Build and push #259

	# This is a GitHub workflow defining a set of jobs with a set of steps.
	# ref: https://docs.github.com/en/free-pro-team@latest/actions/reference/workflow-syntax-for-github-actions
	#
	name: Build and push

	on:
	schedule:
	- cron: "0 0 * * " # https://crontab.guru/#0_0___
	push:
	branches: ["main"]
	tags: ["**"]
	workflow_dispatch:

	defaults:
	run:
	shell: bash

	jobs:
	build-and-push:
	runs-on: ubuntu-20.04
	steps:
	- uses: actions/checkout@v2
	- name: Setup push rights to Docker Hub
	# This was setup by...
	# 1. Creating a Docker Hub service account "jupyterhubbot"
	# 2. Making the account part of the "bots" team, and granting that team
	# permissions to push to the relevant images:
	# https://hub.docker.com/orgs/jupyterhub/teams/bots/permissions
	# 3. Registering the username and password as a secret for this repo:
	# https://github.com/jupyterhub/zero-to-jupyterhub-k8s/settings/secrets/actions
	#
	run: \|
	docker login -u "${{ secrets.DOCKER_USERNAME }}" -p "${{ secrets.DOCKER_PASSWORD }}"
	- name: Build and push
	run: \|
	if [[ $GITHUB_REF != refs/tags/* ]]; then
	docker build . \
	--tag jupyterhub/binderhub-ci-repos_minimal-dockerfile:latest
	docker push jupyterhub/binderhub-ci-repos_minimal-dockerfile:latest
	else
	docker build . \
	--tag jupyterhub/binderhub-ci-repos_minimal-dockerfile:latest \
	--tag jupyterhub/binderhub-ci-repos_minimal-dockerfile:${GITHUB_REF:10}
	docker push jupyterhub/binderhub-ci-repos_minimal-dockerfile:latest
	docker push jupyterhub/binderhub-ci-repos_minimal-dockerfile:${GITHUB_REF:10}
	fi

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