My app is an Ember.js front end with a Go API on the server. I created the Ember app using the FixtureAdapter. Now that I have the Go API back end I converted it to RESTAdapter.
When I hit my API directly with the browser, I seem to get the appropriate CORS headers back:
Access-Control-Allow-Credentials:true
Access-Control-Allow-Headers:Origin,x-requested-with
Access-Control-Allow-Methods:PUT,PATCH,GET,POST
Access-Control-Allow-Origin:*
Access-Control-Expose-Headers:Content-Length
However, when my Ember.js app hits the API, I get XMLHttpRequest cannot load https://192.168.59.103:8001/notifications. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://192.168.59.103:9000' is therefore not allowed access..
I don't know how else to see what's going on between Ember and the API. I've read this CORS tutorial and everything seems to be okay on the server end.
I included the bit about x-requested-with because of another Stack Overflow question suggesting that jQuery requests need something different than plain old JavaScript requests.
Your endpoints also need to respond with CORS headers to OPTIONS requests- those will execute before the actual request to make sure that the request is allowed first.
Do you happen to be using Nginx as your reverse proxy for your API? If so, we experienced this same issue. In our case, the problem was that Nginx returns the correct CORS headers just fine for HTTP 200 OK responses, but for any error response, it will fail to add the COR headers and therefore the actual server response gets obscured by the browser complaining that it doesn't have the appropriate CORS headers to render a response.
See https://serverfault.com/a/431580/199943.
Even if you're not using Nginx, try calling your API directly (e.g. using Postman to avoid the CORS restrictions to see what it's returning. If your API is returning anything other than an HTTP 200 OK, that may be why the CORS headers aren't getting added.
Related
I have a django backend and a Vue 3 frontend.
For handling some request, my backend needs an 'Id-Client' header in the headers of the request.
Developing my BE everything worked like a charm, but now that I'm writing the FE I'm encountering some issues.
As I said before, I need to append an header to my headers in every request.
So the first step was the following:
// Note that the idClient is dynamic and can change.
this.$axios.setHeader('Id-Client', idClient)
const data = await this.$axios.$get(url)
But I can't get it to work, if I try to send that request, my GET request becomes (I don't know why) a OPTIONS request and I get the error "cross origin resource sharing error: HeaderDisallowedByPreflightResponse"
Instead if I remove the set header
// this.$axios.setHeader('Id-Client', idClient)
const data = await this.$axios.$get(url)
The server just respond me correctly giving me the error that the request is missing the 'Id-Client' in the header.
I also have a few request that don't need the 'Id-client' header and those request work, so I don't think is a CORS problem.
Well but is looks like CORS issue. CORS policies are not triggered by simple requests. By adding custom header, your requests are no longer simple and trigger CORS policies (sending OPTIONS before GET)
Your only option is to configure your backend server to reply to OPTIONS requests with the correct headers - Access-Control-Allow-Origin and Access-Control-Allow-Headers (server telling the browser "yes, im ok to accept particular custom header")
IF (and only if) you are planning to serve your Vue SPA from the same API server in production (same origin), you can avoid similar CORS issues during development by using Webpack Dev server Proxy - your SPA will send API requests to Webpack Dev Server (used for developing SPA) and Proxy will route it to your Django dev server. That way all request from your SPA are to the same origin and you don't need to care about CORS at all...
I was trying to use my api and I have a function on ember app to login but when the login action is trigerred I receive a message below. What is the reason I am receiving this error?
login:1 Access to fetch at 'https://app-dev.some-url.com.au/api/login' from origin
'http://localhost:4099' has been blocked by CORS policy: Response to preflight request doesn't
pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested
resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch
the resource with CORS disabled.
Your API server isn’t configured to accept requests that come from a web application on another origin. Some options:
Configure your API to serve the Access-Control-Allow-Origin header
on the OPTIONS request that the browser makes to test this. It
could be Access-Control-Allow-Origin: * if you’re lazy or can’t
know in advance what origins people will be coming from. It’s hard
to be more specific about this without knowing details of your API.
Use Ember CLI’s API
proxying
feature to bypass the need for CORS. This is for development mode
only, though. You’d need a similar solution in production where
Ember CLI’s development server isn’t present.
I've created an API with C++ and the following library: https://github.com/yhirose/cpp-httplib
In the API I've added a header to responses for CORS:
svr.Post("/suggest", [&dr](const Request &req, Response &res){
res.set_header("Access-Control-Allow-Origin","(origin here)");
(origin here) is the origin of the server making the request.
On the browser side I've also enabled an extension to bypass CORS. But when trying to make an AJAX request to the API, I still get this error in my browser console:
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://192.168.1.10:10120/suggest. (Reason: CORS request did not succeed).
The AJAX request is done through a script written in the Tampermonkey extension to work on a specific website.
Do I need to modify headers on the server hosting the website? Have I done something wrong on the C++ side?
Also it might be important to mention that the code worked before. All I did was come back to it another day with a different local IP address (which i reprogrammed into the c++ API)
I tried it again to answer #sideshowbarker and it gave me a new error about self signed certificates. After adding the exception it worked.
I need to call a REST-ful webservice in using a GET method with some parameters and save the output of the same.
My first approach was to make some requests in JavaScript and log the output using console.log(), but the server doesn't allow CORS. So I can't make it that way.
I am pretty sure this might be a common thing but I can't seem to find a simple way to do it. What would be the simplest way to do it? Is there any software that would allow me to make an array, let's say with 100 parameters, save 100 calls or what would be a better way to do it? PHP script?
p.s. I can't activate CORS in the server, nor can I place code in the same domain. So far I have an example I can call in the browser and have the XML return.
As far as CORS is concerned, that has to do with the API you're running on not allowing requests to be made from a different domain. This could be fixed by allowing CORS in the API you are developing on.
CORS Link: https://developer.mozilla.org/en-US/docs/Web/HTTP/Access_control_CORS
The other option would be to have your website on the same domain as the API.
Once you have done that, you can simply make multiple AJAX requests to the API.
AJAX HTTP GET example: HTTP GET request in JavaScript?
EDIT:
You might also have to enable CORS in the HTTP header of your request. This would have to be added to an AJAX request:
Access-Control-Request-Headers: x-requested-with
Here is a helpful link for jquery in particular: How to get a cross-origin resource sharing (CORS) post request working
I'm using the Postman packaged app + the interceptor extension. It seems that chrome adds an Origin: chrome-extension://aicmkgpgakddgnaphhhpliifpcfhicfo header automatically for requests that come from Postman. I want to remove this header completely.
When using the Interceptor extension, if I use the regular Postman headers tab to enter an entry for the Origin header, then my request uses the specified value. So, I can change the value of the header. I then tried leaving the value field blank for the header, but then my request reverts to sending Origin: chrome-extension://....
How do I send a request with postman that either sends a blank Origin header, or totally omits it?
I tried it by myself and hope my solution will suit you.
When I make a POST request using Chrome app it adds origin header.
But when I use the desktop app no header is added to my POST request.
Here is an example of header sent by the desktop Postman app:
I am unable to use Postman desktop app (corporate policy yey!) so I'm stuck with Chrome extension Postman.
I was able to overwrite the Origin header by installing Postman Interceptor extension. You also need to active the Interceptor app in Chrome AND Postman.
More detailed instructions can be found here: https://stackoverflow.com/a/41564921/1169726