name: Purge image cache

on:
  push:
    branches:
      - master
  schedule:
    - cron: '4 18 * * *'

jobs:
  purge:
    runs-on: ubuntu-18.04
    steps:

    - run: |
        IMAGE_LIST=$(curl -sL https://github.com/${GITHUB_REPOSITORY} | \
          grep -oE '<img src="https?://camo.githubusercontent.com/[^"]+' | \
          sed -e 's/<img src="//')
        echo ${IMAGE_LIST} | xargs -I % curl -sX PURGE %