Add SeaweedFS Alpine package build

scripts/apk/build.sh

@@ -0,0 +1,72 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+command_name="${1:-build}"
+requested_arch="${2:-${ALPINE_ARCH:-x86_64}}"
+repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+alpine_version="${ALPINE_VERSION:-3.22}"
+repo_name="${ALPINE_REPO_NAME:-local}"
+build_platform="${ALPINE_BUILD_PLATFORM:-linux/amd64}"
+
+validate_arch() {
+  case "$1" in
+    x86_64|aarch64) ;;
+    *) printf 'unsupported Alpine architecture: %s\n' "$1" >&2; return 2 ;;
+  esac
+}
+
+run_for_arch() {
+  local arch="$1"
+  local subcommand="$2"
+  local image_name
+
+  validate_arch "${arch}"
+  image_name="${ALPINE_APK_BUILDER_IMAGE:-seaweedfs-apk-builder:${arch}}"
+
+  docker build \
+    --platform "${build_platform}" \
+    --build-arg "ALPINE_VERSION=${alpine_version}" \
+    --build-arg "BUILDER_UID=$(id -u)" \
+    --build-arg "BUILDER_GID=$(id -g)" \
+    -f "${repo_root}/scripts/apk/Dockerfile" \
+    -t "${image_name}" \
+    "${repo_root}"
+
+  docker_args=(--rm --platform "${build_platform}")
+  if [[ -t 0 && -t 1 ]]; then
+    docker_args+=(-it)
+  fi
+
+  docker run "${docker_args[@]}" \
+    -e "ALPINE_ARCH=${arch}" \
+    -e "CARCH=${arch}" \
+    -e "ALPINE_REPO_NAME=${repo_name}" \
+    -e "PACKAGER=${PACKAGER:-Local Builder <local@example.invalid>}" \
+    -v "${repo_root}:/work" \
+    -v "${repo_root}/.cache/abuild:/home/builder/.abuild" \
+    -v "${repo_root}/.cache/apk-distfiles:/var/cache/distfiles" \
+    -v "${repo_root}/packages:/home/builder/packages" \
+    "${image_name}" \
+    "${subcommand}"
+}
+
+mkdir -p \
+  "${repo_root}/.cache/abuild" \
+  "${repo_root}/.cache/apk-distfiles" \
+  "${repo_root}/packages"
+
+case "${command_name}" in
+  build-all)
+    for arch in ${ALPINE_ARCHES:-x86_64 aarch64}; do
+      run_for_arch "${arch}" build
+    done
+    ;;
+  build|checksum|lint|shell)
+    run_for_arch "${requested_arch}" "${command_name}"
+    ;;
+  *)
+    printf 'unknown command: %s\n' "${command_name}" >&2
+    printf 'usage: %s [build|build-all|checksum|lint|shell] [x86_64|aarch64]\n' "$0" >&2
+    exit 2
+    ;;
+esac