image_build_push.yml

# This is a basic workflow to help you get started with Actions

name: docker image

# Controls when the action will run. Triggers the workflow on push or pull request 
# events but only for the master branch
on:
  push:
    branches: [ image-push-merge ]


# Env variable
env:
  DOCKER_USER: ${{secrets.DOCKER_USER}}
  DOCKER_PASSWORD: ${{secrets.DOCKER_PASSWORD}}

# A workflow run is made up of one or more jobs that can run sequentially or in parallel
jobs:
  # This workflow contains a single job called "build"
  build:
    # The type of runner that the job will run on
    runs-on: ubuntu-latest

    # Steps represent a sequence of tasks that will be executed as part of the job
    steps:
    # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
    - uses: actions/checkout@v2
    - name: docker login
      run: | # log into docker hub account
        docker login -u $DOCKER_USER -p $DOCKER_PASSWORD

    - name: Get current date # get the date of the build
      id: date
      run: echo "::set-output name=date::$(date +'%Y-%m-%d--%M-%S')"

    #Runs a single command using the runners shell
    - name: Run a one-line script
      run: echo running in repo ${GITHUB_REPOSITORY#*/} branch ${GITHUB_REF##*/} on ${{ steps.date.outputs.date }}

    # Runs a set of commands using the runners shell
    - name: build docker image
      run: |
        docker build -t $DOCKER_USER/${GITHUB_REPOSITORY#*/}:${GITHUB_REF##*/}_${{ steps.date.outputs.date }} .
        docker images

    - name: push docker image
      run: |
        docker push $DOCKER_USER/${GITHUB_REPOSITORY#*/}:${GITHUB_REF##*/}_${{ steps.date.outputs.date }}