Set BASHBREW_BUILDKIT_SYNTAX and respect "Builder:" in GitHub Actions…

… scripts

scripts/github-actions/generate.sh

@@ -55,6 +55,7 @@ for tag in $tags; do
  "tags": {{- json ($.Tags namespace false $e) -}},
  "directory": {{- json ($e.ArchDirectory $arch) -}},
  "file": {{- json ($e.ArchFile $arch) -}},
+ "builder": {{- json ($e.ArchBuilder $arch) -}}
  "constraints": {{- json $e.Constraints -}},
  "froms": {{- json ($.ArchDockerFroms $arch $e) -}}
  {{- "}" -}}
@@ -77,7 +78,14 @@ for tag in $tags; do
  runs: {
  build: (
  [
- "docker build"
+ # https://github.com/docker-library/bashbrew/pull/43
+ if .builder == "classic" or .builder == "" then
+ "DOCKER_BUILDKIT=0 docker build"
+ elif .builder == "buildkit" then
+ "docker buildx build --progress plain --build-arg BUILDKIT_SYNTAX=\"$BASHBREW_BUILDKIT_SYNTAX\"
+ else
+ "echo >&2 " + ("error: unknown/unsupported builder: " + .builder | @sh) + "\nexit 1\n#"
+ end
  ]
  + (
  .tags
@@ -165,6 +173,10 @@ strategy="$(
  end
  ),
  "git clone --depth 1 https://github.com/docker-library/official-images.git -b master ~/oi",
+
+ # https://github.com/docker-library/bashbrew/pull/43
+ "echo BASHBREW_BUILDKIT_SYNTAX=\"$(< ~/oi/.bashbrew-buildkit-syntax)\" >> \"$GITHUB_ENV\"",
+
  "# create a dummy empty image/layer so we can --filter since= later to get a meaningful image list",
  "{ echo FROM " + (
  if .os | startswith("windows-") then