In one of my projects, I’m getting issues while connecting to AWS load balancers - I have written this post to secure my studies in this regard.
The REST requests from the front end reaches the server without CORS
- without the AWS elastic load balancer and directly to the EC2 server
The REST requests breaks with the CORS errors from the front end and not reaches the server:
- with the AWS elastic load balancer and not directly to the EC2 server
- Allowed CORS in the S3 bucket, example config — done
- Allowed CORS in the back end using CORS node module — done
- Allowed CORS in the nginx proxy using the CORS headers — done
- Allow CORS on the load balancer’s front — not done
Based on my studies so far:
Requests only use the GET or POST HTTP methods. If the POST method is used, then Content-Type can only be one of the following: application/x-www-form-urlencoded, multipart/form-data, or text/plain.
Hope this helps to some extent.