AGENTS.md — WebHooker

Project Purpose

Cloudflare Worker that receives GitHub webhooks and dispatches processed events to Discord channels/threads via a Durable Object-maintained Gateway connection.

Core pipeline: GitHub Webhook → Worker (verify + filter + format) → Durable Object (Discord Gateway) → Discord

Key Decisions

Runtime: Cloudflare Workers
HTTP framework: Hono
Discord Gateway: optional (DISCORD_GATEWAY_ENABLED=true); only keeps bot online — messages always sent via REST
Storage: Cloudflare KV (tokens, OAuth state, route config, admin sessions)
Signature verification: Web Crypto API (HMAC-SHA256, timing-safe)
GitHub OAuth: octokit + jose (JWT)
Admin WebUI: /admin config console, OAuth-session protected via ADMIN_USER_IDS whitelist
Local dev: wrangler + Miniflare

Architecture

src/
├── index.ts              # CF Workers entry (fetch + scheduled), exports DiscordGateway DO
├── types.ts              # Env, Config, Route, Filter, WebhookEvent, FormattedMessage
├── config.ts             # loadRoutes/saveRoutes (KV config:routes, cache w/ 60s TTL), loadConfig from env
├── server.ts             # Hono app: /health, /webhook, mounts /auth, /admin + /
├── webhook.ts            # HMAC verify (Web Crypto), parseEvent, extractBranch, matchRoute
├── discord.ts            # Dispatch via REST (or DO RPC when gateway enabled), initGateway (scheduled)
├── discord-rest.ts       # Discord REST sendMessage with retry + rate-limit handling
├── discord-gateway.ts    # Optional Durable Object: Discord Gateway WS, heartbeat, channel cache, send
├── formatter.ts          # 23 event formatters + generic fallback (~1380 lines)
├── github-oauth.ts       # OAuth URL, callback token exchange, getUserOctokit
├── oauth-routes.ts       # GET /auth/github, callback (sets admin session if redirect=/admin), DELETE /token/:userId
├── action-routes.ts      # POST /api/comment|merge|react (Bearer token auth via KV lookup)
├── admin-routes.ts       # /admin UI + GET/PUT /admin/api/routes (session + ADMIN_USER_IDS auth, validation)
├── admin-session.ts      # Session CRUD (KV session:{id}), isAdminUser, cookie helpers
├── admin-ui.ts           # ADMIN_HTML: single-file config console (vanilla HTML/CSS/JS)
├── token-store.ts        # KV-based token CRUD with findUserIdByToken reverse lookup
└── log.ts                # JSON console logger (info/warn/error/fatal)

Responsibilities

Verify GitHub webhook signatures (Web Crypto HMAC-SHA256)
Filter events by: event type, repo name, actor, action, branch, keyword (regex supported)
Format 23+ event types as Discord embeds
Route messages to Discord channels/threads via Durable Object RPC
Maintain Discord Gateway connection with heartbeat and alarm-based keepalive

Development

npx wrangler dev      # Local dev (Miniflare)
npm run typecheck     # Type checking
npm run lint          # ESLint

Configuration

Local dev: .dev.vars (wrangler reads this for env bindings)
Production: wrangler secret put <NAME> for each secret
Routes: KV key config:routes (JSON array); 7 defaults on first boot
KV namespace: Required binding for token/state/config storage

Deployment

npx wrangler secret put GITHUB_WEBHOOK_SECRET
npx wrangler secret put DISCORD_TOKEN
npx wrangler kv namespace create KV
# Update wrangler.jsonc with KV ID
npx wrangler deploy

3.5 KiB Raw Blame History