replace travis with gha

Author: pietroalbini

Diff for: .github/workflows/main.yml

@@ -0,0 +1,50 @@
+---
+
+name: CI
+on:
+  push:
+    branches:
+      - master
+  pull_request: {}
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the source code
+        uses: actions/checkout@v2
+
+      - name: Run the custom linter
+        run: ./lint.sh
+
+  build:
+    name: Build images
+    runs-on: ubuntu-latest
+    needs: [lint]
+
+    # Use the same job to build all Linux-based images
+    strategy:
+      matrix:
+        image:
+          - linux
+          - linux-micro
+
+    steps:
+      - name: Checkout the source code
+        uses: actions/checkout@v2
+
+      - name: Build the Docker image
+        run: docker build -t ghcr.io/${{ github.repository }}/${{ matrix.image }}:latest ${{ matrix.image }}/
+
+      - name: Authenticate with GitHub Container Registry
+        uses: docker/login-action@v1
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+        if: github.event_name == 'push' && github.ref == 'refs/heads/master'
+
+      - name: Upload the Docker image to GitHub Container Registry
+        run: docker push ghcr.io/${{ github.repository }}/${{ matrix.image }}:latest
+        if: github.event_name == 'push' && github.ref == 'refs/heads/master'

Diff for: .travis.yml

@@ -3,11 +3,19 @@ set -euo pipefail
 IFS=$'\n\t'
 export LC_ALL=C
 
+PACKAGES_FILES=(
+    linux/packages.txt
+    linux-micro/packages.txt
+)
+
 # Ensure packages lists are sorted
-for file in packages; do
-    cat "${file}.txt" | sort -u > "/tmp/sorted-${file}.txt"
-    if ! diff -u "/tmp/sorted-${file}.txt" "${file}.txt"; then
-        echo "Lint error: ${file}.txt is not sorted"
+for file in ${PACKAGES_FILES[@]}; do
+    # Replace / with - in the file path to avoid creating subdirs.
+    sorted_file="/tmp/sorted-${file/\//-}"
+
+    cat "${file}" | sort -u > "${sorted_file}"
+    if ! diff -u "${sorted_file}" "${file}"; then
+        echo "Lint error: ${file} is not sorted"
         exit 1
     fi
 done

Diff for: lint.sh

@@ -1,8 +1,5 @@
 # escape=`
-
-ARG BASE_IMAGE_VER=:1803
-
-FROM mcr.microsoft.com/windows/servercore${BASE_IMAGE_VER}
+FROM mcr.microsoft.com/windows/servercore:ltsc2019
 
 # Install the Visual C++ Build tools
 #