Cache Rust build artifacts for Alpine packages

scripts/apk/Dockerfile

@@ -18,9 +18,15 @@ RUN addgroup -g "${BUILDER_GID}" builder \
   && adduser -D -u "${BUILDER_UID}" -G builder builder \
   && addgroup builder abuild \
   && addgroup builder wheel \
-  && mkdir -p /var/cache/distfiles /home/builder/packages \
+  && mkdir -p \
+    /var/cache/distfiles \
+    /home/builder/.cache/cargo \
+    /home/builder/.cache/cargo-target \
+    /home/builder/.cache/rustup \
+    /home/builder/packages \
   && chgrp abuild /var/cache/distfiles /home/builder/packages \
   && chmod g+w /var/cache/distfiles /home/builder/packages \
+  && chown -R builder:builder /home/builder/.cache \
   && printf 'permit nopass :wheel\n' > /etc/doas.d/wheel.conf \
   && printf '%%wheel ALL=(ALL) NOPASSWD: ALL\n' > /etc/sudoers.d/wheel
 

scripts/apk/build.sh

@@ -19,6 +19,39 @@ if [[ "${builder_gid}" == "0" ]]; then
   builder_gid=1000
 fi
 
+cache_scope_from_remote() {
+  local remote
+  local path
+  local owner
+  local repo
+
+  remote="$(git -C "${repo_root}" remote get-url origin 2>/dev/null || true)"
+  remote="${remote%.git}"
+
+  case "${remote}" in
+    ssh://*/*/*)
+      path="${remote#ssh://*/}"
+      ;;
+    http://*/*/*|https://*/*/*)
+      path="${remote#*://*/}"
+      ;;
+    *:*)
+      path="${remote#*:}"
+      ;;
+    *)
+      path="$(basename "${repo_root}")"
+      ;;
+  esac
+
+  owner="$(basename "$(dirname "${path}")")"
+  repo="$(basename "${path}")"
+  if [[ -n "${owner}" && "${owner}" != "." && -n "${repo}" ]]; then
+    printf '%s-%s\n' "${owner}" "${repo}" | sed 's/[^A-Za-z0-9_.-]/-/g'
+  else
+    printf '%s\n' "$(basename "${repo_root}")" | sed 's/[^A-Za-z0-9_.-]/-/g'
+  fi
+}
+
 validate_arch() {
   case "$1" in
     x86_64|aarch64) ;;
@@ -32,11 +65,17 @@ run_for_arch() {
   local package_dir="$3"
   local image_name
   local container_package_dir
+  local package_name
+  local cache_scope
+  local cache_prefix
 
   validate_arch "${arch}"
   apk_validate_package_dir "${package_dir}"
+  package_name="$(apk_package_name "${package_dir}")"
   container_package_dir="$(apk_container_package_dir "${repo_root}" "${package_dir}")"
   image_name="${ALPINE_APK_BUILDER_IMAGE:-alpine-apk-builder:${arch}}"
+  cache_scope="${ALPINE_APK_CACHE_SCOPE:-$(cache_scope_from_remote)}"
+  cache_prefix="${ALPINE_APK_CACHE_PREFIX:-alpine-apk}-${cache_scope}-${package_name}-${arch}"
 
   docker build \
     --platform "${build_platform}" \
@@ -57,7 +96,13 @@ run_for_arch() {
     -e "CARCH=${arch}" \
     -e "ALPINE_REPO_NAME=${repo_name}" \
     -e "APKBUILD_DIR=${container_package_dir}" \
+    -e "CARGO_HOME=/home/builder/.cache/cargo" \
+    -e "CARGO_TARGET_DIR=/home/builder/.cache/cargo-target" \
     -e "PACKAGER=${PACKAGER:-Joachim Schlöffel <me@joachim-schloeffel.com>}" \
+    -e "RUSTUP_HOME=/home/builder/.cache/rustup" \
+    -v "${cache_prefix}-cargo:/home/builder/.cache/cargo" \
+    -v "${cache_prefix}-cargo-target:/home/builder/.cache/cargo-target" \
+    -v "${cache_prefix}-rustup:/home/builder/.cache/rustup" \
     -v "${repo_root}:/work" \
     -v "${repo_root}/.cache/abuild:/home/builder/.abuild" \
     -v "${repo_root}/.cache/apk-distfiles:/var/cache/distfiles" \