I'm making a jQuery AJAX call to my Rails app (all run on localhost) which is responding with Javascript. The javascript is running because I'm getting the alert. But, I would like to read the my_var variable in the js.erb file. However, when I try to look at the data parameter of the success function it sees the data as a string. So doing data.my_var is undefined.
js.erb file
var my_var = "hi";
alert('this ran');
javascript
$.ajax({
url: "/a/validate?a_id=" + "<%= params[:id] %>",
context: this,
dataType: "script",
data:
{
json_a: JSON.stringify(this.a),
model_to_validate: model,
target_class: target_class,
current_class: current_class
},
success: function (data, textStatus, jqXHR) {
if(!this.orderFormViewed) {
this.orderFormViewed = data.order_block_opened;
}
},
error: function (data) {
console.log("error in ajax validate call");
debugger;
}
})
That's because that's exactly what you told it to do with dataType: "script" - look at the dataType options below. The script is run in it's own context and so you won't see that variable (I believe). You're going to need to communicate differently if you want that set. Or if you just need data send json.
https://api.jquery.com/jQuery.ajax/
"script": Evaluates the response as JavaScript and returns it as plain text. Disables caching by appending a query string parameter, "_=[TIMESTAMP]", to the URL unless the cache option is set to true. Note: This will turn POSTs into GETs for remote-domain requests.
try to change your dataType to json if you only need to get an object and be sure your server return a json.
Related
I have a node.js project with frontend written in Pug. On the pug side I have written a Javascript function that is making an Ajax call and returning a string, I am trying to call this function inside that same pug file but it gives me a function not defined error. Can anyone please help with this?
header(class="global-header")
p Current Status: #{getCurrentAvail()}
script.
function getCurrentAvail(){
$.ajax({
url: "/admin/account/accountAvailability",
type: "GET",
contentType: "application/json; charset=utf-8",
async: false,
success: function(data){
console.log("===1")
currentAvail = data.message
console.log(currentAvail)
return data.message
},
error: function(data){
console.log("Error function avail");
}
});
}```
It appears you have some piece of external data and you want that data to show in a rendered web page. You have two basic choices here:
1. Server-side fetching and rendering of the data. You can have your server get the data before rendering the page and pass that data to your template engine so your template engine can insert the data into the page at the appropriate place.
2. Client-side fetching and insertion of the data. You can call the getCurrentAvail() function from within a <script> tag in the web page. This will send the rendered web page to the browser. As it loads, the browser will then execute your script, fetch the data from your server and then you would use DOM APIs in the browser to insert the result of that ajax call into the web page to make it visible to the user in the page.
Also, please note that your function getCurrentAvail() has no return value at all. You aren't returning anything from the outer function. Your return data.message is inside the asynchronous success callback so that just go back to nowhere. If you're going to go with the client-side option #2, then you can just put the DOM manipulation code right into the success callback function.
Your current code is attempting to do 1/2 server and 1/2 client and that is not something that will work.
At all times, have total clarity on what is in the server and what is in the client. Ajax methods run in the browser. A #{variable} construct exists only in Pug, and the substitution occurs on the server.
I think this is what you need:
header(class="global-header")
p Current Status:
span#status
script.
function getCurrentAvail(){
$.ajax({
url: "/admin/account/accountAvailability",
type: "GET",
contentType: "application/json; charset=utf-8",
async: false,
success: function(data) {
document.getElementById("status").innerText = data.message
},
error: function(data){
console.log("Error function avail");
}
});
}
getCurrentAvail();
I have used dojo/dom from a javascript file before to call a php file on another domain that handles some database queries and returns the result to the javascript file.
The call to the php file was (i offcourse hope i can use the same call to asp)
postdata = dojo.toJson({ action: "get", userid: 1 });
require(["dojo/_base/xhr", "dojo/dom", "dojo/domReady!"],
function (xhr, dom) {
var xhrArgs = {
url: "http://otherdomain.com/file.php",
postData: postdata,
handleAs: "text",
load: function (result) { }
};
var deferred = dojo.xhrPost(xhrArgs);
In the php file i had
$foo = file_get_contents("php://input");
$postvalue = json_decode($foo, true);
to read the values from the dom call.
The reason i need to do this is because i get an error from the browser about a security risk because of the cross domain request.
So i think i need to use Jsonp
How do I write the php code in asp? NOT asp.net
Since your post data is JSON, the Request.Form won't be filled in, so you will have to use Request.BinaryRead and convert this result as a string.
See here to convert this JSON string into an object.
I have been having problems with getting AJAX to post JSON correctly. The application is intended to be hosted on Google App Engine. But what I have does not post data.
Python
mainPage = """
<html>
html is included in my python file.
</html>
"""
class JSONInterface(webapp2.RequestHandler):
def post(self):
name =self.request.get('name')
nickname =self.request.get('nickname')
callback = self.request.get('callback')
if len(name) > 0 and len(nickname) >0:
newmsg = Entry(name=name, nickname=nickname)
newmsg.put()
if len(name)>0:
self.response.out.write(getJSONMessages(callback))
else:
self.response.out.write("something didnt work")
def get(self):
callback = self.request.get('callback')
self.response.out.write(getJSONMessages(callback))
This handler is meant to handle the Ajax calls from the web app. I am unsure if I need javascript to be associated with my main page in order to do so, as I haven't found information on it yet with my searches.
Javascript
$(document).ready( function() {
$("#post").bind('click', function(event){
var name = $("#name").val();
var nickname = $("#nickname").val();
postData = {name: name, nickname: nickname, callback: "newMessage"};
$.ajax({
type: "POST",
url: "http://localhost:27080/json",
data: postData,
dataType: "json",
done: function() {
// Clear out the posted message...
$("#nickname").val('');
},
fail: function(e) {
confirm("Error", e.message);
}
});
// prevent default posting of form (since we're making an Ajax call)...
event.preventDefault();
});
The Javascript for the post
Can someone advise me on how I could resolve the problem I am having. Thanks for the time and help.
Did you ask the same question yesterday and then delete it? I swear I just answered the same question.
You're not sending your data as a JSON string. If you want to send as JSON, you need to encode data as a JSON string, or else you're just sending it as a query string.
data: JSON.stringify(postdata),
HOWERVER, your request handler is actually processing the request properly as query string instead of JSON, so you probably don't want to do that.
For starters, the ajax call is pretty close. The full path
"http:://localhost:27080/json"
is not necessary, the relative path will work, but that is not the problem.
Your callback, as it stands, will work as 'success':
success: function(response) {
alert(response);
// Clear out the posted message...
$("#nickname").val('');
}
However, this callback is being phased out in favor of other methods. 'Done' should be chained like so:
$.ajax({
type: "POST",
url: "/json",
data: postData,
dataType: "json"
}).done(function(data){
console.log(data);
});
Also, there might be problems on the server. If you use some logging, you will see that the data is indeed being sent to the server.
import json ## we'll get to this below
import logging
class JSONInterface(webapp2.RequestHandler):
def post(self):
name = self.request.get('name')
logging.info(name) ## will print the value of 'name'
Unless your python function getJSONMessages(callback) is returning a json object, your callback will not be called, even after you add the response parameter.
In your python code:
import json
import logging
class JSONInterface(webapp2.RequestHandler):
def post(self):
callback = self.request.get('callback')
logging.info(callback) # will print correctly
self.response.out.write(json.dumps(callback))
Using the json.dumps method encodes the passing object to json, which is what your ajax object is looking for.
I want to know the content type of a given url input by the user inside my Javascript code. Actually, I have a drop-down list (html,csv,xls etc.) and I want to make it so when the user inputs an url, I want to detect the type of the content of the url and based on this type I want to set the value of my drop-down list (html,csv,xls etc.). I know, I can get the content type using Ruby like this :
require 'open-uri'
str = open('http://example.com')
str.content_type #=> "text/html"
or, also, I could use curl to get the content and then parse it to know the content type. But, I need to do this inside my Javascript code because of my need explained above. Any thought ?
EDIT_1 :
I tried this code in my javascript :
$("#wiki_form_url").change(function(){
$.ajax({
type: "GET",
url: "content.rb",
data: {
// input_url: $("#wiki_form_url").val()
},
dataType: "html"
}).done(function (data) {
// `data` contains the content-type
alert('Success !!!');
}).fail(function () {
alert("failed AJAX call");
});
});
I have a ruby script content.rb inside which I do :
require 'open-uri'
str = open('http://www.ofdp.org/benchmark_indices/25')
str.content_type
But, it does not seem to work. I am getting Ajax failure. May be it's because of url path of the script content.rb ? How should I specify a script path here ? (Relative or absolute)
The same origin policy prevents you from using client side JavaScript to directly discover information about arbitrary URIs (URIs you control are a different story).
You'll need to get that information with another technology, such as your server side Ruby.
You could do this by simply submitting a form to the server and returning a new webpage to the browser.
If you don't want to leave the page, then you can pass the data using Ajax. There are no shortage of Ajax tutorials out there, here is a good one from MDN.
Here's an example of an AJAX call:
$(document).ready(function () {
$("#button_check").on("click", function () {
$.ajax({
type: "GET",
url: "Your URL",
data: {
input_url: $("#textbox_id").val()
},
dataType: "html"
}).done(function (data) {
// `data` contains the content-type
alert(data);
}).fail(function () {
alert("failed AJAX call");
});
});
});
Where your HTML is something like:
<input type="text" id="textbox_id" />
<input type="button" id="button_check" value="Submit" />
And your Ruby code would be something like:
require 'open-uri'
class TestController < ApplicationController
def index
req = open(params[:input_url])
render :text => req.content_type
end
end
I have never used RoR before, so I have no idea if this is right or works in the slightest. But it's what I could quickly conjure up when scrambling through several tutorials. It's simply the concept you seem to be looking for. You'll need to figure out how to map a URL to this method, and then update the AJAX option url to use that.
So in the Javascript code - in the done method, that means the whole AJAX request was successful and the data variable should contain the result from the Ruby code req.content_type.
Atlast I could figure out the whole thing with the great help of #Ian. Here is my completed code : In javascript file :
$("#wiki_form_url").change(function () {
$.ajax({
type: "GET",
url: "/wiki_forms/content",
data: {
input_url: $("#wiki_form_url").val()
},
dataType: "text"
}).done(function (data) {
// `data` contains the content-type
alert('Success');
console.log(data);
// alert(data);
}).fail(function () {
alert("failed AJAX call");
});
});
Inside my wiki_forms controller I created a new method named content :
def content
req = open(params[:input_url])
render :text => req.content_type
end
Then added a new route in routes.rb file :
get "/wiki_forms/content" => 'wiki_forms#content'
and used /wiki_forms/content as the ajax request url. And, everything is working nicely now.
I am using jsonp and ajax to query a web-service written in java on another server. I am using the following jquery command:
$.ajax({
type: "GET",
url: wsUrl,
data: {},
dataType: "jsonp",
complete: sites_return,
crossDomain: true,
jsonpCallback: "sites_return"
});
function jsonp_callback(data) {
console.log(data);
}
function sites_return(data) {
console.log(data);
}
So my problem is that after the query finishes a function called jsonp_callback is called. Where I can clearly see the json formatted string:
{"listEntries":["ELEM1", "ELEM2", "ELEM3", etc...]}
But after the function sites_return is called when the complete event fires, I get the the following:
Object { readyState=4, status=200, statusText="parsererror"}
Also for reference the jsonp_callback function is called before the sites_return function. Also if i take the jsonp_callback function out of the code, I get a complaint it firebug that the function is not implemented.
My question three fold:
1) What am i doing wrong on the jquery side?
2) Why does the json get parsed correctly in jsonp_callback but not sites_return?
3) What can i do to fix these issues?
EDIT
Some new development. Per the comments here is some additional information.
The following is what comes out of the http response
jsonp_callback({"listEntries":["ELEM1", "ELEM2", "ELEM3"]})
I assume this is the reason jsonp_callback is being called. I guess my question now becomes, is there any way to control this (assuming i don't have access to the back end web-service).
Hope this helps~
var url = "http://maps.google.com/maps/api/geocode/json?address=1600+Amphitheatre+Parkway,+Mountain+View,+CA&sensor=false";
var address = "1600+Amphitheatre+Parkway";
var apiKey = "+Mountain+View,+CA";
$.getJSON("http://maps.google.com/maps/geo?q="+ address+"&key="+apiKey+"&sensor=false&output=json&callback=?",
function(data, textStatus){
console.log(data);
});
I believe that the first argument to the sites_return function would be the jqXHR Object. Instead of complete try using success.
But still this may not work as it seems that there is a parsing error (mentioned in the return value of sites_return function called from oncomplete). Therefore, you would first need to check your json string.
To Validate JSON, you can use http://jsonlint.com/
I think that the problem is that your server is not behaving the way jQuery expects it to. The JSONP "protocol" is not very stable, but generally what's supposed to happen is that the site should look for the "callback" parameter and use that as the function name when it builds the JSONP response. It looks as if your server always uses the function name "jsonp_callback".
It might work to tell jQuery that your callback is "jsonp_callback" directly:
$.ajax({
type: "GET",
url: wsUrl,
data: {},
dataType: "jsonp",
complete: sites_return,
crossDomain: true,
jsonpCallback: "jsonp_callback"
});
Not 100% sure however.
If you don't have the ability to change the JSONP function wrapper that the remote server returns, jQuery's $.ajax() may be overkill here. Ultimately, all you're doing is injecting a script reference to wsUrl, which makes a call to jsonp_callback with a JavaScript object literal as its input parameter.
You could just as easily do something like this and avoid the confusion around the callback naming/syntax:
$.getScript(wsUrl);
function jsonp_callback(response) {
// Access the array here via response.listEntries
}