hack: base build scripts

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

hack/update-vendor

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+
+. $(dirname $0)/util
+set -eu -o pipefail -x
+
+: ${CONTINUOUS_INTEGRATION=}
+
+progressFlag=""
+if [ "$CONTINUOUS_INTEGRATION" == "true" ]; then progressFlag="--progress=plain"; fi
+
+case $buildmode in
+"buildkit")
+   output=$(mktemp -d -t buildctl-output.XXXXXXXXXX)
+  buildctl build $progressFlag --frontend=dockerfile.v0 --local context=. --local dockerfile=. \
+    --frontend-opt target=update \
+    --frontend-opt filename=./hack/dockerfiles/vendor.Dockerfile \
+    --output type=local,dest=$output
+  rm -rf ./vendor
+  cp -R "$output/out/" .
+  rm -rf $output
+  ;;
+*)
+  iidfile=$(mktemp -t docker-iidfile.XXXXXXXXXX)
+  case $buildmode in
+  "docker-buildkit")
+    export DOCKER_BUILDKIT=1
+    docker build --iidfile $iidfile -f ./hack/dockerfiles/vendor.Dockerfile --target update --force-rm .
+    ;;
+  *)
+		echo "buildctl or docker with buildkit support is required"
+	  exit 1
+    ;;
+  esac
+  iid=$(cat $iidfile)
+  cid=$(docker create $iid noop)
+  rm -rf ./vendor
+
+  docker cp $cid:/out/go.mod .
+  docker cp $cid:/out/go.sum .
+  docker cp $cid:/out/vendor .
+
+  docker rm $cid
+  rm -f $iidfile
+  ;;
+esac