Add arythmatic.cloud lms-custom-domain template

[SaiSatya16]

Description

New Service Provider template: Arythmatic LMS — custom domain (arythmatic.cloud / lms-custom-domain). It connects a customer's subdomain to their Arythmatic LMS portal by adding exactly two records: a CNAME to the Arythmatic edge (domains.lms.arythmatic.cloud) and a TXT ownership-verification record (_arythmatic-verify … arythmatic-tenant-verify=%verifycode%). Automates the same two records a customer would otherwise copy/paste by hand.

Type of change

• New template

How Has This Been Tested?

• Template functionality checked using the Online Editor (see link below)
• Template file name follows the pattern <providerId>.<serviceId>.json (arythmatic.cloud.lms-custom-domain.json)
• No logoUrl provided (optional), so the served-resource check is N/A

Checklist of common problems

• syncPubKeyDomain is set — not set; justification: this template touches only two low-risk records — a CNAME on the requested subdomain and a single ownership-verification TXT. It cannot alter MX/NS/nameservers or any zone-wide/email-affecting record, so it carries none of the hijack risk signing primarily guards against. syncRedirectDomain (below) is set to bound the synchronous redirect, and the Service Provider independently validates the redirect_uri server-side before ever building the apply URL. A signed variant (syncPubKeyDomain + _dcpubkeyv1 publication + RS256 request signing) is a planned follow-up; requesting guidance on whether unsigned is acceptable for a two-record CNAME+TXT template of this shape.
• warnPhishing is not set alongside syncPubKeyDomain — neither is set
• syncRedirectDomain is set (lms-manage.arythmatic.cloud) — the synchronous flow uses redirect_uri
• no TXT record contains SPF content — the TXT is arythmatic-tenant-verify=%verifycode%
• txtConflictMatchingMode is set on the TXT record ("All") — the verify TXT must be unique per label
• no bare-variable full TXT value — value is prefixed: arythmatic-tenant-verify=%verifycode%
• no bare variable as a full host label — hosts are fixed (@, _arythmatic-verify)
• no variable used in host to create a subdomain — uses the host parameter (hostRequired: true), not a host variable
• %host% does not appear in any host attribute
• essential/OnApply — N/A; neither record is user-modifiable without breaking the connection

Online Editor test results

hostRequired: true, so per the guidelines only a subdomain (host-set) test is required; apex test not applicable.

Editor test link(s): Test arythmatic.cloud/lms-custom-domain — acme.com / learn

[github-actions]

✅ JSON Filename Check Passed

[github-actions]

✅ JSON Schema Validation Passed

[github-actions]

Linter OK

arythmatic.cloud.lms-custom-domain.json

Level	Code	Note
info	DCTL1029	template does not have syncPubKeyDomain
info	DCTL1021	missing from iana definitions

[github-actions]

PR Description Check Passed

All required sections are filled in correctly.

Details

  OK  Type of change: 1/1 checkboxes ticked
  OK  How Has This Been Tested?: all 3 checkboxes ticked
  OK  Checklist of common problems: 9/10 checkboxes ticked
  OK  Online Editor test results: 1 link(s) found
  OK  Template coverage: all 1 template(s) covered
Labels to remove: Checklist of common problems not complete, Forged editor links, PR description incomplete, Test links missing

PR description check PASSED

[pawel-kow]

A signed variant (syncPubKeyDomain + _dcpubkeyv1 publication + RS256 request signing) is a planned follow-up;

Yes, please add it from the start. Some providers won't even onboard a template without it.
It saves review round trips as well.