contrib: push Docker build-container to GitHub registry #5

	# Based on the example from https://docs.github.com/en/actions/publishing-packages/publishing-docker-images
	name: Create and publish a Docker image

	on:
	push:
	branches:
	- 'master'
	tags:
	- 'v*'
	pull_request:
	branches:
	- 'master'

	env:
	REGISTRY: ghcr.io
	IMAGE_NAME: gluon-build

	jobs:
	build-and-push-image:
	runs-on: ubuntu-latest
	permissions:
	contents: read
	packages: write
	steps:
	- name: Checkout repository
	uses: actions/checkout@v3
	- name: Log in to the Container registry
	uses: docker/login-action@v2
	with:
	registry: ${{ env.REGISTRY }}
	username: ${{ github.actor }}
	password: ${{ secrets.GITHUB_TOKEN }}
	- name: Extract metadata (tags, labels) for Docker
	id: meta
	uses: docker/metadata-action@v4
	with:
	images: ${{ env.REGISTRY }}/freifunk-gluon/${{ env.IMAGE_NAME }}
	- name: Build and push Docker image
	uses: docker/build-push-action@v4
	with:
	context: ./contrib/docker
	push: true
	tags: ${{ steps.meta.outputs.tags }}
	labels: ${{ steps.meta.outputs.labels }}

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