Add script to generate cross-platform Dockerfile.

Author: felddy

buildx-dockerfile.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+# Create a Dockerfile suitable for a multi-platform build using buildx
+# See: https://docs.docker.com/buildx/working-with-buildx/
+
+set -o nounset
+set -o errexit
+set -o pipefail
+
+DOCKERFILE=Dockerfile
+DOCKERFILEX=Dockerfile-x
+
+# We don't want this expression to expand.
+# shellcheck disable=SC2016
+sed 's/^FROM /FROM --platform=$TARGETPLATFORM /g' < $DOCKERFILE > $DOCKERFILEX