feat: add multiarch mikrotik builds

vendorbuild/mikrotik/build.sh

@@ -1,11 +1,22 @@
 #!/bin/bash
 
 set -e
-
 version=$(git describe --tags "$(git rev-list --tags --max-count=1)" | cut -c2-)
 
-# The docker build command is run in the directory at the root of the project, meaning the Dockerfile needs to reference files according to relative paths
-docker build --output type=tar,dest=pathvector-"$version"-mikrotik-amd64.tar -t pathvector-cron:"$version"-amd64 -f ../vendorbuild/mikrotik/Dockerfile ..
+# Download docker-buildx if it doesn't already exist
+docker_buildx="../vendorbuild/mikrotik/docker-buildx"
+if [ ! -d "$docker_buildx" ]; then
+  curl -L https://github.com/docker/buildx/releases/download/v0.6.3/buildx-v0.6.3.linux-amd64 -o $docker_buildx
+  chmod +x $docker_buildx
+fi
 
-# This isn't needed on my machine but it is on GitHub Actions. Not high priority to fix at the moment.
-docker save pathvector-cron:"$version"-amd64 > pathvector-"$version"-mikrotik-amd64.tar
+for arch in amd64 arm64v8; do
+  echo "Building for $arch..."
+  # The build command is run in the directory at the root of the project, so the Dockerfile needs to reference files according to relative paths
+  $docker_buildx build \
+    --output type=tar,dest=pathvector-$version-mikrotik-$arch.tar \
+    -t pathvector-mikrotik:$version-$arch \
+    --build-arg ARCH=$arch \
+    -f ../vendorbuild/mikrotik/Dockerfile \
+    ..
+done