telegram

Our new telegram bot.

Quick start

1. run Redis instance locally with docker:

   docker run -p 6379:6379 --name pn-tg-redis -d redis

2. install dependencies

   pnpm install

3. run

   pnpm run dev

Maybe useful references

• How to send private messages

Campaign spam protection

The campaign guard detects the short recruitment and fraud campaigns currently sent across the network. It uses normalized message signatures, a narrow lure lexicon, Telegram mentions and links, contact-card names, inline-bot metadata, URL domains, recent joins, and repetition across distinct authors and chats. It never bans on language, an undocumented Telegram user-ID cutoff, a phone prefix, or profile metadata alone.

Protection and the first-post join gate are always active; no feature-specific environment variables are needed. The guard replaces the broad non-Latin rule. It mutes uncertain matches for moderator review and starts BanAll for confirmed campaigns. Thresholds are defined in src/middlewares/campaign-spam/runtime-config.ts.

The guard learns a signature after either three distinct authors send it in two chats within ten minutes, or four distinct authors send it in two chats within four hours. The slow tier keeps one-chat repetition below BanAll to avoid treating a copied local notice as a network campaign. Redis retains hashed signatures, handles, URL domains, contact phone numbers, display-name fingerprints, and campaign user IDs for 30 days. Raw message retention does not change.

High-precision lures such as 收米, 日入, 上车吃肉, 洗资, 聘群演, 注册送, and 两分钟一单 can quarantine a Han-script message without requiring an @mention. Broad terms such as 米, 学籍, or 群演 do not match alone. Contact cards are inspected through their display name and phone number, but the phone is HMAC-protected before any evidence is stored.

Examples:

• Match and quarantine: 来收米 日入9K, 上车吃肉🧧, or a contact named PG电子来注册送28U.
• Match on a restricted first post: Han text containing an @mention, t.me link, or inline button.
• Match and BanAll: the same normalized campaign signature from 4 authors in 2 chats over 4 hours.
• Do not match: 大家好，我是交换生，请问今天的课程在哪个教室？.
• Do not match: an established member sharing a contact named 王小明.

Reputation is learned from confirmed campaigns and moderator decisions. The join gate also checks each applicant's existing BanAll and UnbanAll audit history, so previously banned targets work immediately.

Quarantined messages create an action-required review with Confirm BanAll and Release buttons. Confirming trains the signature, account, and display-name reputation. Releasing removes learned reputation and restores permissions. Unrelated BanAll, unban, and unmute actions do not alter campaign reputation. Retained evidence includes hashes for button URLs and domains, mention targets, and inline-bot usernames. Telemetry records the classifier version, actual join outcomes, first-post catches, and campaign review feedback.

Persisted identifiers use versioned HMAC-SHA-256 fingerprints keyed by the existing bot token. Rotating the bot token starts a fresh learned-reputation fingerprint space; BanAll audit history still applies. Review callback state is authenticated and encrypted before the menu adapter stores it.

The bot needs can_invite_users and can_restrict_members in every managed group. The bot gives ordinary requested and direct joins text-only permissions. An ordinary first-post restriction lasts for up to seven days and is removed after the first allowed message, so waiting beyond the freshness window does not bypass first-post review. The gate declines exact campaign user IDs and exact display-name fingerprints repeated by three confirmed campaign accounts. A partial exact match or a no-username profile containing several campaign markers stays read-only for moderator review; one benign post and the ordinary timeout cannot clear that review hold. Review permissions, callback data, pending state, and replay protection share a bounded 365-day lifecycle. If the review item cannot be delivered, the account falls back to the ordinary first-post path. Profile metadata alone never triggers an automatic decline.

Console logs use the [CampaignSpam] prefix through the existing Pino logger. They report startup, suspicious and first-post classifications with reasons and cross-chat counts, join decisions and restrictions, first-post releases, review delivery, local bans, network BanAll starts, moderator decisions, and dependency failures. Identifiers let operators correlate actions without logging raw message text, contact details, or the fingerprint secret.

IdP authorization

The bot uses @polinetwork/auth-kit to obtain a cached client_credentials token with private_key_jwt. Register a separate telegram-bot client in the IdP and link it to the backend resource. Its scopes are backend:tg:read, backend:tg:ingest, backend:tg:groups:sync, backend:tg:audit, backend:tg:act-as and backend:tg:events. The IdP stores its public JWKS; inject the private JWK from the bot's Key Vault as OAUTH_BOT_PRIVATE_JWK (JSON with kid, alg and private key material). Never put the key in the repository or logs.

IDP_PUBLIC_URL, OAUTH_BACKEND_RESOURCE_URI, OAUTH_BOT_CLIENT_ID and OAUTH_BOT_PRIVATE_JWK are required; startup fails without them. The bot never calls the backend anonymously. IDP_INTERNAL_URL optionally routes token requests inside the cluster; assertion audiences retain the public token URL. BACKEND_URL continues to be a host and port, without a URL scheme, matching the existing backend transport.

Each human update gets an isolated actor client (ctx.backend, X-PN-Actor: telegram:<id>). Service-only operations, including buffered message/user ingestion, group synchronization, ban-all execution and audit writes, use serviceBackend. Commands running inside grammY conversations reconstruct the actor client from their sender because conversation state cannot persist a tRPC client. A batch belongs to one client and cannot mix actors. Backend calls have a 10-second transport timeout; a 401 invalidates the token and retries once. Other errors never fall back to anonymous transport. The socket authenticates with auth.token; a server expiry disconnect triggers reconnect, and rejected handshakes invalidate the token with retry backoff.

Commands, callback menus and target checks act on the IdP permissions resolved through tg.access.resolve (RFC v3 §10.2). An unavailable actor check denies actions; native chat administrators (Telegram status administrator or creator) retain the documented chat-local shortcut, which replaces the removed tg_group_admins table. Immunity (tg:immune) applies to every ban-all entry point at enqueue; jobs already accepted continue without permission rechecks. /getroles lists the IdP permissions. Roles are managed in the IdP, so the bot no longer has /addrole, /delrole or /link.

Moderation audit records use tg.auditLog.record and a Redis outbox with stable idempotency keys, actor IDs and the basis (idp_permission, telegram_chat_admin, automatic, telegram_ui). Automatic actions have no human actor; the backend flags idp_permission records that the snapshot does not back for review. Redis hashes and a due-time sorted set are changed atomically. Backend outages retry with capped exponential backoff; permanent input errors move to audit-outbox:dead for inspection. Enable Redis AOF, use persistent storage and a non-evicting policy for the audit data. Shutdown keeps Redis alive until the runner, buffered storage and module workers stop. If Redis cannot store a record, the bot attempts direct delivery; if both systems fail the full record is logged as lost. This fallback is best effort: durability requires functioning persistent Redis, and a crash between a Telegram action and its outbox write can still lose that action's audit record. Ban-all flow creation persists audit recovery data atomically with the job. Audit delivery starts only after a confirmed insertion; caller retries and the resumed orchestrator deliver the same key, so a crash in between is recovered without duplicate history. Older jobs without this recovery data keep their original behavior.

Grant socket messages accept both the legacy adminId and the new { sub, telegramId, displayName } actor. A dashboard user without a linked Telegram account can therefore be shown by display name in the grants topic.

Validate token acquisition, service-only ingestion, actor isolation, socket expiry/reconnect and audit retry/deduplication in a test environment. Unit tests do not verify real IdP, Telegram or Key Vault connectivity. Keep Redis persistence so pending audits survive a rollback/restart. Bot images from before this cleanup still call the backend anonymously; rolling back to one needs the backend's LEGACY_ANONYMOUS=allow.