I have a user authentication server setup using Express and Node.js in my localhost Port 3333 and I am trying to connect to the endpoint in Next.js port 3000 using isomorphic-unfetch for the fetch. I am getting a CORS 401 error, I have done a fair bit of research already but just wanted to know whether it was possible connecting to a Express server on localhosts? I have tried adding "Access-Control-Allow-Origin": "*", "Content-Type": "multipart/form-data" to a header object. The express server has cors setup already.
This function below is called on click of a button.
onLoginClick = async () => {
let header = new Headers({
"Access-Control-Allow-Origin": "*",
"Content-Type": "multipart/form-data"
});
const res = await fetch("http://localhost:3333", {
method: "POST",
header,
body: JSON.stringify({
username: "USER",
password: "PASSWORD"
})
});
}
Error message -
http://localhost:3333/ 401 (Unauthorized)
Response {type: "cors", url: "http://localhost:3333/", redirected: false, status: 401, ok: false, …}
First of all, CORS is configured on the server side. You configure your server to allow calls from specific origins.
In your code, onLoginClick is a client-side code, it runs on the browser, client cannot decide which origin the server should allowed to, that would defeat the purpose of having CORS.
Usually you don't need to change the cors configuration in a Next.js app, because you would be calling the API from the same origin that hosted the client side app.
By default, Next.js only support same-origin for API Routes, if you need to customize it, you can use micro-cors.
Im trying to get api-data in angularjs using django application. when i try to access api i get error- Credential is not supported if the CORS header ‘Access-Control-Allow-Origin’ is ‘*’ and CORS request did not succeed . API is hosted in seperate django app.
INSTALLED_APPS = [
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'Bigflow.Core',
'rest_framework',
'Bigflow.API',
'rest_framework.authtoken',
'corsheaders'
]
MIDDLEWARE = [
'corsheaders.middleware.CorsMiddleware',
'django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware',
]
CORS_ORIGIN_ALLOW_ALL = True # i teried false using CORS_ORIGIN_WHITELIST = (
'localhost:8001',
)
CORS_ALLOW_CREDENTIALS = True # i tried both false and true
my js
this.api = function () {
var response = $http.get("http://127.0.0.1:8000/Schedule_Master?Entity_gid=1&Action=FOLLOWUP_REASON&Schedule_Type_gid=1",{headers: {
'Authorization': 'Token 7111*******************',
'Accept': 'application/json',
'Access-Control-Allow-Origin':'*'
}})
return response;
}
I had tried many solution from stackoverflow. I cant able to solve my problem ,OR do I want to change any config in my api hosted server(Django app). Please guide me. Thanks in advance
This error should be about the Access-Control-Allow-Origin setting.
The CORS_ORIGIN_ALLOW_ALL = True will surely cause the problem.(Check the following link)
So except localhost:8001, try to whitelist http://127.0.0.1:8001as well, which may solve this problem. The browser treats localhost and 127.0.0.1 as different domains.
Reason: Credential is not supported if the CORS header ‘Access-Control-Allow-Origin’ is ‘*’
The CORS request was attempted with the credentials flag set, but the server is configured using the wildcard ("*") as the value of Access-Control-Allow-Origin, which doesn't allow the use of credentials.
To correct this problem on the client side, simply ensure that the credentials flag's value is false when issuing your CORS request.
If the request is being issued using XMLHttpRequest, make sure you're not setting withCredentials to true.
If using Server-sent events, make sure EventSource.withCredentials is false (it's the default value).
If using the Fetch API, make sure Request.credentials is "omit".
If, instead, you need to adjust the server's behavior, you'll need to change the value of Access-Control-Allow-Origin to grant access to the origin from which the client is loaded.
How to share cookies cross origin? More specifically, how to use the Set-Cookie header in combination with the header Access-Control-Allow-Origin?
Here's an explanation of my situation:
I am attempting to set a cookie for an API that is running on localhost:4000 in a web app that is hosted on localhost:3000.
It seems I'm receiving the right response headers in the browser, but unfortunately they have no effect. These are the response headers:
HTTP/1.1 200 OK
Access-Control-Allow-Origin: http://localhost:3000
Vary: Origin, Accept-Encoding
Set-Cookie: token=0d522ba17e130d6d19eb9c25b7ac58387b798639f81ffe75bd449afbc3cc715d6b038e426adeac3316f0511dc7fae3f7; Max-Age=86400; Domain=localhost:4000; Path=/; Expires=Tue, 19 Sep 2017 21:11:36 GMT; HttpOnly
Content-Type: application/json; charset=utf-8
Content-Length: 180
ETag: W/"b4-VNrmF4xNeHGeLrGehNZTQNwAaUQ"
Date: Mon, 18 Sep 2017 21:11:36 GMT
Connection: keep-alive
Furthermore, I can see the cookie under Response Cookies when I inspect the traffic using the Network tab of Chrome's developer tools. Yet, I can't see a cookie being set in in the Application tab under Storage/Cookies. I don't see any CORS errors, so I assume I'm missing something else.
Any suggestions?
Update I:
I'm using the request module in a React-Redux app to issue a request to a /signin endpoint on the server. For the server I use express.
Express server:
res.cookie('token', 'xxx-xxx-xxx', { maxAge: 86400000, httpOnly: true, domain: 'localhost:3000' })
Request in browser:
request.post({ uri: '/signin', json: { userName: 'userOne', password: '123456'}}, (err, response, body) => {
// doing stuff
})
Update II:
I am setting request and response headers now like crazy now, making sure that they are present in both the request and the response. Below is a screenshot. Notice the headers Access-Control-Allow-Credentials, Access-Control-Allow-Headers, Access-Control-Allow-Methods and Access-Control-Allow-Origin. Looking at the issue I found at Axios's github, I'm under the impression that all required headers are now set. Yet, there's still no luck...
Cross site approach
To allow receiving & sending cookies by a CORS request successfully, do the following.
Back-end (server) HTTP header settings:
Set the HTTP header Access-Control-Allow-Credentials value to true.
Make sure the HTTP headers Access-Control-Allow-Origin and Access-Control-Allow-Headers are set. Don't use a wildcard *. When you set the allowed origin make sure to use the entire origin including the scheme, i.e. http is not same as https in CORS.
For more info on setting CORS in express js read the docs here.
Cookie settings:
Cookie settings per Chrome and Firefox update in 2021:
SameSite=None
Secure
When doing SameSite=None, setting Secure is a requirement. See docs on SameSite and on requirement of Secure. Also note that Chrome devtools now have improved filtering and highlighting of problems with cookies in the Network tab and Application tab.
Front-end (client): Set the XMLHttpRequest.withCredentials flag to true, this can be achieved in different ways depending on the request-response library used:
ES6 fetch() This is the preferred method for HTTP. Use credentials: 'include'.
jQuery 1.5.1 Mentioned for legacy purposes. Use xhrFields: { withCredentials: true }.
axios As an example of a popular NPM library. Use withCredentials: true.
Proxy approach
Avoid having to do cross site (CORS) stuff altogether. You can achieve this with a proxy. Simply send all traffic to the same top level domain name and route using DNS (subdomain) and/or load balancing. With Nginx this is relatively little effort.
This approach is a perfect marriage with JAMStack. JAMStack dictates API and Webapp code to be completely decoupled by design. More and more users block 3rd party cookies. If API and Webapp can easily be served on the same host, the 3rd party problem (cross site / CORS) dissolves. Read about JAMStack here or here.
Sidenote
It turned out that Chrome won't set the cookie if the domain contains a port. Setting it for localhost (without port) is not a problem. Many thanks to Erwin for this tip!
Note for Chrome Browser released in 2020.
A future release of Chrome will only deliver cookies with cross-site
requests if they are set with SameSite=None and Secure.
So if your backend server does not set SameSite=None, Chrome will use SameSite=Lax by default and will not use this cookie with { withCredentials: true } requests.
More info https://www.chromium.org/updates/same-site.
Firefox and Edge developers also want to release this feature in the future.
Spec found here: https://datatracker.ietf.org/doc/html/draft-west-cookie-incrementalism-01#page-8
In order for the client to be able to read cookies from cross-origin requests, you need to have:
All responses from the server need to have the following in their header:
Access-Control-Allow-Credentials: true
The client needs to send all requests with withCredentials: true option
In my implementation with Angular 7 and Spring Boot, I achieved that with the following:
Server-side:
#CrossOrigin(origins = "http://my-cross-origin-url.com", allowCredentials = "true")
#Controller
#RequestMapping(path = "/something")
public class SomethingController {
...
}
The origins = "http://my-cross-origin-url.com" part will add Access-Control-Allow-Origin: http://my-cross-origin-url.com to every server's response header
The allowCredentials = "true" part will add Access-Control-Allow-Credentials: true to every server's response header, which is what we need in order for the client to read the cookies
Client-side:
import { HttpInterceptor, HttpXsrfTokenExtractor, HttpRequest, HttpHandler, HttpEvent } from "#angular/common/http";
import { Injectable } from "#angular/core";
import { Observable } from 'rxjs';
#Injectable()
export class CustomHttpInterceptor implements HttpInterceptor {
constructor(private tokenExtractor: HttpXsrfTokenExtractor) {
}
intercept(req: HttpRequest<any>, next: HttpHandler): Observable<HttpEvent<any>> {
// send request with credential options in order to be able to read cross-origin cookies
req = req.clone({ withCredentials: true });
// return XSRF-TOKEN in each request's header (anti-CSRF security)
const headerName = 'X-XSRF-TOKEN';
let token = this.tokenExtractor.getToken() as string;
if (token !== null && !req.headers.has(headerName)) {
req = req.clone({ headers: req.headers.set(headerName, token) });
}
return next.handle(req);
}
}
With this class you actually inject additional stuff to all your request.
The first part req = req.clone({ withCredentials: true });, is what you need in order to send each request with withCredentials: true option. This practically means that an OPTION request will be send first, so that you get your cookies and the authorization token among them, before sending the actual POST/PUT/DELETE requests, which need this token attached to them (in the header), in order for the server to verify and execute the request.
The second part is the one that specifically handles an anti-CSRF token for all requests. Reads it from the cookie when needed and writes it in the header of every request.
The desired result is something like this:
For express, upgrade your express library to 4.17.1 which is the latest stable version. Then;
In CorsOption: Set origin to your localhost url or your frontend production url and credentials to true
e.g
const corsOptions = {
origin: config.get("origin"),
credentials: true,
};
I set my origin dynamically using config npm module.
Then , in res.cookie:
For localhost: you do not need to set sameSite and secure option at all, you can set httpOnly to true for http cookie to prevent XSS attack and other useful options depending on your use case.
For production environment, you need to set sameSite to none for cross-origin request and secure to true. Remember sameSite works with express latest version only as at now and latest chrome version only set cookie over https, thus the need for secure option.
Here is how I made mine dynamic
res
.cookie("access_token", token, {
httpOnly: true,
sameSite: app.get("env") === "development" ? true : "none",
secure: app.get("env") === "development" ? false : true,
})
Pim's answer is very helpful. In my case, I have to use
Expires / Max-Age: "Session"
If it is a dateTime, even it is not expired, it still won't send the cookie to the backend:
Expires / Max-Age: "Thu, 21 May 2020 09:00:34 GMT"
Hope it is helpful for future people who may meet same issue.
In the latest chrome standard, if CORS requests to bring cookies, it must turn on samesite = none and secure, and the back-end domain name must turn on HTTPS,
frontend
`await axios.post(`your api`, data,{
withCredentials:true,
})
await axios.get(`your api`,{
withCredentials:true,
});`
backend
var corsOptions = {
origin: 'http://localhost:3000', //frontend url
credentials: true}
app.use(cors(corsOptions));
const token=jwt.sign({_id:user_id},process.env.JWT_SECRET,{expiresIn:"7d"});
res.cookie("token",token,{httpOnly:true});
hope it will work.
After more then a day of trying all your suggestions and many more, I surrender.
Chrome just does not accept my cross domain cookies on localhost.
No errors, just silently ignored.
I want to have http only cookies to safer store a token.
So for localhost a proxy sounds like the best way around this. I haven't really tried that.
What I ended up doing, maybe it helps someone.
Backend (node/express/typescript)
set cookie as you normally would
res.status(200).cookie("token", token, cookieOptions)
make a work around for localhost
// if origin localhost
response.setHeader("X-Set-Cookie", response.getHeader("set-cookie") ?? "");
Allow x-set-cookie header in cors
app.use(cors({
//...
exposedHeaders: [
"X-Set-Cookie",
//...
]
}));
Frontend (Axios)
On the Axios response
remove the domain= so it's defaulted.
split multiple cookies and store them locally.
// Localhost cookie work around
const xcookies = response.headers?.["x-set-cookie"];
if(xcookies !== undefined){
xcookies
.replace(/\s+Domain=[^=\s;]+;/g, "")
.split(/,\s+(?=[^=\s]+=[^=\s]+)/)
.forEach((cookie:string) => {
document.cookie = cookie.trim();
});
}
Not ideal, but I can move on with my life again.
In general this is just been made to complicated I think :-(
Update my use case maybe we can resolve it?
It's a heroku server with a custom domain.
According to this article that should be okay
https://devcenter.heroku.com/articles/cookies-and-herokuapp-com
I made an isolated test case but still no joy.
I'm pretty sure I've seen it work in FireFox before but currently nothing seems to work, besides my nasty work around.
Server Side
app.set("trust proxy", 1);
app.get("/cors-cookie", (request: Request, response: Response) => {
// http://localhost:3000
console.log("origin", request.headers?.["origin"]);
const headers = response.getHeaders();
Object.keys(headers).forEach(x => {
response.removeHeader(x);
console.log("remove header ", x, headers[x]);
});
console.log("headers", response.getHeaders());
const expiryOffset = 1*24*60*60*1000; // +1 day
const cookieOptions:CookieOptions = {
path: "/",
httpOnly: true,
sameSite: "none",
secure: true,
domain: "api.xxxx.nl",
expires: new Date(Date.now() + expiryOffset)
}
return response
.status(200)
.header("Access-Control-Allow-Credentials", "true")
.header("Access-Control-Allow-Origin", "http://localhost:3000")
.header("Access-Control-Allow-Methods", "GET,HEAD,OPTIONS,POST,PUT")
.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept")
.cookie("test-1", "_1_", cookieOptions)
.cookie("test-2", "_2_", {...cookieOptions, ...{ httpOnly: false }})
.cookie("test-3", "_3_", {...cookieOptions, ...{ domain: undefined }})
.cookie("test-4", "_4_", {...cookieOptions, ...{ domain: undefined, httpOnly: false }})
.cookie("test-5", "_5_", {...cookieOptions, ...{ domain: undefined, sameSite: "lax" }})
.cookie("test-6", "_6_", {...cookieOptions, ...{ domain: undefined, httpOnly: false, sameSite: "lax" }})
.cookie("test-7", "_7_", {...cookieOptions, ...{ domain: "localhost"}}) // Invalid domain
.cookie("test-8", "_8_", {...cookieOptions, ...{ domain: ".localhost"}}) // Invalid domain
.cookie("test-9", "_9_", {...cookieOptions, ...{ domain: "http://localhost:3000"}}) // Invalid domain
.json({
message: "cookie"
});
});
Client side
const response = await axios("https://api.xxxx.nl/cors-cookie", {
method: "get",
withCredentials: true,
headers: {
"Accept": "application/json",
"Content-Type": "application/json",
}
});
Which yields the following reponse
I see the cookies in the Network > request > cookies Tab.
But no cookies under Application > Storage > Cookies nor in document.cookie.
Pim's Answer is very helpful,
But here is an edge case I had gone through,
In my case even though I had set the Access-Control-Allow-Origin to specific origins in BE , In FE I received it as * ; which was not allowed
The problem was, some other person handled the webserver setup,
in that, there was a config to set the Access-Control-* headers which was overriding my headers set from BE application
phew.. took a while to figure it out .
So, if there is mismatches in what you set and what you received, Check your web server configs also.
Hope this would help
for me regarding the sameSite property, after enabling CORS I also add "CookieSameSite = SameSiteMode.None"
to the CookieAuthenticationOptions in the Startup file
app.UseCookieAuthentication(new CookieAuthenticationOptions
{
.....
CookieSameSite = SameSiteMode.None,
.....
}
This is an answer to "Lode Michels" from above regarding CORS cookie with the Heroku server, (and for other cloud providers, like AWS)
The reason your CORS cookie can't be set is because Heroku strip down SSL certificate at Load Balancer, so when you try to set the "secure" cookie at the server, it fails since it's no longer from the secure connection.
You can explicitally specify if the connection is secure, rather than the cookie module examining request.
https://github.com/pillarjs/cookies
with koa, add this:
ctx.cookies.secure = true;
edit: I can't comment on that answer directly due to lower than 50 reputation
This code worked for me
In the backend
Set credentials to true in your corsOptions:
const corsOptions = {
credentials: true,
};
Set cookies before sending requests:
res.cookie('token', 'xxx-xxx-xxx', {
maxAge: 24*60*60*1000, httpOnly: true,
SameSite:"None" })
In the frontend
Request in browser (using axios):
axios.post('uri/signin',
JSON.stringify({ username: 'userOne',
password: '123456'}),.
{withCredentials:true})
.the(result
=>console.log(result?.data))
.catch(err => console.log(err))