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ExternalDNS is a Kubernetes plugin for automating DNS record management for Kubernetes resources. By default, Kubernetes only handles internal cluster DNS. ExternalDNS delegates DNS record synchronization to external providers (e.g., SakuraCloud, AWS Route 53, etc.).

This project implements a Webhook Provider for SakuraCloud, allowing ExternalDNS to manage SakuraCloud DNS zones via standard webhook calls. It fully adheres to the official ExternalDNS Webhook Provider specification, enabling seamless integration into any existing ExternalDNS deployment. For more details, see the official documentation: kubernetes-sigs/external-dns.

• Leverages sacloud/iaas-api-go and sacloud/iaas-service-go SDKs
• Full Webhook Provider compliance with ExternalDNS specs
• Support for ALIAS records, TXT registry, and custom endpoint adjustment
• Minimal, container-friendly deployment (Helm Chart support coming)
• Comprehensive unit tests and CI/CD workflows

• Architectures: amd64, arm64
• Kubernetes >=1.20
• ExternalDNS versions up to v0.18.0

• SakuraCloud API Token & Secret
• Existing DNS Zone in SakuraCloud

Download pre-built binaries or Docker images from Releases.

Executes:

1. Delete existing test resources
2. Deploy Webhook Provider
3. Deploy ExternalDNS Controller
4. Deploy sample app and Ingress rules

Usage:

1. Update the parameters at the top of example/reset-and-deploy.sh, including the SakuraCloud API Token, Secret, and DNS Zone name. Then update the sample app’s target accordingly.

• You can edit the environment variable assignments directly in the script header.
• Ensure your Kubernetes cluster is properly configured and accessible.

2. From the project root directory, run:

bash example/reset-and-deploy.sh

3. The script will sequentially tear down and re-deploy all resources, printing detailed logs for each step.
4. Upon completion, verify the deployed resources, for example:

kubectl get pod -n <namespace>
kubectl get ingress -n <namespace>

sequenceDiagram
  participant C as External-DNS Controller
  participant W as Webhook Provider
  participant S as SakuraCloud DNS SDK

  C->>W: GET /records
  W-->>C: 200 OK + []

  C->>W: POST /adjustendpoints
  W-->>C: 200 OK + []

  C->>W: POST /records (create)
  W->>S: CreateRecord/Alias/TXT + Delete
  S-->>W: success
  W-->>C: 204 No Content

  Note over C,W: Subsequent sync cycles...

sequenceDiagram
  participant C as Controller
  participant W as WebhookProvider
  participant S as SakuraCloudAPI

  C->>W: GET /records
  W->>S: ListRecords()
  S-->>W: DNS records list
  W-->>C: Endpoint list

  C->>W: POST /adjustendpoints []
  W-->>C: []

  C->>W: POST /records (create alias)
  W->>S: ApplyChanges(ALIAS + TXT)
  S-->>W: success
  W-->>C: 204 No Content

  C->>W: POST /adjustendpoints []
  W-->>C: []

  C->>W: POST /records (delete alias)
  W->>S: ApplyChanges(delete ALIAS + TXT)
  S-->>W: success
  W-->>C: 204 No Content

• Only supports A, CNAME, & TXT record types
• Currently SakuraCloud does not support AAAA or MX via this webhook
• SakuraCloud DNS API only supports a single target (RData) per DNS record. Multiple targets (e.g. multiple A or TXT values for the same name) are not supported; each must be a separate record.

external-dns-sacloud-webhook Copyright (C) 2025- The sacloud/external-dns-sacloud-webhook authors. This project is published under Apache 2.0 License.