PR Radar

A PR-management dashboard for the mozilla-mobile/firefox-ios team, built to expand to mozilla-central / Phabricator later.

It helps developers keep track of their own PRs, PRs assigned to them, and mentions — and surfaces repository-wide statistics and trends. It can optionally push live updates to a developer's Slack DM.

The whole system is built around a provider abstraction so the same dashboard, stats, and notification logic run over any code-review source. GitHub ships first; Phabricator plugs in later without touching the UI or the stats engine.

---

Feature map

Personal dashboard (per logged-in developer)

• Open PRs where they are a requested reviewer ("assigned").
• Open PRs that @-mention them (body + comments).
• Their own PRs, split into:
  • Waiting for review — no human CHANGES_REQUESTED / human response since last commit.
  • Changes requested — a human requested changes since the last commit.
• Stale PRs: open > X hours (default 48, configurable) with no human response.
• PRs open > 1 week.

Slack integration (opt-in, per developer)

• Bot opens a DM with the developer and posts updates for events tied to their username: their PRs, review-requests, and @-mentions. Each notification type is toggleable.

Stats (repo-wide, filterable by contributor; bots excluded)

• Average time to merge · time to first human comment · average PR size (LOC).
• Closed / rejected PR counts.
• PRs tagged with the "ignore code coverage" label.
• Code-coverage reported by Danger over time.
• All metrics are trended over a configurable time range.

---

Stack

Layer	Choice
Frontend	React + TypeScript + Vite, @primer/react (GitHub's design system), TanStack Query, Recharts
Backend	Python 3.12, FastAPI (async), Pydantic v2, SQLAlchemy 2.0 + Alembic
GitHub	githubkit — async, GitHub App auth, REST + GraphQL + webhooks
Slack	Slack Bolt for Python
Data	Cloud SQL (Postgres). Stat snapshots are BigQuery-export-ready.
Runtime	Cloud Run (API) + Cloud Run Jobs (polling) + Cloud Tasks (async fan-out) + Cloud Scheduler
Secrets	Secret Manager
IaC	Terraform

See ARCHITECTURE.md for the module layout and the provider model.

---

Repo layout

pr-radar/
├── backend/          FastAPI app, providers, services, jobs
├── frontend/         React + Primer dashboard
├── infra/            Terraform for GCP
├── docker-compose.yml  Local dev (postgres + backend + frontend)
└── .env.example

---

Local development

Prereqs: Docker + Docker Compose, Python 3.12, Node 20+.

cp .env.example .env          # fill in the GitHub App + Slack creds
docker compose up --build     # postgres + backend (:8000) + frontend (:5173)

Backend only (against a local postgres):

cd backend
python -m venv .venv && source .venv/bin/activate
pip install -e ".[dev]"
alembic upgrade head
uvicorn app.main:app --reload

Frontend only:

cd frontend
npm install
npm run dev

Frontend mock mode (no backend / creds / DB)

For quickly running and reviewing the UI — and as the basis for UI tests — the frontend has a mock mode powered by MSW. It intercepts every /api/* call and serves fixtures from src/mocks/fixtures.ts, and the mock /api/auth/me bypasses login so you land straight on the dashboard.

cd frontend
npm install
npm run msw:init      # once: writes public/mockServiceWorker.js (committed)
npm run dev:mock      # http://localhost:5173 with fake data, no backend

npm run build:mock produces a static, fully-mocked bundle (handy for design review or hosting a preview).

UI tests (Playwright) run against the same mock mode — no services required:

cd frontend
npx playwright install chromium   # once
npm run test:e2e                  # boots dev:mock automatically, runs specs
npm run test:e2e:ui               # interactive runner

Mock layout:

• src/mocks/fixtures.ts — the fake data (edit to change what the UI shows).
• src/mocks/handlers.ts — MSW route handlers (shared by dev mock + tests).
• src/mocks/browser.ts — the browser worker, started from main.tsx when VITE_MOCK=1.
• tests/e2e/ — Playwright specs; playwright.config.ts boots dev:mock.

---

Configuration

All config is environment-driven (see .env.example and backend/app/config.py). Key knobs:

• STALE_PR_HOURS — default staleness threshold (default 48).
• GITHUB_APP_ID, GITHUB_APP_PRIVATE_KEY, GITHUB_WEBHOOK_SECRET — GitHub App.
• GITHUB_OAUTH_CLIENT_ID / _SECRET — developer login.
• ALLOWED_GITHUB_ORG — org whose members may log in (default mozilla-mobile).
• SLACK_BOT_TOKEN, SLACK_SIGNING_SECRET — Slack app.

---

Status

This is a scaffold. Core domain logic (PR status classification, staleness, stats) is implemented against the normalized model. Anything requiring live credentials (GitHub App calls, Slack posting, OAuth) is wired but marked # TODO(cred) where a real secret / installation is needed. See ARCHITECTURE.md → "Build plan".