build: add script to build images with buildah

.gitignore

@@ -284,3 +284,4 @@ local.properties
 
 ./rc-*
 rc-simulator
+rc-simulator.*

build-docker.sh

@@ -0,0 +1,49 @@
+#! /bin/bash
+
+IMAGE_NAME=robocar-simulator
+TAG=$(git describe)
+FULL_IMAGE_NAME=docker.io/cyrilix/${IMAGE_NAME}:${TAG}
+BINARY=rc-simulator
+
+GOTAGS="-tags netgo"
+
+image_build(){
+  local platform=$1
+
+
+  GOOS=$(echo $platform | cut -f1 -d/) && \
+  GOARCH=$(echo $platform | cut -f2 -d/) && \
+  GOARM=$(echo $platform | cut -f3 -d/ | sed "s/v//" )
+  VARIANT="--variant $(echo $platform | cut -f3 -d/  )"
+  if [[ -z "$GOARM" ]] ;
+  then
+  VARIANT=""
+  fi
+
+  local binary_suffix="$GOARCH$(echo $platform | cut -f3 -d/ )"
+
+  local containerName="$IMAGE_NAME-$GOARCH$GOARM"
+
+
+  printf "\n\nBuild go binary %s\n\n" "${BINARY}.${binary_suffix}"
+  CGO_ENABLED=0 GOOS=${GOOS} GOARCH=${GOARCH} GOARM=${GOARM} go build -mod vendor -a ${GOTAGS} -o "${BINARY}.${binary_suffix}" ./cmd/${BINARY}/
+
+  buildah --os "$GOOS" --arch "$GOARCH" $VARIANT  --name "$containerName" from gcr.io/distroless/static
+  buildah config --user 1234 "$containerName"
+  buildah copy "$containerName" "${BINARY}.${binary_suffix}" /go/bin/$BINARY
+  buildah config --entrypoint '["/go/bin/'$BINARY'"]' "${containerName}"
+
+  buildah commit --rm --manifest $IMAGE_NAME "${containerName}" "${containerName}"
+}
+
+buildah rmi localhost/$IMAGE_NAME
+buildah manifest rm localhost/${IMAGE_NAME}
+
+image_build linux/amd64
+image_build linux/arm64
+image_build linux/arm/v7
+
+
+# push image
+printf "\n\nPush manifest to %s\n\n" ${FULL_IMAGE_NAME}
+buildah manifest push --rm -f v2s2 "localhost/$IMAGE_NAME" "docker://$FULL_IMAGE_NAME" --all