Merge pull request #2124 from spechub/2119_regularly_update_Hets_dock…

…er_image

add CI job for docker publishing

.github/workflows/docker.yml

@@ -0,0 +1,70 @@
+# Build hets docker image
+name: Docker
+
+env:
+  HETS_LIB_REPO: https://github.com/spechub/Hets-lib.git
+  HETS_PPA: http://ppa.launchpad.net/hets/hets/ubuntu
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    paths:
+      - 'Docker/**'
+  # NOTE: Can be triggered via WebUI, if this file is on the _default_ branch,
+  #       only. However, triggering via Rest Api should work!
+  workflow_dispatch:
+    inputs:
+      tags:
+        description: 'Test image'
+
+# Run this workflow for the latest commit in a branch, only. I.e. if there is
+# any instance for an older commit still running, stop it and kill its jobs.
+concurrency:
+  group: pr-docker-${{ github.head_ref }}
+  cancel-in-progress: true
+
+jobs:
+
+  job_1:
+    # takes ~ ???
+    name: Publish docker image
+    # If a job doesn't get picked up for hours, the cause could be, that the
+    # specified platform is not supported anymore. In this case one will not get
+    # any hint, what's goin wrong - it just sits in the queue and wait for a
+    # runner forever (or until it gets kicked by a github cleanup job). See also
+    # https://github.com/actions/runner-images/issues/6002
+    # https://docs.github.com/en/actions/using-github-hosted-runners/about-github-hosted-runners#supported-runners-and-hardware-resources
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Dump GitHub context
+        env:
+          GITHUB_CTX: ${{ toJSON(github) }}
+          MY_ENV: ${{ toJSON(env) }}
+          RUNNER_CTX: ${{ toJSON(runner) }}
+        run: |
+          printf "github:\n$GITHUB_CTX\n"
+          printf "env:\n$MY_ENV\n"
+          printf "env:\n$RUNNER_CTX\n"
+          df -h
+          printf "Tags: ${{ github.event.inputs.tags }}\n"
+
+       # NOTE: any file mutation in the steps that precede the build step will
+       #       be ignored, including processing of the .dockerignore file since
+       #       the context is based on the Git reference.
+      - name: Docker Buildx Setup
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v4
+        with:
+          context: "{{defaultContext}}:Docker"
+          push: true
+          tags: ${{ secrets.DOCKER_HUB_USERNAME }}/hets:latest

Docker/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:18.04
+FROM ubuntu:20.04
 
 ENV LANG C.UTF-8