Workspaces not working for public GDK

MR: Pending

Description

Following https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/howto/public_gdk.md to make a public GDK results in the project.http_url_to_repo and Gitlab::Routing.url_helpers.root_url to resolve to incorrect port(3000 instead of 443) which creates problems(e.g. project cannot be cloned and thus workspace fails).

This problem was noticed while testing Set and use fields for workspace sudo access (!163888 - merged) .

Steps to reproduce

1. Install GDK - https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/index.md#one-line-installation
2. Follow local network binding guide for 172.16.123.1 - https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/index.md#one-line-installation
3. Setup the gdk.yml

   ---
   gitlab_k8s_agent:
     enabled: true
   listen_address: 172.16.123.1
   gitlab:
     rails:
       hostname: 'gitlab.example.com'
       allowed_hosts:
       - 'gitlab.example.com'
   vite:
     enabled: true
   webpack:
     enabled: false

4. Expose gdk publically - https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/howto/public_gdk.md

   cat >Caddyfile <<EOL
   gitlab.example.com {
     reverse_proxy 172.16.123.1:3000
   }
   EOL

5. Browse GitLab instance. You would be able to correctly browse through group hierarchies. However, when creating a workspace, the project.http_url_to_repo and Gitlab::Routing.url_helpers.root_url return http://gitlab.example.com:3000 instead of https://gitlab.example.com.

Acceptance Criteria

• Identify if this is a problem with how GDK is setup. If yes, update the instructions in https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/howto/public_gdk.md to fix it. If not, fix the problem in the code.

Technical Requirements

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Impact Assessment

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User Story

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