fix: resolve DNS record churning caused by Records/AdjustEndpoints - #30
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…smatch Records() returned DNS names without trailing dots and SRV targets without the priority field, while AdjustEndpoints() canonicalized names with trailing dots and external-dns expected 4-part SRV targets. This mismatch caused external-dns to detect "changes" on every sync cycle, resulting in constant create/update/delete API churn. Changes: - Add trailing dot to DNSName in convertRecordToEndpoint to match AdjustEndpoints canonicalization - Reassemble SRV priority (stored as separate API field by Rackspace) into the "priority weight port target" format external-dns expects - Add table-driven tests for trailing dot, SRV format, NS/SOA filtering, TXT label parsing, domain filtering, dry run, and Records/AdjustEndpoints idempotency
AdjustEndpoints was adding trailing dots to DNS names, normalizing TTL from 0 to 300, and stripping quotes from TXT targets. These transformations created mismatches between what Records() returned and what external-dns expected, causing every record to be updated on every sync cycle. Per the external-dns webhook contract, AdjustEndpoints should be a pass-through unless provider-specific canonicalization is needed. Additionally, Records() returned one endpoint per Rackspace record, but external-dns expects one endpoint per name+type with all targets merged. Changes: - Make AdjustEndpoints a pass-through (matches BaseProvider default) - Merge records with same name+type into single multi-target endpoints - Reassemble SRV priority into the target string (Rackspace stores it as a separate API field) - Skip JSON unmarshal on non-JSON TXT record comments - Add request logging to all webhook handlers
skrobul
approved these changes
Apr 23, 2026
cardoe
approved these changes
Apr 24, 2026
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AdjustEndpoints was adding trailing dots to DNS names, normalizing TTL
from 0 to 300, and stripping quotes from TXT targets. These
transformations created mismatches between what Records() returned and
what external-dns expected, causing every record to be updated on every
sync cycle. Per the external-dns webhook contract, AdjustEndpoints
should be a pass-through unless provider-specific canonicalization is
needed.
Additionally, Records() returned one endpoint per Rackspace record, but
external-dns expects one endpoint per name+type with all targets merged.
Changes:
as a separate API field)