sync-plumbing-workflows

name	sync-plumbing-workflows
description	Sync reusable workflow digests from tektoncd/plumbing into this repo's .github/workflows. Use when updating pinned SHA digests for workflows sourced from tektoncd/plumbing (e.g. _chatops_retest.yml, _cherry-pick-command.yaml), or when checking whether local workflow pins are behind the current main branch of the plumbing repo.
license	Apache-2.0
compatibility	Requires git, gh CLI, sed (GNU or BSD), and internet access to github.com
metadata	{"project":"tekton-pruner"}
allowed-tools	Bash(git:*) Bash(gh api:*) Bash(grep:*) Bash(sed:*) Read Glob

Sync Plumbing Workflow Digests

tekton-pruner references reusable workflows from tektoncd/plumbing. These are pinned to SHA digests for supply-chain security. This skill resolves the latest commit SHA on main for each referenced plumbing workflow and updates the pins in .github/workflows/.

Background

Workflow references look like:

uses: tektoncd/plumbing/.github/workflows/_chatops_retest.yml@1cf2292a30268252a734b413b8a44f15c04d1de8 # main
uses: tektoncd/plumbing/.github/workflows/_cherry-pick-command.yaml@9f8e1781d5cc431e5c95190a9fc14dfba1cec391 # main

The SHA after @ must be the full 40-character commit hash. The # main comment documents the intended branch.

Process

1. Find all plumbing workflow references in this repo

grep -rn "tektoncd/plumbing/.github/workflows" .github/workflows/

Expected output lists each file and the current pinned SHA.

2. Resolve the latest commit SHA on plumbing main

Use the GitHub API (no clone needed):

gh api repos/tektoncd/plumbing/commits/main --jq '.sha'

This returns the HEAD SHA of main. All reusable workflows in plumbing are versioned together — there is no per-file SHA; the commit SHA covers the whole repo tree.

To get the SHA for a specific workflow path (confirms the file still exists at that commit):

# Check that the workflow file exists on main
gh api "repos/tektoncd/plumbing/contents/.github/workflows/_chatops_retest.yml?ref=main" --jq '.sha'

gh api "repos/tektoncd/plumbing/contents/.github/workflows/_cherry-pick-command.yaml?ref=main" --jq '.sha'

Note: The .sha from the contents API is the blob SHA (not the commit SHA). Use the commit SHA from step 2 for the uses: pin — that is what GitHub Actions validates.

3. Compare current pins to latest

LATEST=$(gh api repos/tektoncd/plumbing/commits/main --jq '.sha')
echo "Latest plumbing main: $LATEST"
echo ""
echo "Current pins in this repo:"
grep -rh "tektoncd/plumbing" .github/workflows/ | grep -oE '@[0-9a-f]{40}' | sort -u

If the current pin already matches $LATEST, no update is needed.

4. Update all plumbing workflow pins

Replace all occurrences of the old SHA with the new one across every workflow file:

OLD=$(grep -rh "tektoncd/plumbing" .github/workflows/ | grep -oE '@[0-9a-f]{40}' | sort -u | head -1)
NEW=$(gh api repos/tektoncd/plumbing/commits/main --jq '.sha')

echo "Updating $OLD → $NEW"

# Dry run first
grep -rln "tektoncd/plumbing" .github/workflows/

# Apply (portable across macOS and Linux)
for f in $(grep -rln "tektoncd/plumbing" .github/workflows/); do
  sed -i.bak "s|tektoncd/plumbing/.github/workflows/\(.*\)@${OLD}|tektoncd/plumbing/.github/workflows/\1@${NEW}|g" "$f"
  rm -f "${f}.bak"
  echo "Updated $f"
done

5. Verify the changes

grep -rn "tektoncd/plumbing" .github/workflows/

All occurrences should now show the new SHA, with # main comment preserved.

6. Commit the update

Use a conventional commit message:

git add .github/workflows/
git commit -m "chore: update tektoncd/plumbing workflow pins to $(gh api repos/tektoncd/plumbing/commits/main --jq '.sha[0:12]')"

Open a PR following normal contribution process.

Checking Other Pinned Actions

Other pinned actions in .github/workflows/ (e.g. actions/checkout, actions/setup-go, golangci/golangci-lint-action) are managed separately. This skill covers only tektoncd/plumbing references.

To audit all pinned actions in the repo at once:

grep -rh "uses:" .github/workflows/ | grep -v "^#" | sort -u

For a full dependency update including non-plumbing actions, use Dependabot or the zizmor security scanner already configured in .github/workflows/zizmor.yaml.

References

• tektoncd/plumbing — shared workflow sources
• GitHub Actions: reusable workflows
• OpenSSF Scorecard: pinned dependencies