Please expose keepAliveTimeout and headersTimeout without requiring a custom server

[tabuchid]

Describe the feature you'd like to request

When deploying behind a load balancer its good to configure the application server with a longer timeout than the load balancer. See AWS ALB reccomendation

We also recommend that you configure the idle timeout of your application to be larger than the idle timeout configured for the load balancer.

AWS defaults a ALB to a 60 second idle timeout so it would be desirable to configure next to have a 61 second timeout.

It looks like this has been discussed in a few places with little to no response from the maintainers:

• AWS ECS & ALB & CloudFront. sometimes happed status code 502 #16544
• Is there a way to modify the keepAliveTimeout without using a custom server? #19618
• Allow a configurable keep alive timeout in next config #22204

Here is a discussion of a similar issue in node. nodejs/node#27363
and two blogs about people hitting similar issues with ALB's generating 502s using express servers where the solution was to increase the keepAliveTimeout.

• https://adamcrowder.net/posts/node-express-api-and-aws-alb-502/
• https://shuheikagawa.com/blog/2019/04/25/keep-alive-timeout/

Describe the solution you'd like

Allow setting keepAliveTimeout and headersTimeout.

Describe alternatives you've considered

Ugly hacks

We are doing something similar to patch, just an awk on the bundle after build. As patch replaces the whole file (IIRC) it’s more likely to break things than a regex search and insert.

#19618 (comment)

We're using patch-package to fix this issue, please make server.keepAliveTimeout a next.js settings 🙏🏻

#19618 (comment)

or setting the ALB/ELB to a timeout of 4 seconds

Heya the only solution I was able to find was to modify the IdleTimeout on the AWS ELB to be 4 seconds, i.e 1 second less than node's default 5 seconds.

#16544 (comment)