How to get JSON from URL in JavaScript? - Stack Overflow

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This URL returns JSON:

{
  query: {
    count: 1,
    created: "2015-12-09T17:12:09Z",
    lang: "en-US",
    diagnostics: {},
    ...
  }
}

I tried this, and it didn't work:

responseObj = readJsonFromUrl('...');
var count = responseObj.query.count;

console.log(count) // should be 1

How can I get a JavaScript object from this URL's JSON response?

This URL returns JSON:

{
  query: {
    count: 1,
    created: "2015-12-09T17:12:09Z",
    lang: "en-US",
    diagnostics: {},
    ...
  }
}

I tried this, and it didn't work:

responseObj = readJsonFromUrl('http://query.yahooapis.com/v1/publ...');
var count = responseObj.query.count;

console.log(count) // should be 1

How can I get a JavaScript object from this URL's JSON response?

• javascript
• json

Share Improve this question Follow edited Apr 21, 2019 at 16:30 Kamil Kiełczewski 92.2k3434 gold badges394394 silver badges370370 bronze badges asked Sep 17, 2012 at 13:34 Yiğit Doğuş ÖzçelikYiğit Doğuş Özçelik 2,82322 gold badges1717 silver badges2020 bronze badges 2

• 1 What you have is a URL that returns a response containing a JSON string. Are you asking how to request something from a URL? Because that would depend a lot on the language or tool that you're using. Be more specific. – jonvuri Commented Sep 17, 2012 at 13:37
• 1 This question is confusing. Don't you get the JSON object by using the URL you mentioned? What do you mean by getting the JSON object from a URL? please clarify. – Steven Commented Sep 17, 2012 at 13:37

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12 Answers 12

Sorted by: Reset to default 232

You can use jQuery .getJSON() function:

$.getJSON('http://query.yahooapis.com/v1/public/yql?q=select%20%2a%20from%20yahoo.finance.quotes%20WHERE%20symbol%3D%27WRC%27&format=json&diagnostics=true&env=store://datatables.org/alltableswithkeys&callback', function(data) {
    // JSON result in `data` variable
});

If you don't want to use jQuery you should look at this answer for pure JS solution.

If you want to do it in plain javascript, you can define a function like this:

var getJSON = function(url, callback) {
    var xhr = new XMLHttpRequest();
    xhr.open('GET', url, true);
    xhr.responseType = 'json';
    xhr.onload = function() {
      var status = xhr.status;
      if (status === 200) {
        callback(null, xhr.response);
      } else {
        callback(status, xhr.response);
      }
    };
    xhr.send();
};

And use it like this:

getJSON('http://query.yahooapis.com/v1/public/yql?q=select%20%2a%20from%20yahoo.finance.quotes%20WHERE%20symbol%3D%27WRC%27&format=json&diagnostics=true&env=store://datatables.org/alltableswithkeys&callback',
function(err, data) {
  if (err !== null) {
    alert('Something went wrong: ' + err);
  } else {
    alert('Your query count: ' + data.query.count);
  }
});

Note that data is an object, so you can access its attributes without having to parse it.

With Chrome, Firefox, Safari, Edge, and Webview you can natively use the fetch API which makes this a lot easier, and much more terse.

If you need support for IE or older browsers, you can also use the fetch polyfill.

let url = 'https://example.com';

fetch(url)
.then(res => res.json())
.then(out =>
  console.log('Checkout this JSON! ', out))
.catch(err => console.log(err));

MDN: Fetch API

Even though Node.js does not have this method built-in, you can use node-fetch which allows for the exact same implementation.

ES8(2017) try

obj = await (await fetch(url)).json();

async function load() {
    let url = 'https://my-json-server.typicode.com/typicode/demo/db';
    let obj = await (await fetch(url)).json();
    console.log(obj);
}

load();

you can handle errors by try-catch

async function load() {
    let url = 'http://query.yahooapis.com/v1/publ...';
    let obj = null;
    
    try {
        obj = await (await fetch(url)).json();
    } catch(e) {
        console.log('error');
    }
    
    console.log(obj);
}

load();

Define a function like:

fetchRestaurants(callback) {
    fetch(`http://www.restaurants.com`)
       .then(response => response.json())
       .then(json => callback(null, json.restaurants))
       .catch(error => callback(error, null))
}

Then use it like this:

fetchRestaurants((error, restaurants) => {
    if (error) 
        console.log(error)
    else 
        console.log(restaurants[0])

});

Axios is a promise based HTTP client for the browser and node.js.

It offers automatic transforms for JSON data and it's the official recommendation from the Vue.js team when migrating from the 1.0 version which included a REST client by default.

Performing a GET request

// Make a request for a user with a given ID
axios.get('http://query.yahooapis.com/v1/publ...')
  .then(function (response) {
    console.log(response);
  })
  .catch(function (error) {
    console.log(error);
  });

Or even just axios(url) is enough as a GET request is the default.

async function fetchDataAsync(url) {
    const response = await fetch(url);
    console.log(await response.json());
}

fetchDataAsync('paste URL');

            async function Fetching()
            {
                const response = await fetch('https://business-api-account.github.io/API.json');
                const jsonData = await response.json();
                console.log(jsonData);
            }

            Fetching();

When fetching a file it is required to use an awaited asynchronous method call. The file content must be extracted asynchronously and awaited because the fetch() method is returning the response in with a promise, meaning that the response is promised, not guaranteed. By awaiting the call, the program will wait in the point where the method call is performed until the promise is returned, and not continue the execution if the promise was not received yet, with the file content or not.

as @DanAlboteanu answer in this page and some error corection of that javascript my suggested code is:

fetchRestaurants((error, data) => {
    if (error)
        console.log(error); 
    else
        console.log(data)

});

and fetchRestaurants method is(please replace your json url with {your url of json data}):

function fetchRestaurants(callback) {
    fetch("{your url of json data}")
       .then(response => response.json())
       .then(json => callback(null, json))
       .catch(error => callback(error, null))
}

//Resolved
const fetchPromise1 = fetch(url);
    fetchPromise1.then(response => {
      console.log(response);
    });


//Pending
const fetchPromise = fetch(url);
console.log(fetchPromise);

this morning, i also had the same doubt and now its cleared i had just used JSON with 'open-weather-map'(https://openweathermap.org/) api and got data from the URL in the index.html file, the code looks like this:-

 //got location
 var x = document.getElementById("demo");
      if (navigator.geolocation) {
        navigator.geolocation.getCurrentPosition(weatherdata);
      } else { 
        x.innerHTML = "Geolocation is not supported by this browser.";
      }
    //fetch openweather map url with api key
    function weatherdata(position) {
//put corrdinates to get weather data of that location
      fetch('https://api.openweathermap.org/data/2.5/weather?lat='+position.coords.latitude+'&lon='+position.coords.longitude+'&appid=b2c336bb5abf01acc0bbb8947211fbc6')
      .then(response => response.json())
      .then(data => {
      console.log(data);
      document.getElementById("demo").innerHTML = 
      '<br>wind speed:-'+data.wind.speed + 
      '<br>humidity :-'+data.main.humidity + 
      '<br>temprature :-'+data.main.temp  
      });
    }

  <div id="demo"></div>

i had give api key openly because i had free subscription, just have a free subscriptions in beginning. you can find some good free api's and keys at "rapidapi.com"

You can access JSON data by using fetch() in JavaScript

Update url parameter of fetch() with your url.

fetch(url)
    .then(function(response){
        return response.json();
    })
    .then(function(data){
        console.log(data);
    })

Hope It helps, it worked perfectly for me.

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