Reported error when adding a DuckDNS provider:
TypeError: this.domains.map is not a function
at Proxy.updateDomains (models/dns_provider.js:185:37)
DnsProvider.__intraModel merges `{...DnsProvider._keyMap,
...Provider._keyMap}`, so a provider-defined field with the same name
as one of DnsProvider's own (created_by, updated_by, name,
dnsProvider, domains, id) silently overwrites it. DuckDNS defined a
`domains` field (the operator-supplied comma-separated subdomain
list), which replaced DnsProvider's `domains` relation (rel: 'many' to
Domain, populated by updateDomains()) — so `this.domains` stopped
being the array relation and became DuckDNS's raw string instead.
Rename the field to `subdomains` throughout (model, docs, tests). Add
a comment on __intraModel documenting the collision risk for future
providers, and a regression test asserting no registered provider's
_keyMap redefines one of DnsProvider's reserved field names.
DuckDNS's API is smaller than the other providers' (no list/read API,
no arbitrary sub-records, one A/AAAA + one TXT record per domain), so
domains are entered by the operator instead of auto-discovered, and
getRecords reads from public DNS since there's nothing else to query.
Documented as a free option in the README and DNS provider docs.
wmantly