Prepare KarlDNS production deployment

karldns/dns/base.py

@@ -0,0 +1,83 @@
+from __future__ import annotations
+
+from ..models import UpdateResult
+from ..settings import DdnsSettings
+
+SUPPORTED_DNS_PROVIDERS = {"", "cloudflare", "rfc2136"}
+
+
+class DnsProviderError(RuntimeError):
+    """Raised for expected DNS provider publish/delete failures."""
+
+
+class DnsReconciliationError(DnsProviderError):
+    """Raised when provider read-back does not match the requested DNS state."""
+
+
+class DnsConfigurationError(RuntimeError):
+    """Raised when DNS provider settings are invalid at startup."""
+
+
+def publish_dns(result: UpdateResult, settings: DdnsSettings) -> None:
+    validate_dns_provider_settings(settings)
+    provider = _normalized_provider(settings)
+    if provider == "cloudflare":
+        from .cloudflare import publish_cloudflare
+
+        publish_cloudflare(result, settings)
+        return
+    if settings.rfc2136_server or provider == "rfc2136":
+        from .rfc2136 import publish_rfc2136
+
+        publish_rfc2136(result, settings)
+        return
+    if settings.require_dns_provider:
+        raise DnsProviderError("DNS provider is required but not configured")
+
+
+def delete_dns_records(hostname: str, settings: DdnsSettings) -> None:
+    validate_dns_provider_settings(settings)
+    provider = _normalized_provider(settings)
+    if provider == "cloudflare":
+        from .cloudflare import delete_cloudflare_records
+
+        delete_cloudflare_records(hostname, settings)
+        return
+    if settings.rfc2136_server or provider == "rfc2136":
+        from .rfc2136 import delete_rfc2136_records
+
+        delete_rfc2136_records(hostname, settings)
+        return
+    if settings.require_dns_provider:
+        raise DnsProviderError("DNS provider is required but not configured")
+
+
+def dns_backend_configured(settings: DdnsSettings) -> bool:
+    validate_dns_provider_settings(settings)
+    provider = _normalized_provider(settings)
+    return provider == "cloudflare" or provider == "rfc2136" or bool(settings.rfc2136_server)
+
+
+def validate_dns_provider_settings(settings: DdnsSettings) -> None:
+    provider = _normalized_provider(settings)
+    if provider not in SUPPORTED_DNS_PROVIDERS:
+        raise DnsConfigurationError(f"Unsupported DDNS_DNS_PROVIDER: {settings.dns_provider}")
+    if not settings.require_dns_provider:
+        return
+    if provider == "cloudflare":
+        if not settings.cloudflare_api_token or not settings.cloudflare_zone_id:
+            raise DnsConfigurationError(
+                "DDNS_CLOUDFLARE_API_TOKEN and DDNS_CLOUDFLARE_ZONE_ID are required when DDNS_DNS_PROVIDER=cloudflare"
+            )
+        return
+    if provider == "rfc2136" or settings.rfc2136_server:
+        if not settings.rfc2136_server or not settings.rfc2136_zone:
+            raise DnsConfigurationError(
+                "DDNS_RFC2136_SERVER and DDNS_RFC2136_ZONE are required when RFC2136 DNS publishing is enabled"
+            )
+        return
+    raise DnsConfigurationError("DDNS_REQUIRE_DNS_PROVIDER is set but no DNS backend is configured")
+
+
+def _normalized_provider(settings: DdnsSettings) -> str:
+    return settings.dns_provider.strip().lower()