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## Summary This PR adds a new domain modifier `IGNORE_EXTERNAL_DNS()` that automatically detects and ignores DNS records managed by Kubernetes [external-dns](https://github.com/kubernetes-sigs/external-dns) controller. **Related Issue:** This addresses the feature request discussed in StackExchange/dnscontrol#935 (Idea: Ownership system), where @tlimoncelli indicated openness to accepting a PR for this functionality. ## Problem When running DNSControl alongside Kubernetes external-dns, users face a challenge: - **external-dns** dynamically creates DNS records based on Kubernetes Ingress/Service resources - Users cannot use `IGNORE()` because they cannot predict which record names external-dns will create - Using `NO_PURGE()` is too broad - it prevents DNSControl from cleaning up any orphaned records The fundamental issue is that `IGNORE()` requires static patterns known at config-time, but external-dns creates records dynamically at runtime. ## Solution `IGNORE_EXTERNAL_DNS()` solves this by detecting external-dns managed records at runtime: ```javascript D("example.com", REG_CHANGEME, DnsProvider(DSP_MY_PROVIDER), IGNORE_EXTERNAL_DNS(), // Automatically ignore external-dns managed records A("@", "1.2.3.4"), CNAME("www", "@") ); ``` ### How It Works external-dns uses a TXT record registry to track ownership. For each managed record, it creates a TXT record like: - `a-myapp.example.com` → TXT containing `heritage=external-dns,external-dns/owner=...` - `cname-api.example.com` → TXT containing `heritage=external-dns,external-dns/owner=...` This PR: 1. Scans existing TXT records for the `heritage=external-dns` marker 2. Parses the TXT record name prefix (e.g., `a-`, `cname-`) to determine the managed record type 3. Automatically adds those records to the ignore list during diff operations ## Changes | File | Purpose | |------|---------| | `models/domain.go` | Add `IgnoreExternalDNS` field to DomainConfig | | `pkg/js/helpers.js` | Add `IGNORE_EXTERNAL_DNS()` JavaScript helper | | `pkg/diff2/externaldns.go` | Core detection logic for external-dns TXT records | | `pkg/diff2/externaldns_test.go` | Unit tests for detection logic | | `pkg/diff2/handsoff.go` | Integrate external-dns detection into handsoff() | | `pkg/diff2/diff2.go` | Pass IgnoreExternalDNS flag to handsoff() | | `commands/types/dnscontrol.d.ts` | TypeScript definitions for IDE support | | `documentation/.../IGNORE_EXTERNAL_DNS.md` | User documentation | ## Design Philosophy This follows DNSControl's pattern of convenience builders (like `M365_BUILDER`, `SPF_BUILDER`, `DKIM_BUILDER`) that make complex operations simple. Just as those builders abstract away implementation details, `IGNORE_EXTERNAL_DNS()` abstracts away the complexity of detecting external-dns managed records. ## Testing All unit tests pass: ``` go test ./pkg/diff2/... -v # Tests detection logic go test ./pkg/js/... # Tests JS helpers go build ./... # Builds successfully ``` ## Caveats Documented - Only supports TXT registry (the default for external-dns) - Requires external-dns to use default naming conventions - May need updates if external-dns changes its registry format --------- Co-authored-by: Tom Limoncelli <6293917+tlimoncelli@users.noreply.github.com> |
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| .. | ||
| dns.go | ||
| dns_test.go | ||
| dnsrr.go | ||
| domain.go | ||
| provider.go | ||
| quotes.go | ||
| quotes_test.go | ||
| rawrecord.go | ||
| record.go | ||
| record_test.go | ||
| recorddb.go | ||
| recordtype.go | ||
| t_caa.go | ||
| t_dnskey.go | ||
| t_ds.go | ||
| t_loc.go | ||
| t_mx.go | ||
| t_naptr.go | ||
| t_parse.go | ||
| t_smimea.go | ||
| t_soa.go | ||
| t_srv.go | ||
| t_sshfp.go | ||
| t_svcb.go | ||
| t_tlsa.go | ||
| t_txt.go | ||
| target.go | ||
| tdwarn.go | ||
| tonameservers_test.go | ||
| unknown.go | ||
| unmanaged.go | ||