DNSControl Action

Deploy your DNS configuration using GitHub Actions using DNSControl.

Usage

These are the three relevant sub commands to use with this action.

check

Run the action with the 'check' argument in order to check and validate the dnsconfig.js file. This action does not communicate with the DNS providers, hence does not require any secrets to be set.

name: Check

on: pull_request

jobs:
  check:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2

      - name: DNSControl check
        uses: koenrh/dnscontrol-action@v3
        with:
          args: check

preview

Run the action with the 'preview' argument to check what changes need to be made. It prints out what DNS records are expected to be created, modified or deleted. This action requires the secrets for the specified DNS providers.

name: Preview

on: pull_request

jobs:
  preview:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2

      - name: DNSControl preview
        uses: koenrh/dnscontrol-action@v3
        env:
          CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_API_TOKEN }}
        with:
          args: preview

This is the action you probably want to run for each branch so that proposed changes could be verified before an authorized person merges these changes into the default branch.

Pull request comment

Optionally, you could configure your GitHub Action so that the output of the 'preview' command is published as a comment to the pull request for the branch containing the changes. This saves you several clicks through the menus to get to the output logs for the preview job.

 ******************** Domain: example.com
----- Getting nameservers from: cloudflare
----- DNS Provider: cloudflare...6 corrections
#1: CREATE record: @ TXT 1 v=spf1 include:_spf.google.com -all
#2: CREATE record: @ MX 1 1  aspmx.l.google.com.
#3: CREATE record: @ MX 1 5  alt1.aspmx.l.google.com.
#4: CREATE record: @ MX 1 5  alt2.aspmx.l.google.com.
#5: CREATE record: @ MX 1 10  alt3.aspmx.l.google.com.
#6: CREATE record: @ MX 1 10  alt4.aspmx.l.google.com.
----- Registrar: none...0 corrections
Done. 6 corrections.

Provided that your GitHub Action job for 'preview' is named preview, you could use the following snippet to enable pull request comments using Unsplash's comment-on-pr GitHub Action.

- name: Preview pull request comment
  uses: unsplash/comment-on-pr@v1.2.0
  env:
    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
  with:
    msg: |
      ```
      ${{ steps.preview.outputs.output }}
      ```      
    check_for_duplicate_msg: true

push

Run the action with the 'push' arugment to publish the changes to the specified DNS providers.

Running the action with the 'push' argument will publish the changes with the specified DNS providers. The example workflow depicted below contains a filtering pattern so that it only runs on the default branch.

name: Push

on:
  push:
    branches:
      - main

jobs:
  push:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2

      - name: DNSControl push
        uses: koenrh/dnscontrol-action@v3
        env:
          CLOUDFLARE_API_TOKEN: ${{ secrets.CLOUDFLARE_API_TOKEN }}
        with:
          args: push

Credentials

Depending on the DNS providers that are used, this action requires credentials to be set. These secrets can be configured through a file named creds.json. You should not add secrets as plaintext to this file, but use GitHub Actions encrypted secrets instead. These encrypted secrets are exposed at runtime as environment variables. See the DNSControl Service Providers documentation for details.

To follow the Cloudflare example, add an encrypted secret named CLOUDFLARE_API_TOKEN and then define the creds.json file as follows.

{
  "cloudflare":{
    "apitoken": "$CLOUDFLARE_API_TOKEN"
  }
}