I got CORS error when trying to do a request in my app in Heroku

Question

This is the error that I had faced before when requesting in localhost, and I solved it using proxy config in Angular.

So as I was using a custom proxy, I had to remove that proxy-config from my Angular app before deploying it in Heroku, because if I don't do this, the deployment app doesn't work.

This is the CORS error:

cors error

in postman the localhost request works if I nodemon the node server so I can say there's no error in my api

postman request

but if using the request given by heroku in postman I get this html response

heroku link in postman

tbh I don't know what's going on, because I'm doing a course of Angular and these errors are not supposed to appair, tkank you guys :)

Answer 1

Your web server should allow cors for you application.

If you server is written with NodeJS, take look at the Cors package

Then In NodeJS project, install it:

npm install cors

Then modify a bit your listener:

var cors = require('cors')
app.use(cors())

Make sure app.use(cors()) to be before any other middleware