From f879b6ac039467689c2acc8b42ec3e154c73a51f Mon Sep 17 00:00:00 2001
From: Eric Promislow <epromislow@suse.com>
Date: Wed, 28 Feb 2024 09:37:25 -0800
Subject: [PATCH] Bring the 3.0 CROSS_ARCH changes into v4.0

---
 DEVELOPING.md     |  5 ++++-
 Dockerfile.dapper |  2 +-
 scripts/build     | 29 +++++++++++++++++++++++++----
 scripts/package   |  6 +++++-
 4 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/DEVELOPING.md b/DEVELOPING.md
index f6c9a053..81d2db7f 100644
--- a/DEVELOPING.md
+++ b/DEVELOPING.md
@@ -63,7 +63,10 @@ If you want to interact with the Minio deployed in the cluster, you can use the
 
 ### Building on Different Architectures
 
-Currently we only support building this chart for amd64 nodes. The binary built by `make build` is set to build for amd64 and we have also included a flag for users running different architectures when trying to package the code into a docker image. Setting `USE_DOCKER_BUILDX=1` will force the package script to use docker buildx, setting the target platform to build for amd64. If you do not have `docker-buildx` installed please reference [this page](https://docs.docker.com/buildx/working-with-buildx/).
+Currently, we only support building this chart fully for `amd64` nodes. The binary and image building scripts will build "arch native" by default.
+So when building on `amd64` the resulting binary and image will both be `amd64` - same for `arm64`. This is how the drone builds operate.
+
+We have also included a flag for users running different architectures when trying to package the code into an `amd64` docker image. Building the binary with `CROSS_ARCH=true` set will cause it to build `amd64` and `arm64` binaries, and then setting `USE_DOCKER_BUILDX=1` will force the package script to use docker buildx, setting the container's target platform to build for `amd64`. If you do not have `docker-buildx` installed please reference [this page](https://docs.docker.com/buildx/working-with-buildx/).
 
 
 ### Developer Uninstallation
diff --git a/Dockerfile.dapper b/Dockerfile.dapper
index ff67a9f4..8e950c0d 100644
--- a/Dockerfile.dapper
+++ b/Dockerfile.dapper
@@ -37,7 +37,7 @@ RUN if [ "${ARCH}" != "s390x" ]; then \
         chmod +x /usr/local/bin/mc; \
     fi
 
-ENV DAPPER_ENV REPO TAG DRONE_TAG CROSS USE_DOCKER_BUILDX
+ENV DAPPER_ENV REPO TAG DRONE_TAG CROSS CROSS_ARCH USE_DOCKER_BUILDX
 ENV DAPPER_SOURCE /go/src/github.com/rancher/backup-restore-operator/
 ENV DAPPER_OUTPUT ./bin ./dist
 ENV GOCACHE /root/.cache/go-build
diff --git a/scripts/build b/scripts/build
index bdd7f84c..c78fbd16 100755
--- a/scripts/build
+++ b/scripts/build
@@ -11,8 +11,29 @@ if [ "$(uname)" = "Linux" ]; then
 fi
 LINKFLAGS="-X main.Version=$VERSION"
 LINKFLAGS="-X main.GitCommit=$COMMIT $LINKFLAGS"
-CGO_ENABLED=0 go build -ldflags "$LINKFLAGS $OTHER_LINKFLAGS" -o bin/backup-restore-operator
-if [ "$CROSS" = "true" ] && [ "$ARCH" = "amd64" ]; then
-    GOOS=darwin go build -ldflags "$LINKFLAGS" -o bin/backup-restore-operator-darwin
-    GOOS=windows go build -ldflags "$LINKFLAGS" -o bin/backup-restore-operator-windows
+
+
+ARCHES=( "$ARCH" )
+# Set CROSS_ARCH to build for the other architecture
+if [ "$CROSS_ARCH" == "true" ]; then
+  case "$ARCH" in
+    amd64) XARCH=arm64 ;;
+    arm64) XARCH=amd64 ;;
+    *) echo "Unsupported ARCH of $ARCH" 1>&2 ; exit 1
+  esac
+  ARCHES+=( "$XARCH" )
 fi
+
+for A in "${ARCHES[@]}" ; do
+  GOARCH="$A" CGO_ENABLED=0 go build -ldflags "$LINKFLAGS $OTHER_LINKFLAGS" -o "bin/backup-restore-operator-$A"
+  # Set CROSS to build for other OS'es
+  if [ "$CROSS" = "true" ]; then
+    for OS in darwin windows ; do
+          GOARCH="$A" GOOS=$OS go build -ldflags "$LINKFLAGS" -o "bin/backup-restore-operator-$OS-$A"
+    done
+  fi
+done
+
+cd bin
+ln -sf "./backup-restore-operator-$ARCH" "./backup-restore-operator"
+cd ..
diff --git a/scripts/package b/scripts/package
index dfd35339..e0a4b80f 100755
--- a/scripts/package
+++ b/scripts/package
@@ -6,7 +6,11 @@ source $(dirname $0)/version
 cd $(dirname $0)/..
 
 mkdir -p dist/artifacts
-cp bin/backup-restore-operator dist/artifacts/backup-restore-operator${SUFFIX}
+if [ "$CROSS_ARCH" != "true" ]; then
+  cp bin/backup-restore-operator dist/artifacts/backup-restore-operator${SUFFIX}
+else
+  cp bin/backup-restore-operator${SUFFIX} dist/artifacts/
+fi
 
 IMAGE=${REPO}/backup-restore-operator:${TAG}
 DOCKERFILE=package/Dockerfile