test-build: port dep cache, namespaced by image digest

2 files changed, 112 insertions, 0 deletions

diff --git a/.extras/test-build b/.extras/test-build
index a7e796e..1f7920c 100755
--- a/.extras/test-build
+++ b/.extras/test-build
@@ -286,6 +286,92 @@ apply_overrides_to_order() {
   RESOLVED_ORDER=("${keep[@]:-}")
 }
 
+# =============================================================================
+# Dependency cache. Layout: $CACHE_ROOT/<cat>/<prog>/<prog>-<ver>-...txz where
+# CACHE_ROOT = $PKG_CACHE/<image-digest> (set per run by resolve_cache_root).
+# Key is prog+version. --no-cache (USE_CACHE=0) or empty PKG_CACHE disables.
+# =============================================================================
+CACHE_ROOT=""   # set by resolve_cache_root once the image digest is known
+
+# True when the cache is usable this run.
+_cache_on() { [[ $USE_CACHE -eq 1 && -n "$PKG_CACHE" && -n "$CACHE_ROOT" ]]; }
+
+_cache_ver_of() {
+  local prog="$1" base="$2"
+  base="${base#"$prog"-}"
+  echo "${base%%-*}"
+}
+
+# cache_decision <cat> <prog> <version> -> cached | bump:OLD:NEW | new
+cache_decision() {
+  local cat="$1" prog="$2" version="$3"
+  _cache_on || { echo new; return; }
+  local dir="$CACHE_ROOT/$cat/$prog"
+  local f newest=""
+  for f in "$dir/$prog"-*.t?z; do
+    [[ -e "$f" ]] || continue
+    [[ -z "$newest" || "$f" -nt "$newest" ]] && newest="$f"
+  done
+  [[ -z "$newest" ]] && { echo new; return; }
+  local have; have="$(_cache_ver_of "$prog" "$(basename "$newest")")"
+  if [[ "$have" == "$version" ]]; then echo cached; else echo "bump:$have:$version"; fi
+}
+
+cache_path() {
+  local cat="$1" prog="$2" version="$3"
+  _cache_on || return
+  local dir="$CACHE_ROOT/$cat/$prog"
+  local f newest=""
+  for f in "$dir/$prog"-*.t?z; do
+    [[ -e "$f" ]] || continue
+    [[ -z "$newest" || "$f" -nt "$newest" ]] && newest="$f"
+  done
+  [[ -z "$newest" ]] && return
+  [[ "$(_cache_ver_of "$prog" "$(basename "$newest")")" == "$version" ]] && echo "$newest"
+}
+
+cache_store() {
+  local cat="$1" prog="$2" src="$3"
+  _cache_on || return
+  local dir="$CACHE_ROOT/$cat/$prog"
+  mkdir -p "$dir"
+  rm -f "$dir"/*.t?z
+  cp -a "$src" "$dir/"
+}
+
+cache_label() {
+  local dir="$1" is_target="$2"
+  local cat prog ver dec
+  cat="$(category_of "$dir")"; prog="$(basename "$dir")"; ver="$(version_of "$dir")"
+  dec="$(cache_decision "$cat" "$prog" "$ver")"
+  local label
+  case "$dec" in
+    cached)   label="cached ($ver)" ;;
+    bump:*)   label="rebuild: ${dec#bump:}"; label="${label/:/ -> }" ;;
+    *)        label="build (new)" ;;
+  esac
+  if [[ "$is_target" == "1" ]]; then
+    case "$dec" in
+      cached) label="build (cached $ver, rebuilt as target)" ;;
+    esac
+    echo "target, $label"
+  else
+    echo "$label"
+  fi
+}
+
+# Compute CACHE_ROOT from the image's digest. Falls back to the tag if the
+# digest cannot be read (still isolates per image reference).
+resolve_cache_root() {
+  [[ -z "$PKG_CACHE" ]] && { CACHE_ROOT=""; return; }
+  local digest
+  digest="$(docker image inspect --format '{{index .Id}}' "$ACTIVE_IMAGE" 2>/dev/null)"
+  [[ -z "$digest" ]] && digest="tag-${ACTIVE_IMAGE//[^a-zA-Z0-9._-]/_}"
+  digest="${digest//[^a-zA-Z0-9._-]/_}"
+  CACHE_ROOT="$PKG_CACHE/$digest"
+  mkdir -p "$CACHE_ROOT"
+}
+
 main() {
   parse_args "$@"
   init_color
diff --git a/.extras/test-logic.sh b/.extras/test-logic.sh
index e48586e..d4249bb 100644
--- a/.extras/test-logic.sh
+++ b/.extras/test-logic.sh
@@ -107,6 +107,32 @@ load_overrides
 [[ ${#OV_DROP[@]} -eq 0 ]] && ok "overrides inert on 15.0" || bad "overrides applied on 15.0"
 VERSION_ID="current"
 
+# --- cache ------------------------------------------------------------------
+PKG_CACHE=$(mktemp -d)
+CACHE_ROOT="$PKG_CACHE/sha256-deadbeef"   # simulate a resolved digest namespace
+mkc() { mkdir -p "$CACHE_ROOT/$1/$2"; : > "$CACHE_ROOT/$1/$2/$3"; }
+
+mkc net libfoo "libfoo-1.1-x86_64-1_danix.txz"
+[[ "$(cache_decision net libfoo 1.1)" == "cached" ]] && ok "cache hit on version match" || bad "cache_decision got [$(cache_decision net libfoo 1.1)]"
+[[ "$(cache_decision net libfoo 1.2)" == "bump:1.1:1.2" ]] && ok "cache bump reported" || bad "cache bump got [$(cache_decision net libfoo 1.2)]"
+[[ "$(cache_decision net libbar 1.0)" == "new" ]] && ok "cache new for absent" || bad "cache new got [$(cache_decision net libbar 1.0)]"
+
+hit="$(cache_path net libfoo 1.1)"
+[[ "$hit" == "$CACHE_ROOT/net/libfoo/libfoo-1.1-x86_64-1_danix.txz" ]] && ok "cache_path returns hit" || bad "cache_path got [$hit]"
+[[ -z "$(cache_path net libfoo 9.9)" ]] && ok "cache_path empty on miss" || bad "cache_path not empty on miss"
+
+srctmp=$(mktemp -d); : > "$srctmp/libfoo-1.2-x86_64-1_danix.txz"
+cache_store net libfoo "$srctmp/libfoo-1.2-x86_64-1_danix.txz"
+count=$(find "$CACHE_ROOT/net/libfoo" -name '*.t?z' | wc -l)
+[[ "$count" -eq 1 ]] && ok "cache_store evicts to one file" || bad "cache_store left $count files"
+[[ -e "$CACHE_ROOT/net/libfoo/libfoo-1.2-x86_64-1_danix.txz" ]] && ok "cache_store stored new file" || bad "cache_store did not store"
+rm -rf "$srctmp"
+
+# disabled cache -> new
+CACHE_ROOT_SAVE="$CACHE_ROOT"; USE_CACHE=0
+[[ "$(cache_decision net libfoo 1.2)" == "new" ]] && ok "--no-cache disables (new)" || bad "disabled cache got [$(cache_decision net libfoo 1.2)]"
+USE_CACHE=1; CACHE_ROOT="$CACHE_ROOT_SAVE"
+
 echo
 echo "$pass passed, $fail failed"
 [[ $fail -eq 0 ]] || exit 1