fix: validate registry credentials before docker login

Problem: Registry login fails silently if secrets aren't configured
- Empty FORGEJO_REGISTRY_USER/TOKEN → docker login hangs/fails
- No clear error message about missing credentials

Solution: Add validation step that checks credentials exist
- Fails early with clear error if secrets missing
- Shows how to configure in repo settings
- Uses direct secret injection (not via env vars)
- Isolates docker config to /tmp/docker-config

Result: CI will fail fast with actionable error if credentials missing

.gitea/workflows/build.yaml

@@ -49,27 +49,35 @@ jobs:
           SHORT_SHA=$(git rev-parse --short HEAD)
           echo "short_sha=${SHORT_SHA}" >> $GITHUB_OUTPUT
 
+      - name: Validate registry credentials
+        run: |
+          if [ -z "${{ secrets.FORGEJO_REGISTRY_USER }}" ] || [ -z "${{ secrets.FORGEJO_REGISTRY_TOKEN }}" ]; then
+            echo "❌ ERROR: Registry secrets not configured"
+            echo "Set FORGEJO_REGISTRY_USER and FORGEJO_REGISTRY_TOKEN in repo settings"
+            exit 1
+          fi
+          echo "✓ Registry credentials configured"
+
       - name: Registry login
         run: |
-          echo "${REGISTRY_TOKEN}" | docker login "${REGISTRY}" \
+          echo "${{ secrets.FORGEJO_REGISTRY_TOKEN }}" | docker login "${{ env.REGISTRY }}" \
-            --username "${REGISTRY_USER}" --password-stdin
+            --username "${{ secrets.FORGEJO_REGISTRY_USER }}" --password-stdin
         env:
-          REGISTRY_USER: ${{ secrets.FORGEJO_REGISTRY_USER }}
+          DOCKER_CONFIG: /tmp/docker-config
-          REGISTRY_TOKEN: ${{ secrets.FORGEJO_REGISTRY_TOKEN }}
 
       - name: Build Docker image
         run: |
           docker build --no-cache \
-            -t "${IMAGE}:${{ steps.sha.outputs.short_sha }}" \
+            -t "${{ env.IMAGE }}:${{ steps.sha.outputs.short_sha }}" \
-            -t "${IMAGE}:latest" \
+            -t "${{ env.IMAGE }}:latest" \
             -f Dockerfile \
             .
 
       - name: Push Docker image
         run: |
-          docker push "${IMAGE}:${{ steps.sha.outputs.short_sha }}"
+          docker push "${{ env.IMAGE }}:${{ steps.sha.outputs.short_sha }}"
-          docker push "${IMAGE}:latest"
+          docker push "${{ env.IMAGE }}:latest"
-          echo "✓ Image pushed: ${IMAGE}:${{ steps.sha.outputs.short_sha }}"
+          echo "✓ Image pushed: ${{ env.IMAGE }}:${{ steps.sha.outputs.short_sha }}"
 
       - name: Prune unused images
         run: docker image prune -a --force 2>&1 | tail -3 || true

REGISTRY_SETUP.md

@@ -0,0 +1,78 @@
+# Forgejo Registry Secrets Configuration
+
+## One-Time Setup (Org Level)
+
+All repos in the `rock` org share the same Forgejo registry credentials.
+
+### Configure at Organization Level
+
+1. Navigate to: https://forgejo.riotpiao.com/rock
+2. Click Settings (gear icon)
+3. Go to: Actions → Secrets
+4. Add these org-level secrets:
+   - **Name**: `FORGEJO_REGISTRY_USER`
+     **Value**: `rock`
+   
+   - **Name**: `FORGEJO_REGISTRY_TOKEN`
+     **Value**: `<your-forgejo-token>`
+
+### Get Your Forgejo Token
+
+1. Go to: https://forgejo.riotpiao.com/user/settings/applications
+2. Click "Generate New Token"
+3. Set scopes: `api`, `read:registry`, `write:registry`
+4. Copy the token value into the secret
+
+## Inheritance
+
+Once org-level secrets are set:
+- ✅ All repos in `rock` org automatically inherit them
+- ✅ No per-repo configuration needed
+- ✅ Workflows reference via `${{ secrets.FORGEJO_REGISTRY_USER }}`
+
+## Validation
+
+Each repo's CI workflow includes a validation step:
+
+```yaml
+- name: Validate registry credentials
+  run: |
+    if [ -z "${{ secrets.FORGEJO_REGISTRY_USER }}" ] || [ -z "${{ secrets.FORGEJO_REGISTRY_TOKEN }}" ]; then
+      echo "❌ ERROR: Registry secrets not configured"
+      echo "Set FORGEJO_REGISTRY_USER and FORGEJO_REGISTRY_TOKEN in org settings"
+      exit 1
+    fi
+    echo "✓ Registry credentials configured"
+```
+
+If secrets are missing, the validation step will fail with a clear error message pointing to this setup process.
+
+## Affected Repositories
+
+The following repos use these shared org-level secrets in their CI workflows:
+
+- rock/riotpiao.com
+- rock/homelab-frontend
+- rock/poimen-workflows
+- rock/poimen-memory
+- rock/kmsvc-manage
+
+All use the unified CI pattern:
+- `test` job: runs on all branches + PRs (no registry access)
+- `build-push` job: runs on main push only (requires registry credentials)
+
+## Troubleshooting
+
+### "Registry secrets not configured" error
+
+If CI fails with this error:
+1. Check org settings: https://forgejo.riotpiao.com/rock/settings/actions/secrets
+2. Verify both secrets exist and are not empty
+3. Re-trigger the workflow by pushing to main
+
+### "unauthorized" from docker login
+
+If you get `error response from daemon: unauthorized`:
+1. Check the token value is correct (copy-paste carefully)
+2. Verify token has `read:registry` and `write:registry` scopes
+3. Generate a new token if the old one expired