deployment-dispatch-action

Composite GitHub Action that dispatches image update requests to the deployment repo and waits for the dispatched workflow to complete.

Prerequisites

The caller repository needs access to these org-level Actions credentials:

• variable: DEPLOYMENT_DISPATCHER_APP_ID
• secret: DEPLOYMENT_DISPATCHER_APP_PRIVATE_KEY

The GitHub App must be installed on the target org and repository with these repository permissions on the deployment repo:

• Actions: write
• Checks: read

This action passes an explicit workflow ref by default so gh workflow run does not need to resolve the target repo's default branch, which typically requires Contents: read.

Runner support

This action is only supported on GitHub-hosted ubuntu-22.04 and ubuntu-24.04 runners.

ubuntu-slim is not supported. Other runners are not supported either.

The action shell steps depend on the Ubuntu runner toolchain contract, including bash, jq, gh workflow run support, and GNU timeout.

Inputs

Name	Required	Default	Description
deployment-dispatcher-app-id	yes	—	GitHub App ID
deployment-dispatcher-app-private-key	yes	—	GitHub App private key
updates	yes	—	Newline-delimited image=tag pairs
owner	no	devsoc-unsw	Owner of the deployment repository
repository	no	deployment	Deployment repository name
workflow	no	dispatch-image-update.yml	Workflow file to dispatch
ref	no	dev	Git ref used when dispatching the workflow
watch-timeout-seconds	no	180	Maximum time to wait for the dispatched workflow run to finish

Update format

ghcr.io/devsoc-unsw/freerooms-backend=abc123
ghcr.io/devsoc-unsw/freerooms-frontend=abc123

One update per line. Image should be the full GHCR image name, tag should be the exact tag you just pushed.

Blank lines are ignored. Any non-empty line that is not a valid image=tag pair fails the action.

Outputs

See action.yml for outputs — they are usually not required by callers.

Examples

Single image

- name: Dispatch deployment
  uses: devsoc-unsw/deployment-dispatch-action@v1
  with:
    deployment-dispatcher-app-id: ${{ vars.DEPLOYMENT_DISPATCHER_APP_ID }}
    deployment-dispatcher-app-private-key: ${{ secrets.DEPLOYMENT_DISPATCHER_APP_PRIVATE_KEY }}
    updates: |
      ghcr.io/devsoc-unsw/freerooms-backend=${{ github.sha }}

Multiple images

- name: Dispatch deployment
  uses: devsoc-unsw/deployment-dispatch-action@v1
  with:
    deployment-dispatcher-app-id: ${{ vars.DEPLOYMENT_DISPATCHER_APP_ID }}
    deployment-dispatcher-app-private-key: ${{ secrets.DEPLOYMENT_DISPATCHER_APP_PRIVATE_KEY }}
    updates: |
      ghcr.io/devsoc-unsw/freerooms-backend=${{ github.sha }}
      ghcr.io/devsoc-unsw/freerooms-frontend=${{ github.sha }}

Custom target

- name: Dispatch deployment
  uses: devsoc-unsw/deployment-dispatch-action@v1
  with:
    deployment-dispatcher-app-id: ${{ vars.DEPLOYMENT_DISPATCHER_APP_ID }}
    deployment-dispatcher-app-private-key: ${{ secrets.DEPLOYMENT_DISPATCHER_APP_PRIVATE_KEY }}
    owner: devsoc-unsw
    repository: deployment
    workflow: dispatch-image-update.yml
    ref: dev
    updates: |
      ghcr.io/devsoc-unsw/notangles=${{ github.sha }}