Merge pull request #56 from mozilla-services/MZCLD-182 #10

	---
	name: build and push to GAR
	on:
	push:
	branches:
	- main

	tags:
	- v[0-9]+.[0-9]+.[0-9]+

	jobs:
	build-and-push:
	strategy:
	matrix:
	include:
	- gcp_project_id: moz-fx-backstage-prod
	gar_repo: backstage-prod

	- gcp_project_id: moz-fx-rapid-release-mode-1cb6
	gar_repo: rapid-release-model-prod

	name: build and push
	runs-on: ubuntu-latest
	environment: build
	permissions:
	contents: read
	id-token: write

	steps:
	- id: checkout-application-repo
	uses: actions/checkout@v4
	with:
	fetch-depth: 0

	- id: set-tag
	run: \|-
	echo TAG=$(git describe --tags --abbrev=7) \|tee -a ${GITHUB_OUTPUT}

	- uses: docker/setup-buildx-action@v3

	- id: gcp-auth
	uses: google-github-actions/auth@v2
	with:
	token_format: access_token
	service_account: artifact-writer@${{ matrix.gcp_project_id }}.iam.gserviceaccount.com
	workload_identity_provider: ${{ secrets.WORKLOAD_IDENTITY_POOL_PROJECT_NUMBER }}

	- uses: docker/login-action@v3
	name: Docker login
	with:
	registry: us-docker.pkg.dev
	username: oauth2accesstoken
	password: ${{ steps.gcp-auth.outputs.access_token }}

	- id: build-and-push-backstage
	uses: docker/build-push-action@v6
	with:
	context: . # Expecting the multi-stage build from here: https://backstage.io/docs/deployment/docker/#multi-stage-build
	tags: \|
	us-docker.pkg.dev/${{ matrix.gcp_project_id }}/${{ matrix.gar_repo }}/moz-backstage-app:${{ steps.set-tag.outputs.TAG }}
	us-docker.pkg.dev/${{ matrix.gcp_project_id }}/${{ matrix.gar_repo }}/moz-backstage-app:latest

	push: true
	cache-from: type=gha
	cache-to: type=gha,mode=max

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