Streamline when CI checks are run. #628

	name: Build and deploy Docker image

	on:
	push:
	branches:
	- 'main'
	release:
	types: [created]
	pull_request:

	jobs:
	docker:
	runs-on: ubuntu-latest
	steps:
	- name: Cancel Previous Runs
	uses: styfle/cancel-workflow-action@0.11.0
	with:
	access_token: ${{ secrets.GITHUB_TOKEN }}
	- name: Checkout
	uses: actions/checkout@v3
	with:
	submodules: true
	fetch-depth: 0

	-
	name: Set up QEMU
	uses: docker/setup-qemu-action@v2
	-
	name: Set up Docker Buildx
	uses: docker/setup-buildx-action@v2
	-
	name: Login to DockerHub
	if: github.event_name == 'release' \|\| github.ref == 'refs/heads/main'
	uses: docker/login-action@v2
	with:
	username: ${{ secrets.DOCKER_USERNAME }}
	password: ${{ secrets.DOCKER_ACCESS_TOKEN }}
	-
	name: Build and push stable release
	if: github.event_name == 'release'
	id: docker_build_release
	uses: docker/build-push-action@v4
	with:
	push: true
	tags: molpopgen/fwdpy11:latest, molpopgen/fwdpy11:${{ github.event.release.tag_name }}
	file: deployment/docker/Dockerfile
	context: .
	-
	name: Build and push from main
	if: github.ref == 'refs/heads/main'
	id: docker_bfild_main
	uses: docker/build-push-action@v4
	with:
	push: true
	tags: molpopgen/fwdpy11:latest
	file: deployment/docker/Dockerfile
	context: .
	-
	name: Build image
	if: github.event_name == 'pull_request'
	id: docker_build_pull_request
	uses: docker/build-push-action@v4
	with:
	push: false
	tags: molpopgen/fwdpy11:stable
	file: deployment/docker/Dockerfile
	context: .
	-
	name: Image digest
	run: echo ${{ steps.docker_build.outputs.digest }}

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