argocd-preview.yml

Comment on PRs with preview URLs and optionally trigger an ArgoCD redeploy for preview environments.

Inputs

Input	Type	Description	Required	Default
APP_URL_TEMPLATE	string	Template for the preview app URL (can include <pr_number> placeholder)	Yes	-
PR_NUMBER	number	Pull request number	Yes	-
ARGOCD_APP_NAME_TEMPLATE	string	ArgoCD app name template (may include <pr_number>)	Yes	-
ARGOCD_SYNC_PAYLOAD_TEMPLATE	string	ArgoCD sync payload template	Yes	-
ARGOCD_URL	string	URL of the Argo-CD server	Yes	-

Secrets

Secret	Description	Required	Default
ARGOCD_TOKEN	Token used to redeploy the ArgoCD app	Yes	-

Permissions

Scope	Access	Description
pull-requests	write	Required to post PR comments
contents	read	Read repository (templates)

Notes

• Both preview-comment and preview-sync jobs only trigger when the PR carries the preview label; add the label to activate preview behaviour.
• APP_URL_TEMPLATE, ARGOCD_APP_NAME_TEMPLATE, and ARGOCD_SYNC_PAYLOAD_TEMPLATE all support the <pr_number> placeholder, which is replaced at runtime with the actual PR number.
• ARGOCD_TOKEN is required to authenticate the sync API call; store it as a repository secret.
• The sync request is sent to <ARGOCD_URL>/api/v1/applications/<app-name>/sync with the provided JSON payload. Non-200 responses are reported but do not fail the workflow (the step uses continue-on-error: true).
• Useful pattern: pair with a path-filter job so previews are only rebuilt when relevant files change.

Examples

The first example shows a minimal static call with hardcoded values. The second demonstrates a complete pull-request workflow where the PR number is passed dynamically from the event payload.

Simple example

Minimal static call with all values hardcoded. The sync payload targets two specific Deployments in the preview namespace; update the resources array to match your own workloads.

jobs:
  preview:
    uses: this-is-tobi/github-workflows/.github/workflows/argocd-preview.yml@v0
    with:
      APP_URL_TEMPLATE: https://app-name.pr-<pr_number>.example.com
      PR_NUMBER: 123
      ARGOCD_APP_NAME_TEMPLATE: app-name-pr-<pr_number>
      ARGOCD_SYNC_PAYLOAD_TEMPLATE: '{"appNamespace":"argocd","prune":true,"dryRun":false,"strategy":{"hook":{"force":true}},"resources":[{"group":"apps","version":"v1","kind":"Deployment","namespace":"app-name-pr-<pr_number>","name":"app-name-pr-<pr_number>-client"},{"group":"apps","version":"v1","kind":"Deployment","namespace":"app-name-pr-<pr_number>","name":"app-name-pr-<pr_number>-server"}],"syncOptions":{"items":["Replace=true"]}}'
      ARGOCD_URL: https://argo-cd.example.com
    secrets:
      ARGOCD_TOKEN: ${{ secrets.ARGOCD_TOKEN }}

Full PR workflow integration

Typical usage inside a pull-request workflow, passing the PR number dynamically:

on:
  pull_request:
    types:
    - opened
    - reopened
    - synchronize
    - labeled

jobs:
  preview:
    uses: this-is-tobi/github-workflows/.github/workflows/argocd-preview.yml@v0
    permissions:
      pull-requests: write
      contents: read
    with:
      APP_URL_TEMPLATE: https://my-app.pr-<pr_number>.example.com
      PR_NUMBER: ${{ github.event.pull_request.number }}
      ARGOCD_APP_NAME_TEMPLATE: my-app-pr-<pr_number>
      ARGOCD_SYNC_PAYLOAD_TEMPLATE: '{"appNamespace":"argocd","prune":true,"dryRun":false,"strategy":{"hook":{"force":true}},"syncOptions":{"items":["Replace=true"]}}'
      ARGOCD_URL: https://argo-cd.example.com
    secrets:
      ARGOCD_TOKEN: ${{ secrets.ARGOCD_TOKEN }}