Skip to content

Dependabot Auto Merge #371

Dependabot Auto Merge

Dependabot Auto Merge #371

name: Dependabot Auto Merge
on:
workflow_run:
workflows:
- "Build and Push Image"
- "CI"
- "CodeQL"
- "Commit Lint"
- "Copilot"
- "Dependabot Updates"
- "Deploy to Cloudflare Pages"
- "Deploy to Cloudflare Workers"
- "Deploy to EdgeOne Pages"
- "Deploy to Vercel"
- "Sync to Pages and Functions"
types:
- completed
workflow_dispatch:
concurrency:
group: ${{ github.workflow }}-${{ github.event.workflow_run.head_branch || github.run_id }}
cancel-in-progress: false
permissions:
contents: write
pull-requests: write
checks: read
statuses: read
jobs:
merge:
name: Auto-merge Dependabot PRs
runs-on: ubuntu-latest
timeout-minutes: 10
steps:
- name: Merge Dependabot PRs when checks pass
uses: actions/github-script@v9
with:
script: |
const owner = context.repo.owner;
const repo = context.repo.repo;
const successfulCheckConclusions = new Set(["success", "skipped", "neutral"]);
const successfulStatusStates = new Set(["success"]);
const wait = (ms) => new Promise((resolve) => setTimeout(resolve, ms));
const latestBy = (items, keyOf, timeOf) => {
const latest = new Map();
for (const item of items) {
const key = keyOf(item);
const itemTime = new Date(timeOf(item) || 0).getTime();
const existing = latest.get(key);
const existingTime = existing ? new Date(timeOf(existing) || 0).getTime() : -1;
if (!existing || itemTime >= existingTime) {
latest.set(key, item);
}
}
return [...latest.values()];
};
const findCandidatePulls = async () => {
const branch = context.payload.workflow_run?.head_branch;
if (context.eventName === "workflow_run" && branch) {
const { data: pulls } = await github.rest.pulls.list({
owner,
repo,
state: "open",
head: owner + ":" + branch,
per_page: 10,
});
return pulls.filter((pr) => pr.user?.login === "dependabot[bot]");
}
const pulls = await github.paginate(github.rest.pulls.list, {
owner,
repo,
state: "open",
per_page: 100,
});
return pulls.filter((pr) => pr.user?.login === "dependabot[bot]");
};
const getMergeablePullRequest = async (pull_number) => {
for (let attempt = 1; attempt <= 6; attempt += 1) {
const { data: pr } = await github.rest.pulls.get({ owner, repo, pull_number });
if (pr.mergeable !== null) {
return pr;
}
core.info("PR #" + pull_number + " mergeability is still being computed; retry " + attempt + "/6.");
await wait(5000);
}
const { data: pr } = await github.rest.pulls.get({ owner, repo, pull_number });
return pr;
};
const getSignalState = async (sha) => {
const checkRuns = await github.paginate(github.rest.checks.listForRef, {
owner,
repo,
ref: sha,
per_page: 100,
});
const statuses = await github.paginate(github.rest.repos.listCommitStatusesForRef, {
owner,
repo,
ref: sha,
per_page: 100,
});
const latestChecks = latestBy(
checkRuns.filter((run) => run.name !== "Dependabot Auto Merge"),
(run) => (run.app?.slug || "unknown") + ":" + run.name,
(run) => run.completed_at || run.started_at || run.created_at,
);
const latestStatuses = latestBy(statuses, (status) => status.context, (status) => status.updated_at || status.created_at);
const pendingChecks = latestChecks.filter((run) => run.status !== "completed");
const failedChecks = latestChecks.filter(
(run) => run.status === "completed" && !successfulCheckConclusions.has(String(run.conclusion || "").toLowerCase()),
);
const failedStatuses = latestStatuses.filter((status) => !successfulStatusStates.has(String(status.state || "").toLowerCase()));
return {
totalSignals: latestChecks.length + latestStatuses.length,
pendingChecks,
failedChecks,
failedStatuses,
};
};
const { data: repository } = await github.rest.repos.get({ owner, repo });
const mergeMethods = [];
if (repository.allow_merge_commit) mergeMethods.push("merge");
if (repository.allow_squash_merge) mergeMethods.push("squash");
if (repository.allow_rebase_merge) mergeMethods.push("rebase");
if (mergeMethods.length === 0) {
core.info("This repository has no enabled pull request merge methods.");
return;
}
const pulls = await findCandidatePulls();
if (pulls.length === 0) {
core.info("No open Dependabot PRs to evaluate.");
return;
}
for (const candidate of pulls) {
const pull_number = candidate.number;
const pr = await getMergeablePullRequest(pull_number);
if (pr.user?.login !== "dependabot[bot]") {
core.info("PR #" + pull_number + " is no longer a Dependabot PR.");
continue;
}
if (pr.state !== "open" || pr.draft) {
core.info("PR #" + pull_number + " is not an open, ready PR.");
continue;
}
if (pr.mergeable !== true) {
core.info("PR #" + pull_number + " is not currently mergeable.");
continue;
}
const signalState = await getSignalState(pr.head.sha);
if (signalState.totalSignals === 0) {
core.info("PR #" + pull_number + " has no checks or statuses yet; skipping.");
continue;
}
if (signalState.pendingChecks.length > 0) {
core.info("PR #" + pull_number + " still has pending checks: " + signalState.pendingChecks.map((run) => run.name).join(", ") + ".");
continue;
}
if (signalState.failedChecks.length > 0 || signalState.failedStatuses.length > 0) {
const failedChecks = signalState.failedChecks.map((run) => run.name + "=" + run.conclusion).join(", ");
const failedStatuses = signalState.failedStatuses.map((status) => status.context + "=" + status.state).join(", ");
core.info("PR #" + pull_number + " is not green. Checks: " + (failedChecks || "none") + ". Statuses: " + (failedStatuses || "none") + ".");
continue;
}
let merged = false;
let lastError = null;
for (const merge_method of mergeMethods) {
try {
await github.rest.pulls.merge({ owner, repo, pull_number, merge_method });
core.info("Merged Dependabot PR #" + pull_number + " with " + merge_method + ".");
merged = true;
break;
} catch (error) {
lastError = error;
if (error.status === 403 || error.status === 405 || error.status === 409) {
core.info("Cannot merge PR #" + pull_number + " with " + merge_method + ": " + error.message);
continue;
}
throw error;
}
}
if (!merged) {
core.info("PR #" + pull_number + " could not be merged: " + (lastError?.message || "unknown error") + ".");
continue;
}
if (pr.head.repo?.full_name === owner + "/" + repo) {
try {
await github.rest.git.deleteRef({ owner, repo, ref: "heads/" + pr.head.ref });
core.info("Deleted branch " + pr.head.ref + ".");
} catch (error) {
core.info("Could not delete branch " + pr.head.ref + ": " + error.message);
}
}
}