From 3facc85e092791d3d0997cc9ed41a755d75f1bc8 Mon Sep 17 00:00:00 2001
From: "n8n-cat-bot[bot]" <283985454+n8n-cat-bot[bot]@users.noreply.github.com>
Date: Wed, 27 May 2026 21:45:17 +0100
Subject: [PATCH] ci: Add build-on-miss fallback to E2E docker image load
 (#31232)

Co-authored-by: n8n-cat-bot[bot] <n8n-cat-bot[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>
---
 .github/actions/load-n8n-docker/action.yml | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/.github/actions/load-n8n-docker/action.yml b/.github/actions/load-n8n-docker/action.yml
index 688854358e3..5999c9da22d 100644
--- a/.github/actions/load-n8n-docker/action.yml
+++ b/.github/actions/load-n8n-docker/action.yml
@@ -4,9 +4,14 @@
 #
 # After this action runs, `n8nio/n8n:local` and `n8nio/runners:local` are
 # present on the runner.
+#
+# If the cache entry has been evicted (e.g. Blacksmith cache thrash between
+# prepare-docker and slow shards), the action falls back to invoking
+# build-n8n-docker, which leaves both images tagged in dockerd and re-saves
+# the tarball to cache as a side effect.
 
 name: 'Load n8n Docker images from cache'
-description: 'Restores the zstd-compressed n8n + runners image tarball from the variant+SHA-keyed GHA cache and loads both images into the local docker daemon.'
+description: 'Restores the zstd-compressed n8n + runners image tarball from the variant+SHA-keyed GHA cache and loads both images into the local docker daemon. Falls back to rebuilding on cache miss.'
 
 inputs:
   build-variant:
@@ -18,12 +23,25 @@ runs:
   using: 'composite'
   steps:
     - name: Restore image tarball from cache
+      id: restore
       uses: actions/cache/restore@640a1c2554105b57832a23eea0b4672fc7a790d5 # v4.2.3
       with:
         key: n8n-docker-image-${{ inputs.build-variant }}-${{ github.sha }}
         path: /tmp/n8n-image.tar.zst
-        fail-on-cache-miss: true
 
     - name: Load n8n and runners images into docker
+      if: steps.restore.outputs.cache-hit == 'true'
       shell: bash
       run: zstd -d -c /tmp/n8n-image.tar.zst | docker load
+
+    - name: Warn on cache miss
+      if: steps.restore.outputs.cache-hit != 'true'
+      shell: bash
+      run: |
+        echo "::warning::Cache miss for n8n-docker-image-${{ inputs.build-variant }}-${{ github.sha }} (SHA ${{ github.sha }}); falling back to rebuild via build-n8n-docker."
+
+    - name: Rebuild image on cache miss
+      if: steps.restore.outputs.cache-hit != 'true'
+      uses: ./.github/actions/build-n8n-docker
+      with:
+        build-variant: ${{ inputs.build-variant }}