GitHub/GitLab Developer Automation

Chapter 12: GitHub / GitLab Developer Automation

Code repositories are the engineering team's central hub, but GitHub/GitLab notifications are noisy and siloed from collaboration tools. n8n bridges this gap with GitHub Trigger, GitLab Webhooks, and GitHub/GitLab action nodes. This chapter covers four core DevOps automation scenarios: PR auto-reviewer assignment, Issue-to-Notion sync, CI/CD status broadcasting, and overdue code review reminders.

GitHub Trigger: Listening to Repository Events

The GitHub Trigger node uses GitHub Webhooks for real-time event delivery. n8n automatically registers and removes the webhook when you activate/deactivate the workflow (requires a PAT with repo and admin:repo_hook scopes).

Key Event Types

GitLab Webhook: MR Event Triggers

GitLab lacks a dedicated n8n Trigger node — use a generic Webhook node instead. Copy the n8n Webhook URL into GitLab project Settings → Webhooks, check the desired events (Merge Request, Pipeline, Issues), and optionally add a Secret Token. In n8n, validate the X-Gitlab-Token header in a Code node. Key MR payload fields: object_kind, object_attributes.state (opened/merged/closed), object_attributes.url.

Project: PR Created → Auto-Assign Reviewer → Feishu Notification

Workflow: GitHub Trigger (pull_request, action=opened) → IF (skip bot PRs like dependabot) → Code node (round-robin reviewer selection using Workflow Static Data) → GitHub node (Request Review) → HTTP Request (Feishu interactive card to reviewer with PR title, changed files count, and direct link).

// Feishu PR notification card body snippet
{
  "msg_type": "interactive",
  "card": {
    "header": {
      "title": { "tag": "plain_text", "content": "New PR Awaiting Your Review" },
      "template": "blue"
    },
    "elements": [{
      "tag": "action",
      "actions": [{
        "tag": "button",
        "text": { "tag": "plain_text", "content": "Open PR" },
        "type": "primary",
        "url": "={{ $json.pull_request.html_url }}"
      }]
    }]
  }
}

Project: Issue Closed → Update Notion Task Status

GitHub Trigger (issues, filter action = "closed") → Notion Get Many (find page where "GitHub Issue #" = {{ $json.issue.number }}) → IF (page exists?) → Notion Update Page (set Status = "Done", Closed At = now) → optional Feishu notification to PM.

CI/CD Status Broadcast

GitHub Trigger (workflow_run, action = "completed") → IF (branch is "main"?) → Switch on conclusion (success / failure) → HTTP Request to Feishu with green success card or red failure card (@oncall on failure).

// workflow_run event payload key fields
{
  "action": "completed",
  "workflow_run": {
    "name": "CI",
    "conclusion": "success",
    "head_branch": "main",
    "html_url": "https://github.com/org/repo/actions/runs/123"
  }
}

Code Review Reminder: 24h Overdue Alert

Cron (hourly) → GitHub node (List open PRs with requested reviewers) → Code node (filter PRs older than 24h without a review) → Loop Over Items → HTTP Request (Feishu @reviewer reminder with PR title and wait duration).

Prevent reminder spam: Track already-notified PR IDs in Workflow Static Data. Check before sending — skip any PR notified today to avoid hourly bombardment.