Cache Unity Library for iOS TestFlight builds

.github/workflows/ios_testflight.yml

@@ -160,11 +160,18 @@ jobs:
       - name: Ensure Unity version installed
         run: ./ci/github_actions/ensure_unity_installed.sh ios
 
+      - name: Restore Unity Library cache
+        run: ./ci/github_actions/unity_library_cache.sh restore ios
+
       - name: Build iOS Unity Project
         id: build
         run: |
           ./ci/github_actions/build_unity_ios.sh "$EAGLE0_BUILD_DIR/eagle0iOS"
 
+      - name: Save Unity Library cache
+        if: success()
+        run: ./ci/github_actions/unity_library_cache.sh save ios
+
       - name: Upload Addressables to CDN
         if: success() && github.event.inputs.skip_upload != 'true'
         env:

ci/github_actions/unity_library_cache.sh

@@ -0,0 +1,105 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+COMMAND=${1:?Usage: unity_library_cache.sh restore|save <build-target>}
+BUILD_TARGET=${2:?Usage: unity_library_cache.sh restore|save <build-target>}
+
+PROJECT_DIR="src/main/csharp/net/eagle0/clients/unity/eagle0"
+LIBRARY_DIR="$PROJECT_DIR/Library"
+MARKER_FILE="$LIBRARY_DIR/.eagle0-library-cache-key"
+COMPLETE_FILE=".complete"
+
+CACHE_ROOT=${UNITY_LIBRARY_CACHE_RSYNC_URL:-rsync://lappy/unity-library-cache}
+
+UNITY_VERSION=$(grep "m_EditorVersion:" "$PROJECT_DIR/ProjectSettings/ProjectVersion.txt" | head -1 | sed 's/m_EditorVersion: //')
+PROJECT_HASH=$(
+    git ls-files -s -- \
+        "$PROJECT_DIR/Assets" \
+        "$PROJECT_DIR/Packages" \
+        "$PROJECT_DIR/ProjectSettings" \
+        | shasum -a 256 \
+        | awk '{print $1}'
+)
+CACHE_KEY="macos-${BUILD_TARGET}-${UNITY_VERSION}-${PROJECT_HASH}"
+CACHE_URL="${CACHE_ROOT%/}/${CACHE_KEY}"
+
+restore_cache() {
+    echo "Unity Library cache key: $CACHE_KEY"
+
+    if [ -d "$LIBRARY_DIR" ]; then
+        if [ ! -f "$MARKER_FILE" ]; then
+            echo "Existing Unity Library has no cache marker; removing it before restore."
+            rm -rf "$LIBRARY_DIR"
+        elif [ "$(cat "$MARKER_FILE")" != "$CACHE_KEY" ]; then
+            echo "Existing Unity Library cache key differs; removing it before restore."
+            echo "Existing: $(cat "$MARKER_FILE")"
+            echo "Current:  $CACHE_KEY"
+            rm -rf "$LIBRARY_DIR"
+        else
+            echo "Existing Unity Library already matches cache key."
+            return 0
+        fi
+    fi
+
+    local complete_marker
+    complete_marker=$(mktemp)
+    if ! rsync -q "${CACHE_URL}/${COMPLETE_FILE}" "$complete_marker"; then
+        echo "No complete Unity Library cache found at $CACHE_URL"
+        rm -f "$complete_marker"
+        return 0
+    fi
+    rm -f "$complete_marker"
+
+    echo "Restoring Unity Library from $CACHE_URL"
+    mkdir -p "$LIBRARY_DIR"
+    if ! rsync -a --delete "${CACHE_URL}/" "$LIBRARY_DIR/"; then
+        echo "Unity Library cache restore failed; removing partial restore."
+        rm -rf "$LIBRARY_DIR"
+        return 0
+    fi
+
+    printf '%s\n' "$CACHE_KEY" > "$MARKER_FILE"
+    echo "Unity Library cache restore complete."
+}
+
+save_cache() {
+    if [ ! -d "$LIBRARY_DIR" ]; then
+        echo "Unity Library does not exist; nothing to cache."
+        return 0
+    fi
+
+    echo "Saving Unity Library cache to $CACHE_URL"
+    printf '%s\n' "$CACHE_KEY" > "$MARKER_FILE"
+    rm -f "$LIBRARY_DIR/$COMPLETE_FILE"
+
+    if ! rsync -a --delete "$LIBRARY_DIR/" "${CACHE_URL}/"; then
+        echo "WARNING: Unity Library cache save failed."
+        return 0
+    fi
+
+    local complete_marker
+    complete_marker=$(mktemp)
+    printf '%s\n' "$CACHE_KEY" > "$complete_marker"
+    if ! rsync -q "$complete_marker" "${CACHE_URL}/${COMPLETE_FILE}"; then
+        echo "WARNING: Unity Library cache completion marker upload failed."
+        rm -f "$complete_marker"
+        return 0
+    fi
+    rm -f "$complete_marker"
+
+    echo "Unity Library cache save complete."
+}
+
+case "$COMMAND" in
+    restore)
+        restore_cache
+        ;;
+    save)
+        save_cache
+        ;;
+    *)
+        echo "Usage: unity_library_cache.sh restore|save <build-target>"
+        exit 2
+        ;;
+esac