Pagination link headers at API are redirecting to port 80 when SSL terminated at the load balancer

Summary

Customer has noticed an issue when using the API that navigating to the second page of returned results will return a link that specifies port 80, i.e. Link: <https://gitlab.example.com:80/api/v4/projects?membership=false&order_by=created_at&......

This appears to be generated in the Pagination link header

Steps to reproduce

Configure Terminate SSL without backend SSL

Load paginated results from API request and view generated link for second page.

Example Project

This does not apply to GitLab.com (assuming because we terminate SSL at the backend).

What is the current bug behavior?

Link returns https://gitlab.example.com:80/api/v4.... which is trying to use https against port 80.

What is the expected correct behavior?

Link should be https://gitlab.example.com

Relevant logs and/or screenshots

Customer logs can be found at https://gitlab.zendesk.com/agent/tickets/114056 (Internal use only)

Output of checks

Results of GitLab environment info

Results of GitLab application Check

Possible fixes

The link is generated in pagination.rb.