I need to send a value from a input form to a nodejs server, which triggers a calculation with this value and needs to update an p element with the result of the calculation on the client side.
How can this be done?
This is what i have:
//Server side:
app.post('/calculate/:id', function(req, res){
var title = 'Tax Calculation';
var tax= taxcalculation(req.params.id);
res.render('index', {
title: title,
tax: tax,
});
});
//Client side:
var income= document.getElementById("income");
var tax = document.getElementById("tax")
$(income).on('change', function() {
console.log("changed");
$.ajax({
type: 'POST',
url: '/calculate/'+income.value,
success: function() {
$('#tax').html('<%= tax %>');
},
error: function() { // if error occured
alert("Error occured, please try again");
},
});
});
Okay, so you don't give a lot of data, but this sounds as simple as sending a response with the results to the client side in your Node web service that does the calculations and append the result to the P element
Your server code to handle the ajax call should output a json response which will contain the content for the <p>. It should not re-render the whole index page. I don't do a lot of node.js so I'll leave that for you to figure out.
The ajax success function should accept a response as a parameter, and then operate on that response.
Assuming the server response to this ajax request is of the format {"tax": 15.99}:
$.ajax({
type: 'POST',
url: '/calculate/'+income.value,
success: function(response) {
if (response.tax || response.tax === 0) {
$('#tax').html(response.tax);
}
},
error: function() { // if error occured
alert("Error occured, please try again");
},
});
Related
Currently I am using Flask and Jquery and getting a 500 Internal Server Error response in my console. When I post with Ajax to the url on flask, shouldn't it be able to be received? I don't understand why I am getting this error.
Jquery
$('.movie').click(function(){
console.log(this);
$(this).toggleClass('green blue').promise().done(function(){
if ($(this).html() == "Add Movie"){
$(this).html("Added");
}
});
id = $(this).val();
//get information from API
$.ajax({
url: "/profile",
dataType: 'json',
async: true,
data: {id: id},
success: function(data) {
}
});
Python/Flask
#app.route("/profile", methods = ["GET"])
def profile(id):
print("mydata is: ", request.args['id'])
if request.args.get:
print("this API is reached")
id = request.args.get['id']
url_movie = 'https://api.themoviedb.org/3/movie/{}?api_key=78cb6b67a99ce26e6d6619c617d9c907&language=en-US'.format(id)
r = requests.get(url_movie)
code = r.json();
return jsonify(code)
500 is a server error. There is something wrong with the request execution at server side only.
I am using node.js and Express.js on the back end, and am trying to make a server call from the client via AJAX.
So I have this POST request that works fine with AJAX:
node.js/Express.js:
app.post('/createNewThing', function(req, res) {
var userInput = req.body.userInput;
if (userInput) {
res.send('It worked!');
}
});
Client Side/AJAX request:
var userInputForm = $('#userInputForm.val()')
$.ajax({
url: "/createNewThing",
type: "POST",
data: "userInput=" + userInputForm,
dataType: "text",
success: function(response, status, http) {
if (response) {
console.log('AJAX worked!);
}
}
});
The userInputForm comes from an HTML form.
This POST request works fine. But I want to change this to a GET request. If I change app.post to app.get, and change type in the AJAX call to GET, I get this 500 error:
GET /createNewThing?userInput= 500
When you make a GET request, the data appears in the query string (of the URL in the request headers). It doesn't appear in the request body. There is no request body.
When you try to read from the request body, you are trying to access a property of an undefined object, which triggers an exception and cause an internal server error.
This answer explains how to read a query string:
var id = req.query.id; // $_GET["id"]
So
var userInput = req.query.userInput;
I think var userInputForm = $('#userInputForm.val()') will get error or get wrong data..This may be the reason for the error. Due to userInputForm may not be a string and concatenate with userInput=
Actually it is bad data.
And for the data in ajax, you should modify data from data: "userInput=" + userInputForm,
to:
data: {
userInput: userInputForm
},
dataType: "json"
And var userInputForm = $('#userInputForm.val()')
to var userInputForm = $('#userInputForm').val();
At last, you could modify as bellow, I believe it works:
var userInputForm = $('#userInputForm').val();
$.ajax({
url: "/createNewThing?userInput=" + userInputForm,
type: "GET",
success: function(response, status, http) {
if (response) {
console.log('AJAX worked!);
}
}
});
I have a page on a project I'm developing that is attempting to make an ajax request with a specific value assigned by the button's (there are multiple) id tag. This works; the value is successfully passed and an ajax call is triggered on every click.
When I try to make the call again to the same page with a different button the variables are reassigned however the GET request that is sent remains unchanged.
How do I pass a NEW variable (in this case id) passed into the GET request?
function someAJAX(target) {
var trigger = [target.attr('id')];
console.log[trigger];
$.ajax({
// The URL for the request
url: "onyxiaMenus/menuBase.php",
// The data to send (will be converted to a query string)
data: {
//class: target.attr("class"),
tableCall: true,
sort: trigger,
sortOrder: 'DESC',
},
// Whether this is a POST or GET request
type: "GET",
// The type of data we expect back
//The available data types are text, html, xml, json, jsonp, and script.
dataType: "html",
// Code to run if the request succeeds;
// the response is passed to the function
success: function (data) {
console.log("AJAX success!");
$('#prop').replaceWith(data);
}
,
// Code to run if the request fails; the raw request and
// status codes are passed to the function
error: function (xhr, status, errorThrown) {
console.log("Sorry, there was a problem!");
console.log("Error: " + errorThrown);
console.log("Status: " + status);
console.dir(xhr);
}
,
// Code to run regardless of success or failure
complete: function (xhr, status) {
console.log("The request is complete!");
$('#view').prepend(xhr);
}
});
}
$(document).ready(function () {
$(".sort").on( "click", function (e) {
//e.stopPropagation();
//e.preventDefault();
target = $(this);
//console.log(target.attr("class"));
console.log(target.attr("id"));
/* ADD CHILDREN TO ELEMENT*/
if (target.hasClass('asc')) {
target.removeClass('asc')
} else {
target.addClass('asc')
}
/* MANAGE CLASS ADD/REMOVE FOR TARGET AND SIBLINGS */
if (target.hasClass('btn-primary')) {
} else {
target.addClass('btn-primary')
}
someAJAX(target);
target.siblings().removeClass('btn-primary');
})
});
Try to call your ajax like this someAJAX.bind(target)();
Then in function become
function someAJAX() {
$.ajax({
// The URL for the request
url: "onyxiaMenus/menuBase.php",
// The data to send (will be converted to a query string)
data: {
//class: this.attr("class"),
tableCall: true,
sort: this.attr('id'),
sortOrder: 'DESC',
},
// Whether this is a POST or GET request
type: "GET",
// The type of data we expect back
//The available data types are text, html, xml, json, jsonp, and script.
dataType: "html",
// Code to run if the request succeeds;
// the response is passed to the function
success: function (data) {
console.log("AJAX success!");
$('#prop').replaceWith(data);
}
,
// Code to run if the request fails; the raw request and
// status codes are passed to the function
error: function (xhr, status, errorThrown) {
console.log("Sorry, there was a problem!");
console.log("Error: " + errorThrown);
console.log("Status: " + status);
console.dir(xhr);
}
,
// Code to run regardless of success or failure
complete: function (xhr, status) {
console.log("The request is complete!");
$('#view').prepend(xhr);
}
});
}
trigger doesn't seem to be defined anywhere. That's the only data that would be changing between your requests as the other ones are statically coded.
You just need to make sure trigger is defined and changes between the two requests.
Thanks for the input on this problem. I got down to the bottom of my problem. My requests were being handled correctly but dumping the tables was creating syntax errors preventing the appending of new information to my page.
Thanks for the quick replies!
It wall works now.
I'm fairly new to asp.net MVC but am baffled as to why my request isn't working.
I'm trying to send an ajax request with jquery as per:
jQuery(function ($) {
var total = 0,
share = $('div.share'),
googlePlusUrl = "https://plusone.google.com/_/+1/fastbutton?url=http://bookboon.com" + $(location).attr('pathname');
setTimeout(function() {
$.ajax({
type: 'GET',
data: "smelly",
traditional: true,
url: share.data('proxy'),
success: function(junk) {
//var $junk = junk.match(regex);
console.log(junk);
},
error: function (xhr, errorText) {
console.log('Error ' + xhr.responseType);
},
});
}, 4000);
And set a line in my RouteConfig as:
routes.MapRoute(null, "services/{site}/proxy", new { controller = "Recommendations", action = "Proxy" });
The markup has a data-attribute value as:
<div class="share" data-proxy="#Url.Action("Proxy", "Recommendations")">
And my Proxy action method starts with:
public ActionResult Proxy(string junk)
The problem is that the junk parameter is always null. I can see in the debug output that the route seems to correctly redirect to this method when the page loads (as per jQuery's document ready function), but I cannot seem to send any data.
I tried sending simple data ("smelly") but I don't receive that neither.
Any suggestions appreciated!
The model binder will be looking for a parameter in the request called junk, however you're sending only a plain string. Try this:
$.ajax({
type: 'GET',
data: { junk: "smelly" }, // <- note the object here
traditional: true,
url: share.data('proxy'),
success: function(junk) {
//var $junk = junk.match(regex);
console.log(junk);
},
error: function (xhr, errorText) {
console.log('Error ' + xhr.responseType);
},
});
I'm building a RESTful web api with asp.net mvc, which returns pure json data. On my client, I'm using backbone.js to communicate to it.
My question is, how do I capture the message in javascript? For eg. What if a user has no permission to delete or there was no item matching the id? I've been told to throw http errors instead of custom json.
So my code would be:
[HttpDelete]
public ActionResult Index(int id)
{
if (id == 1)
{
throw new HttpException(404, "No user with that ID");
}
else if (id == 2)
{
throw new HttpException(401, "You have no authorization to delete this user");
}
return Json(true);
}
How do I access the message in my javascript callback? The callback would look like:
function (model, response) {
alert("failed");
//response.responseText would contain the html you would see for asp.net
}
I do not see message i threw in the exception anywhere at all in the data that was returned from the server.
You should use the error callback on the client. The success callback is triggered only when the request succeeds:
$.ajax({
url: '/home/index',
type: 'DELETE',
data: { id: 1 },
success: function (result) {
alert('success'); // result will always be true here
},
error: function (jqXHR, textStatus, errorThrown) {
var statusCode = jqXHR.status; // will equal to 404
alert(statusCode);
}
});
Now there is a caveat with 401 status code. When you throw 401 HTTP exception from the server, the forms authentication module intercepts it and automatically renders the LogIn page and replaces the 401 status code with 200. So the error handler will not be executed for this particular status code.
I just answered this in my question What is the point of HttpException in ASP.NET MVC, but you can actually get that string if you use the HttpStatusCodeResult like this:
In your controller:
return new HttpStatusCodeResult(500,"Something bad happened")
And you can access "Something bad happened" using, say, jQuery $.ajax() like this:
$.ajax: {
url: "#Url.Action("RequestsAdminAjax", "Admin")",
type: "POST",
data: function(data) { return JSON.stringify(data); },
contentType: "application/json; charset=utf-8",
error: function (xhr, textStatus,errorThrown) {
debugger;
toggleAlert('<strong>Error: </strong>Unable to load data.', 'alert alert-danger');
}
},
and errorThrown will contain "Something bad happened".
HTH.