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Co-authored-by: Arif Kobel <arif.kobel@phorax.com>
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…ounce, concurrent) (#277) * feat: add concurrency strategies for overlapping messages (queue, debounce, concurrent) ## Problem When multiple messages arrive on the same thread while a handler is still processing, the SDK has only one behavior: **lock-and-drop**. The incoming message is silently discarded (or force-released, which creates uncontrolled concurrency). This is insufficient for most real-world use cases: - **AI chatbots** lose user follow-up messages sent while the model is streaming - **Customer support bots** miss messages entirely, breaking conversation flow - **Collaborative editing bots** need to coalesce rapid corrections into one action ## Solution Introduce a new `concurrency` option on `ChatConfig` with four strategies: ### `'drop'` (default, backward-compatible) Existing behavior. Lock acquired or `LockError` thrown. No changes. ### `'queue'` Messages that arrive while a handler is running are enqueued in the state adapter. When the current handler finishes, the queue is drained: **only the latest message is dispatched**, with all intermediate messages provided as `context.skipped`. This gives the handler full visibility into what happened while it was busy, without forcing it to re-process every message sequentially. ```typescript const chat = new Chat({ concurrency: 'queue', // ... }); chat.onNewMention(async (thread, message, context) => { if (context && context.skipped.length > 0) { // "You sent 4 messages while I was thinking. Responding to your latest." const allMessages = [...context.skipped, message]; // Pass all messages to the LLM for full context } }); ``` Flow: ``` A arrives → acquire lock → process A B arrives → lock busy → enqueue B C arrives → lock busy → enqueue C D arrives → lock busy → enqueue D A done → drain: [B, C, D] → handler(D, { skipped: [B, C] }) D done → queue empty → release lock ``` ### `'debounce'` Every message (including the first) starts or resets a debounce timer. Only the **final message in a burst** is processed. The lock-holding function stays alive through `waitUntil` during the debounce window. ```typescript const chat = new Chat({ concurrency: { strategy: 'debounce', debounceMs: 1500 }, // ... }); ``` Flow: ``` A arrives → acquire lock → store A as pending → sleep(debounceMs) B arrives → lock busy → overwrite pending with B (A dropped) C arrives → lock busy → overwrite pending with C (B dropped) ... debounceMs elapses with no new message ... → process C → release lock ``` ### `'concurrent'` No locking at all. Every message is processed immediately in its own handler invocation. Suitable for stateless handlers (lookups, translations) where thread ordering doesn't matter. ```typescript const chat = new Chat({ concurrency: 'concurrent', // ... }); ``` ## API Surface ### ChatConfig ```typescript interface ChatConfig { concurrency?: ConcurrencyStrategy | ConcurrencyConfig; /** @deprecated Use `concurrency` instead */ onLockConflict?: 'force' | 'drop' | ((threadId, message) => ...); } type ConcurrencyStrategy = 'drop' | 'queue' | 'debounce' | 'concurrent'; interface ConcurrencyConfig { strategy: ConcurrencyStrategy; maxQueueSize?: number; // Default: 10 onQueueFull?: 'drop-oldest' | 'drop-newest'; // Default: 'drop-oldest' queueEntryTtlMs?: number; // Default: 90_000 (90s) debounceMs?: number; // Default: 1500 maxConcurrent?: number; // Default: Infinity } ``` ### MessageContext (new, passed to handlers) ```typescript interface MessageContext { skipped: Message[]; // Intermediate messages, chronological totalSinceLastHandler: number; // skipped.length + 1 } ``` All handler types (`MentionHandler`, `MessageHandler`, `SubscribedMessageHandler`, `DirectMessageHandler`) now accept an optional `MessageContext` as their last parameter. Existing handlers that don't use it are unaffected. ### StateAdapter (new methods) ```typescript interface StateAdapter { enqueue(threadId: string, entry: QueueEntry, maxSize: number): Promise<number>; dequeue(threadId: string): Promise<QueueEntry | null>; queueDepth(threadId: string): Promise<number>; } ``` Implemented across all four state adapters: - **MemoryStateAdapter**: in-process array - **RedisStateAdapter**: Lua script (RPUSH + LTRIM + PEXPIRE) - **IoRedisStateAdapter**: same Lua approach - **PostgresStateAdapter**: new `chat_state_queues` table with atomic dequeue ## Architecture `handleIncomingMessage` was refactored into composable pieces: - `dispatchToHandlers()` — shared handler dispatch logic (mention detection, subscription routing, pattern matching). Extracted from the old monolithic method so all strategies reuse it. - `handleDrop()` — original lock-or-fail path (preserves `onLockConflict` compat) - `handleQueueOrDebounce()` — enqueue if busy, drain or debounce after - `handleConcurrent()` — skip locking entirely - `drainQueue()` — collect all pending, dispatch latest with skipped context - `debounceLoop()` — sleep/check/repeat until no new messages arrive ## Queue Entry TTL Queued messages have a configurable TTL (`queueEntryTtlMs`, default 90s). Stale entries are discarded on dequeue with a `message-expired` log event. This prevents unbounded accumulation and ensures handlers don't process messages that are no longer relevant. ## Observability All strategies emit structured log events at `info` level: | Event | Strategy | Data | |-----------------------|------------------|---------------------------------------| | `message-queued` | queue | threadId, messageId, queueDepth | | `message-dequeued` | queue, debounce | threadId, messageId, skippedCount | | `message-dropped` | drop, queue | threadId, messageId, reason | | `message-expired` | queue, debounce | threadId, messageId | | `message-superseded` | debounce | threadId, droppedId | | `message-debouncing` | debounce | threadId, messageId, debounceMs | | `message-debounce-reset` | debounce | threadId, messageId | ## Backward Compatibility - Default remains `'drop'` — zero breaking changes for existing users - `onLockConflict` continues to work but is marked `@deprecated` - Handler signatures are backward-compatible (new `context` param is optional) - Deduplication always runs regardless of strategy ## Files Changed - `packages/chat/src/types.ts` — new types, updated handler signatures - `packages/chat/src/chat.ts` — strategy routing, drain/debounce loops - `packages/chat/src/index.ts` — export new types - `packages/chat/src/mock-adapter.ts` — queue methods for test mock - `packages/state-memory/src/index.ts` — in-memory queue - `packages/state-redis/src/index.ts` — Redis queue (Lua) - `packages/state-ioredis/src/index.ts` — ioredis queue (Lua) - `packages/state-pg/src/index.ts` — Postgres queue table - `packages/chat/src/chat.test.ts` — tests for queue, debounce, concurrent Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> * test: comprehensive test coverage for concurrency strategies and queue methods Add tests across all state adapters and the Chat class: **MemoryStateAdapter** (8 new tests): - enqueue/dequeue single entry - dequeue from empty queue returns null - dequeue from nonexistent thread returns null - queueDepth returns 0 for empty queue - FIFO ordering across multiple entries - maxSize trimming (keeps newest) - maxSize=1 debounce behavior (last-write-wins) - queue isolation by thread - queue cleared on disconnect **PostgresStateAdapter** (8 new tests): - INSERT query for enqueue - overflow trimming query - depth return value - parsed entry from dequeue - null from empty dequeue - atomic DELETE-RETURNING for dequeue - queueDepth return value - zero depth for empty queue **RedisStateAdapter / IoRedisStateAdapter** (3+3 existence checks): - enqueue, dequeue, queueDepth method existence **Chat concurrency** (5 new tests): - drop-newest policy when queue is full - drop-oldest policy evicts oldest entries - expired entries skipped during drain - onNewMessage pattern handlers receive context - onSubscribedMessage handlers receive skipped context Total new tests: 27 (780 chat + 33 memory + 59 pg) Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com> * Address feedback * Support a channel locking strategy, make it default for WhatsApp and Telegram * docs: fix typo "Committment" → "Commitment" (#274) Co-authored-by: Arif Kobel <arif.kobel@phorax.com> * Add webhook verification to GChat (#287) - Issues a warning if required env vars are not present (also for telegram) - Makes telegram use a time-safe verifier * Make adapters depend on `chat` as a real dep (#289) Without this, changeset will make any dep change a major change * Version Packages (#290) Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com> * Fix serialization --------- Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com> Co-authored-by: Arif Kobel <102538661+ArifKobel@users.noreply.github.com> Co-authored-by: Arif Kobel <arif.kobel@phorax.com> Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
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Summary
Fixed typo in the contributing guide: "Committment" → "Commitment"
Type
Documentation fix
Files changed
apps/docs/content/docs/contributing/building.mdx