Multi-platform images built using buildx can be copied from one registry to another without

changing the image SHA using the [tag-push-action](https://github.com/akhilerm/tag-push-action).

The following workflow will first push the image to dockerhub, run some tests using the images

and then push to quay and ghcr

name: ci

on:

push:

branches:

- 'master'

jobs:

docker:

runs-on: ubuntu-latest

steps:

-

name: Checkout

uses: actions/checkout@v2

-

name: Set up QEMU

uses: docker/setup-qemu-action@v1

-

name: Set up Docker Buildx

uses: docker/setup-buildx-action@v1

- # quay and ghcr logins for pushing image after testing

name: Login to Quay Registry

uses: docker/login-action@v1

with:

registry: quay.io

username: ${{ secrets.QUAY_USERNAME }}

password: ${{ secrets.QUAY_TOKEN }}

-

name: Login to GitHub Container Registry

uses: docker/login-action@v1

with:

registry: ghcr.io

username: ${{ github.repository_owner }}

password: ${{ secrets.GITHUB_TOKEN }}

-

name: Login to DockerHub

uses: docker/login-action@v1

with:

username: ${{ secrets.DOCKERHUB_USERNAME }}

password: ${{ secrets.DOCKERHUB_TOKEN }}

-

name: Build and push

uses: docker/build-push-action@v2

with:

context: .

platforms: linux/amd64,linux/arm64

push: true

tags: |

- # run tests using image from docker hub

name: Run Tests

run: make tests

- # copy multiplatform image from dockerhub to quay and ghcr

name: Push Image to multiple registries

uses: akhilerm/tag-push-action@v1.0.0

with:

src: docker.io/user/app:1.0.0

dst: |