fix: stop uploading empty placeholder cache tars to S3

The build workflow created empty tar files (via `tar --files-from /dev/null`)
as placeholders before remote-cli-post-build runs. When the container is
OOM-killed, only these ~10KB empty tars survive and get uploaded to S3.
On the next build, the pull-cache hook downloads them and extracts an empty
Library, providing zero caching benefit.

Changes:
- Remove empty placeholder tar creation in build-automation-workflow.ts
- Keep mkdir -p for cache directories (hooks need them)
- Add size check in aws-s3-upload-cache hook to delete tar files < 1KB
  before uploading, as a safety net against stale stubs

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/build-tests-windows.yml

@@ -39,7 +39,7 @@ jobs:
           - unityVersion: 6000.0.36f1
             targetPlatform: StandaloneWindows64
             buildProfile: 'Assets/Settings/Build Profiles/Sample Windows Build Profile.asset'
-
+  
     steps:
       ###########################
       #         Checkout        #
@@ -66,34 +66,6 @@ jobs:
         run: |
           Move-Item -Path "./test-project/ProjectSettings/ProjectSettingsIl2cpp.asset" -Destination "./test-project/ProjectSettings/ProjectSettings.asset" -Force
 
-      ###########################
-      #    Docker Readiness     #
-      ###########################
-      - name: Ensure Docker daemon is ready
-        timeout-minutes: 2
-        shell: powershell
-        run: |
-          $maxRetries = 10
-          $retryDelay = 6
-          for ($i = 0; $i -lt $maxRetries; $i++) {
-            $svc = Get-Service docker -ErrorAction SilentlyContinue
-            if ($svc -and $svc.Status -eq 'Running') {
-              docker version 2>$null
-              if ($LASTEXITCODE -eq 0) {
-                Write-Host "Docker is ready."
-                exit 0
-              }
-            }
-            if ($svc -and $svc.Status -eq 'Stopped') {
-              Write-Host "Docker service stopped, attempting to start..."
-              Start-Service docker -ErrorAction SilentlyContinue
-            }
-            Write-Host "Waiting for Docker daemon (attempt $($i+1)/$maxRetries)..."
-            Start-Sleep -Seconds $retryDelay
-          }
-          Write-Error "Docker daemon did not start within $($maxRetries * $retryDelay) seconds"
-          exit 1
-
       ###########################
       #          Build          #
       ###########################
@@ -174,8 +146,6 @@ jobs:
       ###########################
       - uses: actions/upload-artifact@v4
         with:
-          name:
-            Build ${{ matrix.targetPlatform }} on Windows (${{ matrix.unityVersion }})${{ matrix.enableGpu && ' With
-            GPU' || '' }}${{ matrix.buildProfile && '  With Build Profile' || '' }}
+          name: Build ${{ matrix.targetPlatform }} on Windows (${{ matrix.unityVersion }})${{ matrix.enableGpu && ' With GPU' || '' }}${{ matrix.buildProfile && '  With Build Profile' || '' }}
           path: build
           retention-days: 14

.github/workflows/sync-secrets.yml

@@ -1,81 +0,0 @@
-name: Sync Secrets to Repositories
-
-on:
-  workflow_dispatch:
-    inputs:
-      target_repo:
-        description: 'Target repository (org/repo format)'
-        required: true
-        default: 'game-ci/orchestrator'
-        type: choice
-        options:
-          - game-ci/orchestrator
-          - game-ci/cli
-      dry_run:
-        description: 'Dry run (list secrets to sync without writing)'
-        required: false
-        default: false
-        type: boolean
-
-jobs:
-  sync-secrets:
-    name: Sync secrets to ${{ inputs.target_repo }}
-    runs-on: ubuntu-latest
-    steps:
-      - name: Sync secrets
-        env:
-          GH_TOKEN: ${{ secrets.GIT_PRIVATE_TOKEN }}
-          TARGET_REPO: ${{ inputs.target_repo }}
-          DRY_RUN: ${{ inputs.dry_run }}
-          # Secrets to sync — values come from repo + org secrets available here
-          SECRET_UNITY_EMAIL: ${{ secrets.UNITY_EMAIL }}
-          SECRET_UNITY_PASSWORD: ${{ secrets.UNITY_PASSWORD }}
-          SECRET_UNITY_SERIAL: ${{ secrets.UNITY_SERIAL }}
-          SECRET_GIT_PRIVATE_TOKEN: ${{ secrets.GIT_PRIVATE_TOKEN }}
-          SECRET_LOCALSTACK_AUTH_TOKEN: ${{ secrets.LOCALSTACK_AUTH_TOKEN }}
-          SECRET_GOOGLE_SERVICE_ACCOUNT_EMAIL: ${{ secrets.GOOGLE_SERVICE_ACCOUNT_EMAIL }}
-          SECRET_GOOGLE_SERVICE_ACCOUNT_KEY: ${{ secrets.GOOGLE_SERVICE_ACCOUNT_KEY }}
-          SECRET_CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
-        run: |
-          SECRETS=(
-            "UNITY_EMAIL:SECRET_UNITY_EMAIL"
-            "UNITY_PASSWORD:SECRET_UNITY_PASSWORD"
-            "UNITY_SERIAL:SECRET_UNITY_SERIAL"
-            "GIT_PRIVATE_TOKEN:SECRET_GIT_PRIVATE_TOKEN"
-            "LOCALSTACK_AUTH_TOKEN:SECRET_LOCALSTACK_AUTH_TOKEN"
-            "GOOGLE_SERVICE_ACCOUNT_EMAIL:SECRET_GOOGLE_SERVICE_ACCOUNT_EMAIL"
-            "GOOGLE_SERVICE_ACCOUNT_KEY:SECRET_GOOGLE_SERVICE_ACCOUNT_KEY"
-            "CODECOV_TOKEN:SECRET_CODECOV_TOKEN"
-          )
-
-          synced=0
-          skipped=0
-
-          for entry in "${SECRETS[@]}"; do
-            name="${entry%%:*}"
-            env_var="${entry##*:}"
-            value="${!env_var}"
-
-            if [ -z "$value" ]; then
-              echo "⏭ SKIP: $name (not available in this repo's context)"
-              skipped=$((skipped + 1))
-              continue
-            fi
-
-            if [ "$DRY_RUN" = "true" ]; then
-              echo "🔍 DRY RUN: would sync $name → $TARGET_REPO"
-            else
-              echo "$value" | gh secret set "$name" -R "$TARGET_REPO" --body -
-              echo "✅ SYNCED: $name → $TARGET_REPO"
-            fi
-            synced=$((synced + 1))
-          done
-
-          echo ""
-          echo "=== Summary ==="
-          echo "Synced: $synced"
-          echo "Skipped (not available): $skipped"
-          echo "Target: $TARGET_REPO"
-          if [ "$DRY_RUN" = "true" ]; then
-            echo "Mode: DRY RUN (no secrets were written)"
-          fi

dist/index.js

@@ -9419,6 +9419,10 @@ class ContainerHookService {
       fi
       ENDPOINT_ARGS=""
       if [ -n "$AWS_S3_ENDPOINT" ]; then ENDPOINT_ARGS="--endpoint-url $AWS_S3_ENDPOINT"; fi
+      # Skip uploading empty or near-empty tar files (< 1KB) — these are leftover
+      # stubs with no real cache data and would poison the cache for the next build.
+      find /data/cache/$CACHE_KEY/lfs -name "*.tar*" -size -1k -delete 2>/dev/null || true
+      find /data/cache/$CACHE_KEY/Library -name "*.tar*" -size -1k -delete 2>/dev/null || true
       aws $ENDPOINT_ARGS s3 cp --recursive /data/cache/$CACHE_KEY/lfs s3://${orchestrator_1.default.buildParameters.awsStackName}/orchestrator-cache/$CACHE_KEY/lfs || true
       rm -r /data/cache/$CACHE_KEY/lfs || true
       aws $ENDPOINT_ARGS s3 cp --recursive /data/cache/$CACHE_KEY/Library s3://${orchestrator_1.default.buildParameters.awsStackName}/orchestrator-cache/$CACHE_KEY/Library || true
@@ -9912,13 +9916,14 @@ echo "CACHE_KEY=$CACHE_KEY"`;
     if ! command -v yarn > /dev/null 2>&1; then printf '#!/bin/sh\nexit 0\n' > /usr/local/bin/yarn && chmod +x /usr/local/bin/yarn; fi
     # Pipe entrypoint.sh output through log stream to capture Unity build output (including "Build succeeded")
     { echo "game ci start"; echo "game ci start" >> /home/job-log.txt; echo "CACHE_KEY=$CACHE_KEY"; echo "$CACHE_KEY"; if [ -n "$LOCKED_WORKSPACE" ]; then echo "Retained Workspace: true"; fi; if [ -n "$LOCKED_WORKSPACE" ] && [ -d "$GITHUB_WORKSPACE/.git" ]; then echo "Retained Workspace Already Exists!"; fi; /entrypoint.sh; } | node ${builderPath} -m remote-cli-log-stream --logFile /home/job-log.txt
+    # Ensure cache directories exist for post-build and S3 upload hooks.
+    # Do NOT create empty placeholder tars — they waste S3 storage and on next
+    # build the pull-cache hook downloads them, giving Unity an empty Library
+    # (no caching benefit). The real tars are created by remote-cli-post-build
+    # via Caching.PushToCache(), and the S3 upload hooks use || true so missing
+    # files are handled gracefully.
     mkdir -p "/data/cache/$CACHE_KEY/Library"
-    if [ ! -f "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar" ] && [ ! -f "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar.lz4" ]; then
-      tar -cf "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar" --files-from /dev/null || touch "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar"
-    fi
-    if [ ! -f "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar" ] && [ ! -f "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar.lz4" ]; then
-      tar -cf "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar" --files-from /dev/null || touch "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar"
-    fi
+    mkdir -p "/data/cache/$CACHE_KEY/build"
     # Run post-build tasks and capture output
     # Note: Post-build may clean up the builder directory, so we write output directly to log file
     # Use set +e to allow the command to fail without exiting the script

src/model/orchestrator/services/hooks/container-hook-service.ts

@@ -155,6 +155,10 @@ export class ContainerHookService {
       fi
       ENDPOINT_ARGS=""
       if [ -n "$AWS_S3_ENDPOINT" ]; then ENDPOINT_ARGS="--endpoint-url $AWS_S3_ENDPOINT"; fi
+      # Skip uploading empty or near-empty tar files (< 1KB) — these are leftover
+      # stubs with no real cache data and would poison the cache for the next build.
+      find /data/cache/$CACHE_KEY/lfs -name "*.tar*" -size -1k -delete 2>/dev/null || true
+      find /data/cache/$CACHE_KEY/Library -name "*.tar*" -size -1k -delete 2>/dev/null || true
       aws $ENDPOINT_ARGS s3 cp --recursive /data/cache/$CACHE_KEY/lfs s3://${
         Orchestrator.buildParameters.awsStackName
       }/orchestrator-cache/$CACHE_KEY/lfs || true

src/model/orchestrator/workflows/build-automation-workflow.ts

@@ -170,13 +170,14 @@ echo "CACHE_KEY=$CACHE_KEY"`;
     if ! command -v yarn > /dev/null 2>&1; then printf '#!/bin/sh\nexit 0\n' > /usr/local/bin/yarn && chmod +x /usr/local/bin/yarn; fi
     # Pipe entrypoint.sh output through log stream to capture Unity build output (including "Build succeeded")
     { echo "game ci start"; echo "game ci start" >> /home/job-log.txt; echo "CACHE_KEY=$CACHE_KEY"; echo "$CACHE_KEY"; if [ -n "$LOCKED_WORKSPACE" ]; then echo "Retained Workspace: true"; fi; if [ -n "$LOCKED_WORKSPACE" ] && [ -d "$GITHUB_WORKSPACE/.git" ]; then echo "Retained Workspace Already Exists!"; fi; /entrypoint.sh; } | node ${builderPath} -m remote-cli-log-stream --logFile /home/job-log.txt
+    # Ensure cache directories exist for post-build and S3 upload hooks.
+    # Do NOT create empty placeholder tars — they waste S3 storage and on next
+    # build the pull-cache hook downloads them, giving Unity an empty Library
+    # (no caching benefit). The real tars are created by remote-cli-post-build
+    # via Caching.PushToCache(), and the S3 upload hooks use || true so missing
+    # files are handled gracefully.
     mkdir -p "/data/cache/$CACHE_KEY/Library"
-    if [ ! -f "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar" ] && [ ! -f "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar.lz4" ]; then
-      tar -cf "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar" --files-from /dev/null || touch "/data/cache/$CACHE_KEY/Library/lib-$BUILD_GUID.tar"
-    fi
-    if [ ! -f "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar" ] && [ ! -f "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar.lz4" ]; then
-      tar -cf "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar" --files-from /dev/null || touch "/data/cache/$CACHE_KEY/build/build-$BUILD_GUID.tar"
-    fi
+    mkdir -p "/data/cache/$CACHE_KEY/build"
     # Run post-build tasks and capture output
     # Note: Post-build may clean up the builder directory, so we write output directly to log file
     # Use set +e to allow the command to fail without exiting the script