This question already has answers here:
Why does my JavaScript code receive a "No 'Access-Control-Allow-Origin' header is present on the requested resource" error, while Postman does not?
(13 answers)
No 'Access-Control-Allow-Origin' header is present on the requested resource—when trying to get data from a REST API
(26 answers)
Closed 14 days ago.
I am trying to access a JSON from the NYT from this URL: https://www.nytimes.com/svc/wordle/v2/2023-01-30.json
This is my first time using fetch, but whenever I run the following code...
fetch('https://www.nytimes.com/svc/wordle/v2/2023-01-30.json')
.then(response => response.json())
.then(data => {
console.log(data)
});
I get: "TypeError: Failed to Fetch". I am using Replit to run this code, but using this URL (https://deckofcardsapi.com/api/deck/new/shuffle/?deck_count=1) from someone else's example runs perfectly fine in the same piece of code.
I've tried adding await in case the function was taking too long, as well as other forms of HTTP requests. They work when using the deckofcards URL, but not the NYT one.
Is there a specific parameter I need to add for this particular URL? I appreciate any pointers!
Related
This question already has an answer here:
Fetching API json data alert: Content Security Policy: The page’s settings blocked the loading of a resource at
(1 answer)
Closed 4 months ago.
I know there have been lots of questions on this topic and I read them all but not able to resolve my issue so asking here.
I am getting the following error while trying to access an api using fetch-
Refused to connect to 'https://xxxxx/api' because it violates the
following Content Security Policy directive: "connect-src 'self'
updates.developer.mozilla.org
www.google-analytics.com stats.g.doubleclick.net"
I don't have any control over this api so I can't add anything to connect-src. When making a fetch(api_url) request I am getting the above error but while making the same GET request from POSTMAN(or directly from url bar of browser) then I am able to receive the response body(which is an xml).
Also while making a fetch request with mode set to 'no-cors' I am able to get a response but not the response body. I want the response body.
What is POSTMAN doing differently? How can I achieve the same using fetch()?
Try installing the 'CORS Unblock' chrome extension and then run your application. Also, this error generally occurs when we use an API link as http://'apilink' when the link is https://'apilink' or vice-versa. Please check that as well.
This question already has answers here:
How to enable CORS in flask
(11 answers)
Closed 6 months ago.
I am trying to retrieve data(string) from a flask server with the a GET request and the
xhttp.responseText is always an empty string.
Here is my python code
Here is my Html code
edit:
console tab says: Access to XMLHttpRequest at 'http://127.0.0.1:5000/' from origin 'null' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
Instead of triggering the GET from your front-end, can you build the same GET request in Postman and check if it still returns an empty string? (i.e. as a way to debug the issue)
See: Building requests
This question already has answers here:
Why doesn't adding CORS headers to an OPTIONS route allow browsers to access my API?
(36 answers)
How does the 'Access-Control-Allow-Origin' header work?
(19 answers)
No 'Access-Control-Allow-Origin' header is present on the requested resource—when trying to get data from a REST API
(26 answers)
Closed 4 years ago.
im trying to make a simple request to an API
fetch('someurl').then((data) => console.log(data))
but im getting the classic No 'Access-Control-Allow-Origin' header is present on the requested resource.
how can I fix this on the client side? or is the only way to fix it for the API author to change it and add the correct response headers?
To deepen you understand on CORS have a look at MDN's article on Cross-Origin Resource Sharing (CORS). It's pretty extensive.
Using jsonP you would be able to work around this when making simple GET requests. See also this older, short and sweet article that explains it in more detail. How JSONP Works.
The Wikipedia Definition of JSONP is as follows:
a communication technique used in JavaScript programs which run in Web
browsers. It provides a method to request data from a server in a
different domain, something prohibited by typical web browsers because
of the same origin policy.
With that in mind, let look at the following example and make the request.
$(document).ready(function() {
$.getJSON("https://jsonplaceholder.typicode.com/users?callback=?", function(json){
console.log('getJSON call: ', json);
});
})
FETCH does not support jsonp
After a bit of research, it does turn out that the Fetch API does not support jsonP requests. If you have a look at this jsFiddle example you'll see that the $.getJSON call returns data when used with the suffix ?callback=? while the 'fetch()' call fails and returns a CORS message. Open the console to see the result of both calls.
Your question in the comments
Also, do you know why fetch({ url : 'https://randomurl" }) would not
get a CORS blockage but fetch('https://randomurl') would?
The first argument you provide to fetch is a string/URL, the second (optional) argument can be an options object {}. Because you provide an object as the first argument, that URL cannot be found. The reason why it doesn't give you a CORS blockage is because you provided an invalid URL, which returns a 404 status. Fetch deals with page cannot be found errors by returning a 200 OK status and in the JSON returned it will provide you with more info.
The Promise returned from fetch() won’t reject on HTTP error status
even if the response is an HTTP 404 or 500. Instead, it will resolve
normally (with ok status set to false), and it will only reject on
network failure or if anything prevented the request from completing.
Source: MDN docs
I hope this helped a bit in broadening your understanding of CORS and the how Fetch works.
You can find some workaounds in Why does my JavaScript get a "No 'Access-Control-Allow-Origin' header is present on the requested resource" error when Postman does not? but you can't solve the problem from the client. It must be solved on server by setting correct headers that allow it...
This question already has answers here:
How to check if the user is online using javascript or any library?
(11 answers)
Closed 5 years ago.
I have a web page is running on localhost. This web page has some JavaScript that runs when the page is loaded. I want to see if the web page can connect to the external internet.
I thought I would use Axios, to see if I could hit Google. So, I tried the following:
axios.get('https://www.google.com')
.then(function (res) {
alert('Google found!');
})
.catch(function (err) {
console.log(err);
alert('Cannot find Google');
})
;
When this code runs, I see the following error in my console window:
XMLHttpRequest cannot load https://www.google.com/. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:3000' is therefore not allowed access.
My question is, how can I use Axios to see if I can reach the internet?
Axios cannot make cross domain requests, You can try using a cross domain library.
For example, jquery, zepto and so on.
This question already has answers here:
Ways to circumvent the same-origin policy
(8 answers)
Closed 8 years ago.
I'd like to get the text on this page:
https://cvo-v025.cvo-zwfryslan.nl/display/ToonBerichten.aspx?uid=ctl14&pid=723df4e4-248f-4df6-b3ad-751b410daab7&id=1c76d69d-d858-44d9-8a47-e65e9f294898
Php cUrl isn't working, YQL isn't working (but didn't give an error), javascript didn't work, the error message was:
XMLHttpRequest cannot load https://cvo-v025.cvo-zwfryslan.nl/display/ToonBerichten.aspx?uid=ctl14&pid=…3df4e4-248f-4df6-b3ad-751b410daab7&id=1c76d69d-d858-44d9-8a47-e65e9f294898. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://--------.nl' is therefore not allowed access.
Is there a way for me to get the text from that page?
The page you're trying to fetch text from actually makes a POST request to another resource to fetch the text via XHR. When you open Firebug or similar, you should see the POST request, its URL and response. It would appear that you need to have a session on the site to actually fetch anything, as making a POST request to that URL fails to retrieve anything useful.
Copying the request as CURL does yield a working terminal command, along with all sent headers, but I doubt it will be helpful if you wish to do this programmatically.