You won’t be able to make an ajax call to http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml from a file deployed at http://run.jsbin.com due to the same-origin policy. As the source (aka origin) page and the target URL are at different domains (run.jsbin.com and www.ecb.europa.eu), your code is actually attempting to make a Cross-domain (CORS) request, not an ordinary GET. In … Read more
The link you referenced in your question recommends using django-cors-headers, whose documentation says to install the library python -m pip install django-cors-headers and then add it to your installed apps: INSTALLED_APPS = ( … ‘corsheaders’, … ) You will also need to add a middleware class to listen in on responses: MIDDLEWARE = [ …, … Read more
Short answer: Make the request URL in your code isn’t missing a trailing slash. A missing-trailing-slash problem is the most-common cause of the error cited in the question. But that’s not the only cause — just the most common. Read on for more details. When you see this error, it means your code is triggering … Read more
CORS’ preflight request uses HTTP OPTIONS without credentials, see Cross-Origin Resource Sharing: Otherwise, make a preflight request. Fetch the request URL from origin source origin using referrer source as override referrer source with the manual redirect flag and the block cookies flag set, using the method OPTIONS, and with the following additional constraints: Include an … Read more
Cross site approach To allow receiving & sending cookies by a CORS request successfully, do the following. Back-end (server): Set the HTTP header Access-Control-Allow-Credentials value to true. Also, make sure the HTTP headers Access-Control-Allow-Origin and Access-Control-Allow-Headers are set and not with a wildcard *. For more info on setting CORS in express js read the … Read more
You need to remove the mode: ‘no-cors’ setting from your request. Setting no-cors mode is exactly the cause of the problem you’re having. A no-cors request makes the response type opaque. The log snippet in the question shows that. Opaque means your frontend JavaScript code can’t see the response body or headers. https://developer.mozilla.org/en-US/docs/Web/API/Request/mode explains: no-cors … Read more
A good reason is for security – this can prevent CSRF attacks because this header cannot be added to the AJAX request cross domain without the consent of the server via CORS. Only the following headers are allowed across origins: Accept Accept-Language Content-Language Last-Event-ID Content-Type any others cause a “pre-flight” request to be issued in … Read more
XMLHttpRequest cannot load localhost:4201/ticker. Cross origin requests are only supported for protocol schemes: http, data, chrome, chrome-extension, https. Any time you see that “only supported for protocol schemes” message, it almost certainly means you’ve just forgotten to put the https or http on the request URL in your code. So in this case, the fix … Read more
For instances where running a local webserver is not an option, you can allow Chrome access to file:// files via a browser switch. After some digging, I found this discussion, which mentions a browser switch in opening post. Run your Chrome instance with: chrome.exe –allow-file-access-from-files This may be acceptable for development environments, but little else. … Read more