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chore: add workflow to auto-delete branches on PR merge + bulk cleanup #1

chore: add workflow to auto-delete branches on PR merge + bulk cleanup

chore: add workflow to auto-delete branches on PR merge + bulk cleanup #1

name: Cleanup Merged PR Branches
on:
# Auto-delete head branch whenever a PR is merged
pull_request:
types: [closed]
# Manual trigger to bulk-delete all existing merged-PR branches
workflow_dispatch:
permissions:
contents: write
jobs:
cleanup-on-merge:
if: github.event_name == 'pull_request' && github.event.pull_request.merged == true
name: Delete branch on PR merge
runs-on: ubuntu-latest
steps:
- name: Delete head branch
uses: actions/github-script@v7
with:
github-token: ${{ secrets.GITHUB_TOKEN }}
script: |
const branch = context.payload.pull_request.head.ref;
const owner = context.repo.owner;
const repo = context.repo.repo;
// Never delete protected branches
const protectedBranches = ['main', 'develop', 'master'];
if (protectedBranches.includes(branch)) {
console.log(`Skipping protected branch: ${branch}`);
return;
}
try {
await github.rest.git.deleteRef({
owner,
repo,
ref: `heads/${branch}`,
});
console.log(`Deleted branch: ${branch}`);
} catch (err) {
if (err.status === 422) {
console.log(`Branch already deleted: ${branch}`);
} else {
throw err;
}
}
bulk-cleanup:
if: github.event_name == 'workflow_dispatch'
name: Bulk delete all merged-PR branches
runs-on: ubuntu-latest
steps:
- name: Delete branches for merged PRs
uses: actions/github-script@v7
with:
github-token: ${{ secrets.GITHUB_TOKEN }}
script: |
const owner = context.repo.owner;
const repo = context.repo.repo;
const protectedBranches = new Set(['main', 'develop', 'master']);
// Collect all head branches from merged PRs (paginate through all pages)
const mergedBranches = new Set();
for await (const response of github.paginate.iterator(
github.rest.pulls.list,
{ owner, repo, state: 'closed', per_page: 100 }
)) {
for (const pr of response.data) {
if (pr.merged_at) {
mergedBranches.add(pr.head.ref);
}
}
}
// Fetch all current branches
const existingBranches = new Set();
for await (const response of github.paginate.iterator(
github.rest.repos.listBranches,
{ owner, repo, per_page: 100 }
)) {
for (const branch of response.data) {
existingBranches.add(branch.name);
}
}
// Delete branches that are in merged PRs and still exist
const toDelete = [...mergedBranches].filter(
b => existingBranches.has(b) && !protectedBranches.has(b)
);
console.log(`Found ${toDelete.length} branches to delete.`);
let deleted = 0;
let failed = 0;
for (const branch of toDelete) {
try {
await github.rest.git.deleteRef({
owner,
repo,
ref: `heads/${branch}`,
});
console.log(`Deleted: ${branch}`);
deleted++;
} catch (err) {
if (err.status === 422) {
console.log(`Already gone: ${branch}`);
} else {
console.error(`Failed to delete ${branch}: ${err.message}`);
failed++;
}
}
}
console.log(`Done. Deleted: ${deleted}, Failed: ${failed}`);
if (failed > 0) {
throw new Error(`Failed to delete ${failed} branch(es). See logs above.`);
}