CORS error when calling from the client?

Question

I have a Nginx webserver in front of a Node REST API delivering JSON formatted data.

I also have a web app which consumes the above API and works fine for a majority of the requests it makes but sometimes, for certain URLs, the client gets a CORs error aka an 'Access-Control-Allow-Origin' error.

When I call the data again from the server of the web app it works fine again.

Could anyone shed some light on this issue.

I am using axios to call the API from the web app

Answer 1

You need to add CORS headers in response so that api can be accessed from browser. You can use npm cors package https://www.npmjs.com/package/cors