ExternalDNS - Midaas-webhook

ExternalDNS is a Kubernetes add-on for automatically managing Domain Name System (DNS) records on Kubernetes objects (ingress, crd, services) by using different DNS providers (aws, ovh, webhook...).

This repository use the webhook provider. This webhook is a sidecar running in the same pod as external-dns, which manage MiDaas dns records.

To use ExternalDNS with MiDaas, you need to inject TSIG on each zone you want to manage.

Kubernetes deployment

You can deploy the webhook using the following commands:

helm repo add external-dns https://kubernetes-sigs.github.io/external-dns/

1. Create the helm values file external-dns-midaas-values.yaml:

sources:
- ingress
# -- How DNS records are synchronized between sources and providers; available values are `sync` & `upsert-only`.
policy: sync
# -- Specify the registry for storing ownership and labels.
# Valid values are `txt`, `aws-sd`, `dynamodb` & `noop`.
# If `noop` midaas manage all records on zone
registry: txt
# can restrict zone
domainFilters: []
provider: 
  name: webhook
  webhook: 
    image: 
      repository: ghcr.io/titigmr/external-dns-midaas-webhook
      tag: latest
    env:
    - name: PROVIDER_DNS_ZONE_SUFFIX
      value: "dev.example.com"
    - name: PROVIDER_WS_URL
      value: https://midaas.example.com/midaas/ws
    - name: TSIG_ZONE_<TSIG_Keyname>
      value: <TSIG_Keyvalue>

2. Create helm deployment:

helm install external-dns external-dns/external-dns -f external-dns-midaas-values.yaml

Parameters references

Name	Description	Default value
API_SERVER_PORT	define the host where api listen, for all interfaces	"0.0.0.0"
API_SERVER_HOST	define the port where api listen	"8888"
API_READ_TIMEOUT	timout until read	3s
API_WRITE_TIMEOUT	timeout until write	3s
API_LOG_LEVEL	log level among DEBUG,INFO,TRACE,WARN,ERROR	INFO
PROVIDER_SKIP_TLS_VERIFY	enable tls verification	false
PROVIDER_DNS_ZONE_SUFFIX	dns zone suffix	"dev.example.com"
PROVIDER_WS_URL	webservice url	"https://midaas.example.com/midaas/ws/"
TSIG_ZONE_<TSIG_Keyname>	tsigs credentials for manipulating one or multiples zones

For example, TSIG_ZONE_d1 with PROVIDER_DNS_ZONE_SUFFIX with dev.example.com refer to the folowing zone: d1.dev.example.com

Local development

Prerequisite

Download and install on your local machine:

• make in Debian/Ubuntu distrib with

  sudo apt install build-essential

• docker
• kubectl
• kind
• helm

Usage

You can create a development stack locally with this command:

make

This target do the following target successively:

• create-cluster : create a kind cluster locally with an ingress controller configured
• deploy-MIDAAS : build, push and deploy midaas webservice mock in the cluster
• deploy-WEBHOOK : build, push and deploy external-dns with the midaas webhook in development mode. You can modify the code with hot reload.

For example, for restarting the webhook:

make deploy-WEBHOOK

Don't forget create an ingress for trigger external-dns, an example can be created with:

make create-test-ingress 

You can read the containers logs with:

make logs-webhook

or

make logs-external-dns

To clean all the components

make clean

Contributions

Commits must follow the specification of Conventional Commits, it is possible to add the VSCode extension to facilitate the creation of commits.

A PR must be made with an updated branch with the main branch in rebase (and without merge) before requesting a merge, and the merge must be requested in main.