setItem('model', JSON.stringify(modelJson))
const model = await tf.loadModel('localstorage://model');

Rendering View with Data from Zend Controller for Angular JS

I am in need of this unique requirement where my backend is PHP with Zend Framework in MVC pattern and frontend is Angular JS, I need to pass data from the backend to the Angular JS controller and render the view at the same time.
As far as I know if the backend class inherits Zend_Controller_Action, it returns only View and not data and if the backend class inherits Zend_Rest_Controller, it returns only data and not view.
Is this right and is there a way to render the view as well as return the data without using the $this->view->data concept.
For returning JSON data all you need is the JSON Action Helper
public function someAction() {
// create an array with your data
$data = array();
// to add some view data
$data['html'] = $this->view->render('/path/to/script/script-name.phtml');
// essentially you can load and render any script and I am
// not 100% sure but without a path it would render the default
// action script in view/scripts/controller-name/action-name.phtml
// Send the JSON response. Both methods do the same
$this->_helper->json($data);
$this->_helper->json->sendJson($data);
// NOTE both methods terminate and return the data
// i.e. the follow should not been seen
echo "This should not be seen!";
}
This helper will set the appropriate headers and simply return a JSON object. If you have some error handling in your action and need to return codes other than 200OK you can also fetch the response object $this->getResponse() and set those values.
There are other variations where you would set layout to noRender and contexts but that's all handled already by the JSON helper.

Read JSON String Shown In URL Using Javascript

i am trying to create a simple web app that gets the latitude and longitude stored in a JSON string and uses them to place markers on a google map. Currently, I have a program on a server which retrieves a JSON string with data when a URL is entered into a web browser. The JSON string produced is as follows:-
{"employees":[{"email":"bones93#hotmail.co.uk","lat":"53","lon":"-3","alt":"0","date":"unknown","time":"unknown"},{"email":"unknown","lat":"0","lon":"0","alt":"0","date":"unknown","time":"unknown"},{"email":"unknown","lat":"0","lon":"0","alt":"0","date":"unknown","time":"unknown"}]}
What method could i use in JavaScript that would allow me to get the JSON string that is produced?
P.S I know I will need to parse the text afterwards to make a JSON Object, this is something that can be done afterwards.
Use the Jquery library's get method to request the data from the server. Here is a link to a simple W3 tutorial : http://www.w3schools.com/jquery/ajax_get.asp
Your code will look something like this:
$("button").click(function(){
$.get("/your/server/url",function(data){
var result = JSON.parse(data);
// Process result.employees
});
});
You could use
var x = JSON.parse('{"employees":[{"email":"bones93#hotmail.co.uk","lat":"53","lon":"-3","alt":"0","date":"unknown","time":"unknown"},{"email":"unknown","lat":"0","lon":"0","alt":"0","date":"unknown","time":"unknown"},{"email":"unknown","lat":"0","lon":"0","alt":"0","date":"unknown","time":"unknown"}]}');
and then access it with:
x["employees"][0]["lat"];
try this for normal strings:
JSON.parse(str)
or if you're using AJAX to get that Json you can use as following:
$.get(..,'json')
OR
$.post(..,'json')

Passing Code as String

I have created a Web API that will receive Input from Jquery and will use this input to dynamically alter a string that's stored in a resource file.
This String happens to be an almost complete piece of vbscript code that I plan on passing back down to my website.
My problem is that the resource automatically "stringifies" the Code and the output is flooded with escape characters which renders it completly unusable as actual code.
Is there a way to store the code in a way that makes escape strings unneccesary while still enabling me to alter it similiar to "if it were a string" and pass it down to my Website?
The goal is to then use Jquery/Javascript to make this code into an actual vbscript file and let the user download it.
As per request here some Code.
public string GetDeployment(Deployment deployment)
{
string vbs = Resource1.vbs;
vbs = vbs.Replace("%environment%", deployment.SystemKind);
vbs = vbs.Replace("%platform%", deployment.PlatformKind);
vbs = vbs.Replace("%application%", deployment.ApplicationName);
vbs = vbs.Replace("%config", deployment.ConfigInfix ?? "Null");
vbs = vbs.Replace("%subFolder%", deployment.subFolder ?? "Null");
return vbs;
}
This method alters the vbscript depending on the Input. The API itself receives a JSON with Data for all the properties of deployment.
public class DeploymentController : ApiController
{
private DeploymentRepository DeploymentRepository;
public DeploymentController()
{
DeploymentRepository = new DeploymentRepository();
}
[HttpPost]
public string Post([FromBody]Deployment deployment)
{
return DeploymentRepository.GetDeployment(deployment);
}
}

How to use MS Ajax PageMethods to call a function on the server

I have a project that uses PageMethods to call functions on the server.
The server functions (written in C#) return the values as array of strings, without doing any kind of serialization and in the client side (from Js) the accessing of the return values is by using static variable called arguments.
I found that sometimes for some users (cases are not repro) sometimes an exception occured
"WebServiceFailedException the server method 'Foo' returned invalid data.
the 'd' property is missing from JSON."
Some searching on google I found that people are serializing the return values using DataContractJsonSerializer class and in js accessing the return value using one of the callback function
Example:
function OnRequestComplete(result,
userContext, methodName) {
var Person = eval('(' + result + ')');
alert(Person.Forename);
alert(Person.Surname); }
So is the first technique is correct? or what?
P.S:
the function on the server is defined on the default.aspx.cs file as follows:
[System.Web.Services.WebMethodAttribute(), System.Web.Script.Services.ScriptMethodAttribute()]
public static string[] Foo(string s);
from the client side the calling is as follows
PageMethods.Foo("value",OnSuccess);
Also all the users have the same browser version (IE8)
I don't know if it's the entire problem, but your first issue is manually serializing the return value. PageMethods and ScriptServices automatically JSON serialize their return values. Nesting two levels of JSON could definitely be throwing a wrench in the framework's client-side deserialization process (which is also happening automatically, before your eval() code).
To return an instance of your Person class, this is all you need:
public static Person GetPerson() {
Person p = new Person();
// Populate the Person object here.
return p;
}
Then, on the client-side you can work with the object's properties as expected:
function OnRequestComplete(result, userContext, methodName) {
console.log('Person name: ' + result.Forename + ' ' + result.Surname);
}
Alternatively, if you're using jQuery for other tasks and already have it on the page, you don't even need the ScriptManager and MS AJAX to call page methods. You can directly call page methods with jQuery and skip all that overhead.
Without knowing how the request is made and how the server end is coded, my answer may not be accurate.
Where is the WebMethod decorated method in your server side code? If it is an a separate class with the ScriptService attribute, and if JSON is specified while making the request, then the JSON values should have been automatically serialized and dont need to be serialized manually again. With this set up ASP.NET 3.5 wraps the response in a "d" object
Some users getting the exception might be due to the browser that they are using. If you are using jQuery, I'd specify the content type as so in the ajax request body
contentType: "application/json; charset=utf-8",
Hakeem
This is a bit funky. ASP.NET always adds the "d" to all results. So it either should work or not. Here is some background on the "d" issue:
http://encosia.com/2009/06/29/never-worry-about-asp-net-ajaxs-d-again/

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