feat(bbb-docker): Add enable switches for **Collabora** and **Coturn** + make Collabora URL configurable

[kevinveenbirkenbach]

Summary

This MR introduces opt-in/opt-out switches for bundling Collabora and Coturn inside the BigBlueButton Docker stack. It also makes the Collabora endpoint configurable via COLLABORA_URL. With these changes, operators can either run the bundled services or disable them to use centralized services provided elsewhere in the infrastructure (e.g., via Infinito.Nexus roles).

• New env flags: ENABLE_COLLABORA, ENABLE_COTURN
• New env var: COLLABORA_URL (used by conversion scripts)
• Conditional depends_on and service blocks in the Compose template
• Updated sample.env and scripts/generate-compose

These switches are required to integrate with centralized deployments managed by Infinito.Nexus:

• BigBlueButton role: https://github.com/kevinveenbirkenbach/infinito-nexus/tree/master/roles/web-app-bigbluebutton
• Coturn service role: https://github.com/kevinveenbirkenbach/infinito-nexus/tree/master/roles/web-svc-coturn
• Collabora service role: https://github.com/kevinveenbirkenbach/infinito-nexus/tree/master/roles/web-svc-collabora

---

What changed

Compose template (docker-compose.tmpl.yml)

• bbb-web.depends_on: gated collabora with {{ if isTrue .Env.ENABLE_COLLABORA }} ... {{ end }}

• bbb-web.environment: added COLLABORA_URL with sensible default

• etherpad.depends_on: conditionally depends on collabora

• New conditional blocks:

  • Wrap entire collabora service with {{ if isTrue .Env.ENABLE_COLLABORA }} ... {{ end }}
  • Wrap entire coturn service with {{ if isTrue .Env.ENABLE_COTURN }} ... {{ end }}

Conversion scripts

• mod/bbb-web/office-convert.sh: use $COLLABORA_URL/convert-to/... instead of hardcoded https://collabora:9980/cool/...
• mod/etherpad/etherpad-export.sh: same change to use $COLLABORA_URL

Environment & generation

• sample.env: added:

  ENABLE_COLLABORA=true
  COLLABORA_URL=https://collabora:9980/cool
  ENABLE_COTURN=true
  

• scripts/generate-compose: export new flags to the templater:

  -e ENABLE_COTURN=${ENABLE_COTURN:-true} \
  -e ENABLE_COLLABORA=${ENABLE_COLLABORA:-true} \
  

---

Why

• Let operators disable embedded services and consume centralized, shared services (e.g., a site-wide Collabora/Coturn), reducing duplication and simplifying maintenance.
• Avoid hardcoded Collabora URL to support different network topologies (internal hostname, external FQDN, reverse proxy path, TLS termination variants).

---

How to use

• Bundled services (default):

  ENABLE_COLLABORA=true
  COLLABORA_URL=https://collabora:9980/cool
  ENABLE_COTURN=true
  

• External/central services:

  ENABLE_COLLABORA=false
  COLLABORA_URL=https://collabora.example.org/cool
  ENABLE_COTURN=false
  

  Ensure your external Coturn and Collabora endpoints are reachable and correctly configured.

---

Backwards compatibility

• Defaults keep previous behavior: both services remain enabled and the in-stack Collabora URL is preserved.
• Scripts now honor COLLABORA_URL. If unset, Compose injects the previous default (https://collabora:9980/cool).

---

Testing

1. Default path (embedded)

   • ENABLE_COLLABORA=true, ENABLE_COTURN=true
   • Run ./scripts/generate-compose and docker compose up -d
   • Verify services include collabora and coturn
   • Upload ODT/PPT/PDF → conversion works
   • TURN/STUN connectivity works in meetings

2. Centralized Collabora

   • ENABLE_COLLABORA=false, set COLLABORA_URL to external
   • Regenerate and start
   • Confirm no collabora service in Compose
   • Conversions call external $COLLABORA_URL

3. Centralized Coturn

   • ENABLE_COTURN=false
   • Regenerate and start
   • Confirm no coturn service in Compose
   • Verify BBB uses external TURN (env/config as per your infra)

---

Security considerations

• When pointing COLLABORA_URL to an external service, ensure TLS and trust boundaries are appropriate.
• Disabling embedded Coturn requires your external TURN to be correctly authenticated and reachable (shared secret or long-term credentials).

---

Checklist

• [x] Conditional depends_on for bbb-web and etherpad
• [x] Collabora & Coturn services gated by env flags
• [x] Conversion scripts read COLLABORA_URL
• [x] sample.env extended with new vars
• [x] scripts/generate-compose passes flags to templater
• [x] Verified defaults preserve existing behavior

---

Diff (reference)

Included in the MR: changes to docker-compose.tmpl.yml, mod/bbb-web/office-convert.sh, mod/etherpad/etherpad-export.sh, sample.env, and scripts/generate-compose as provided in the request.