CORS issue with Vue.js and Nodejs - node.js

I used vuejs with nodejs, with the vue client address http://localhost:8000, the nodejs server addresses http://localhost:3000.
When calling api, I get cors error CORS preflight channel did not succeed request headers
request
Access-Control-Request-Headers: content-type
Access-Control-Request-Method: POST
Host:localhost: 3000
Origin:http://localhost: 8000
response
Access-Control-Allow-Headers: Origin, X-Requested-With, Accept,content-type
Access-Control-Allow-Methods: POST, GET, OPTIONS, DELETE, PUT,PATH
Access-Control-Allow-Origin: *
Access-Control-Max-Age: 86400
Content-Type:application/json; charset=utf-8
error in response is NS_ERROR_DOM_BAD_URI

If you use expressjs you can simply use nodejs cors lib to enable CORS in your node server.
I strongly advise you to activate it only for dev purposes :
var cors = require('cors')
if (NODE_ENV !== 'production') {
app.use(cors())
}

Related

Fail to redirect from localhost express server because of CORS preflight

I have 3 servers running on my machine:
A. port 5000
B. port 8080 (serving a react application using CREATE REACT APP)
C. port 54000
I enter the react application on server B. Then I make a REST API call for server A. Server A responds with a redirect response to url: localhost:54000 (which is server C). Then, server C handles this, and redirect also back to server B.
This makes an error in the last redirection. First one succeeds, second one does not.
I get the following error:
Access to XMLHttpRequest at 'http://localhost:8080'
(redirected from 'http://localhost:5000/user/auth/auth?port=54000')
from origin 'http://localhost:8080' has been blocked by CORS policy:
Response to preflight request doesn't pass access control check:
Redirect is not allowed for a preflight request.
The server C is Nodejs one with Express configured:
app.use((_: express.Request, res: express.Response, next: express.NextFunction) => {
res.setHeader('Access-Control-Allow-Origin', '*');
res.setHeader(
'Access-Control-Allow-Headers',
'Origin, X-Requested-With, Content-Type, Accept, Authorization',
);
res.setHeader('Access-Control-Allow-Methods', 'OPTIONS, GET');
next();
});
Could some one tell why do I get this error?
By the way the other server is static one (but served by create react app).
I think the problem resides in the CRA project. So I applied CRACO with the following config for webpack:
webpack: {
configure: {
devServer: {
headers: {
'Access-Control-Allow-Origin': '*',
},
},
},
},
But it didn't help.
My server A is a NestJS application configured with:
app.enableCors({ origin: '*' });

axios+node.js+cors : even OPTIONS requests don't reach the server

I use the follow first middleware.Due to the token header, the first request to the server is OPTIONS request.For some reason, after reload both the client and server sides, SOMETIMES non-deterministically the request can reach to 'console.log("C")' and send status 200.
app.use(function(req, res, next) {
console.log("A")
res.setHeader("Access-Control-Allow-Origin", "*");
res.setHeader("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, token");
res.header('Access-Control-Max-Age', String(60 * 60 * 24 * 365));
console.log("B")
if(req.method === 'OPTIONS'){
console.log("C")
res.sendStatus(200);
return res;
}
console.log("D")
next();
});
But subsequent GET or POST requests don't pass because of the message:
...has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
But if to use curl:
curl -I -X OPTIONS http://127.0.0.1:3003/handler
I always get a normal response, which shows all the necessary headers for CORS
HTTP/1.1 200 OK
X-Powered-By: Express
Access-Control-Allow-Origin: *
Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept, token
Access-Control-Max-Age: 31536000
Content-Type: text/plain; charset=utf-8
Content-Length: 2
ETag: W/"2-nOO9QiTIwXgNtWtBJezz8kv3SLc"
Date: Sat, 28 Mar 2020 07:24:18 GMT
Connection: keep-alive
With GET, POST requests in a similar way, everything is fine through the curl. But through the browser (using axios) it does not work. Again, it sounds crazy, but sometimes I correct / reload something, the request may even be successful, but when I pull the next handler, for example, / handler2, everything falls again.
Client:
axios.defaults.baseURL = "http://127.0.0.1:3003";
axios.defaults.headers.common["token"] = window.localStorage.token;
window.axios = axios;
axios.post("/user/handler", postData).then(...).catch(...);
Please, don't say about app.use(cors()) or app.options(...) ))
I'm sitting on it already God knows how much...𝗜 tried everything possible. But I think the problem because of the client, but not the server...In the end, for curl it works.
My standard token size is 8 KB, but in Node.js --max-http-header-size is also 8 KB.
To fix this you need to write in package.json:
"scripts": {
"start": "NODE_OPTIONS=--max-http-header-size={YOUR HEADER SIZE} ts-node src/index.ts",
"watch": "nodemon"
},
(It was non-deterministic due to the fact that the token size could be slightly less than 8 KB sometimes, maybe)
If the request is working fine with curl then I think the request header is being modified by some extensions in your browser.
Try opening your client web application in incognito mode ctrl+shift+p in mozilla firefox and ctrl+shift+n in Chrome browser and Test again.
You will get the same response as given by cur if the problem is due to any extension in your browser.

Node/ Angular CORS issue [duplicate]

This question already has answers here:
Why doesn't adding CORS headers to an OPTIONS route allow browsers to access my API?
(36 answers)
Closed 3 years ago.
so I am having this weird issue. I have an application with Node/Angular hosted on the server, working on the same port. But only on one page, there is a CORS error.
So far, I have added allowed CORS before the routes in the app.js.
CODE:
const apiRoutes = require("./routes/api");
app.use((req, res, next) => {
res.header("Access-Control-Allow-Origin", "*");
res.header(
"Access-Control-Allow-Headers",
"Content-Type, Authorization, Content-Length, X-Requested-With, cache-control"
);
res.setHeader(
"Access-Control-Allow-Methods",
"GET,POST,PATCH,DELETE,OPTIONS,PUT"
);
next();
})
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use('/uploads', express.static(path.join(__dirname, './uploads')));
app.use('/api', apiRoutes);
I have also used the cors npm package and allowed it with that as well, but still no luck.
The request parameters of getting the same image from the same directory are attached.
Response param when the image is accessed on page 1
Response param when the same image is blocked CORS
Image for error
EDIT:
const cors = require('cors');
app.use(cors());
app.options('*', cors());
I have also used this, but it doesn't work either.
Request from same origin is getting blocked,
Access to image at 'https://www.pay2mate.com/uploads/1579836295281-Affinity_Logo.png' from origin 'https://pay2mate.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.
Based on your error;
Access to image at
'https://www.pay2mate.com/uploads/1579836295281-Affinity_Logo.png'
from origin 'https://pay2mate.com' has been blocked by CORS policy: No
'Access-Control-Allow-Origin' header is present on the requested
resource.
You may have confused the difference between your NodeJS API and the web server itself.
As your code shows the image you are requesting is being served by Apache (the web server) and not by your NodeJS API;
URL: https://www.pay2mate.com/uploads/1579836295281-Affinity_Logo.png
server: Apache
accept-ranges: bytes
content-length: 5774
content-type: image/png
date: Mon, 17 Feb 2020 01:41:59 GMT
etag: "69c3450-168e-59cda4d2ef8f3"
last-modified: Fri, 24 Jan 2020 03:24:55 GMT
status: 200
You will either need to direct all requests to your API in your .htaccess file regardless of whether the physical file exists and then stream the file through your API.
Or, you could update your .htaccess file to add this header for you which will then appear on file requests (if you want this wide open like your example);
<IfModule mod_headers.c>
Header set Access-Control-Allow-Origin "*"
</IfModule>
You can read more about this here; https://enable-cors.org/server_apache.html
If this does not work. Please post more information about your hosting server configuration & the contents of your current .htaccess file

Angular2, NodeJs: Got an error "net::ERR_CONNECTION_REFUSED" when run onthe localhost

I try to run my Angular 2 app and it's backend app (node.js) both on the localhost and get an error in browser's console:
There are no errors in the backend app:
I used this code in the backend app to avoid CORS error:
app.use(function * (next) {
this.response.set('Access-Control-Allow-Methods', 'GET, POST, PUT, DELETE');
this.response.set('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept');
this.response.set('Access-Control-Allow-Origin', '*');
yield * next;
});
It seems to me the problem is related to the frontend app (zone.js may be?)
How can I solve this problem?
update: the same error after fixing https -> http

Fetch API cannot load ... No 'Access-Control-Allow-Origin' header

I got
a rest api deployed on heroku
a react app deployed on heroku
the react app tries to get data from the rest api using whatwg-fetch.
var header = {"Content-Type": "multipart/form-data", 'Origin': 'https://foo.bar', 'Access-Control-Request-Method': 'GET', 'Access-Control-Request-Headers': 'X-Requested-With'};
var options = {method: 'GET', credentials: 'include', headers: header};
fetch('https://myrest.api/foo', options)...
But I can't get any data, it say's
Fetch API cannot load https://foo.bar.
No 'Access-Control-Allow-Origin' header is present on the requested resource.
Origin 'https://foo.bar' is therefore not allowed access.
The response had HTTP status code 403.
If an opaque response serves your needs, set the request's mode to 'no-cors'
to fetch the resource with CORS disabled.
When I try to get the data with curl it works
curl -H "Origin: https://foo.bar" \
-H "Access-Control-Request-Method: GET" \
-H "Access-Control-Request-Headers: X-Requested-With" \
-X GET --verbose https://myrest.api/foo -D header.txt
and the response header (from the curl command)
HTTP/1.1 200
Server: Cowboy
Connection: keep-alive
Access-Control-Allow-Origin: https://foo.bar
Vary: Origin
Access-Control-Allow-Credentials: true
Content-Type: application/json;charset=UTF-8
Transfer-Encoding: chunked
Date: Fri, 09 Dec 2016 23:52:57 GMT
Via: 1.1 vegur
Cors is enabled in the spring boot application via #CrossOrigin
Thanks in advance
Best Regards
It seems that you are trying to access from one domain https://foo.bar into another domain at https://myrest.api and that is the reason for that error.
You have 2 options:
1) Merge this 2 apps into one single domain on Heruko, React and the Api apps will be under https://foo.bar domain for example and that will work for you.
2) Allow the client app domain at https://foo.bar to access into your api domain at https://myrest.api by adding "Access-Control-Allow-Origin" header into the api app:
app.use(function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
next();
});

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