# Changelog All notable changes to this project are documented here. The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/), and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). ## [0.2.2] - 2026-07-09 Robustness release: no user action, handler return value, or malformed Slack frame can take a transport down. ### Fixed - **A `view_submission` handler can no longer take down the transport.** When a handler returned an `{:ack, map}` whose payload wasn't JSON-encodable (e.g. it held a tuple), encoding the ACK frame raised inside the transport process — on Socket Mode this crashed the connection and the supervisor's restart re-read the same envelope, producing a crash-reconnect loop. The payload is now checked for encodability in `Slink.Dispatcher.ack_result/3`; a non-encodable one is logged and degrades to `%{}` (closing the modal), like a handler crash already does. - **A malformed Slack frame can no longer crash the Socket Mode connection.** `Slink.Event` parsing and accessors used `get_in/2`, which raises when a value Slack normally nests as a map (a `channel`, `view`, `item`, or the envelope `payload` itself) arrives as a string, list, or null. Since `event_id/1` and event construction run in the socket process, that raise dropped the connection. All parsing and accessors are now total — a wrong-shaped payload yields `nil`/empty defaults instead of raising — and the socket wraps per-message handling as a final backstop. - **A bad reply body no longer crashes a channel's rate-limit worker.** If a handler's reply carried a body the Web API client couldn't encode, the raise killed the per-channel `Slink.Rate.Channel` worker and dropped everything else queued for that channel. The send is now wrapped so a raising call is logged and draining continues, and `Slink.Rate` tolerates a worker that fails to start rather than crashing the caller. - **The Events API plug no longer 500s on a form body with invalid percent-encoding** — `URI.decode_query/1` raising now degrades to an empty payload. ## [0.2.1] - 2026-07-09 ### Fixed - **`reply/3` to a reaction event no longer crashes.** `reaction_added` / `reaction_removed` nest their target under `payload["item"]`, so `Event.channel/1`, `ts/1` now read it there — previously a reply to a reaction raised `ArgumentError` (no channel) and `working/3` was a no-op. ### Changed - **`Event.command/1` unwraps Slack link markup to plain text.** A linkified address (``) now comes through as the bare `a@b.com`, and `<@U1|alice>` / `<#C1|general>` / `` reduce to their name/url — so the addressed text reads as a human typed it. A bare `<@U1>` (e.g. the bot's own mention) still drops out. ## [0.2.0] - 2026-07-09 ### Added - **Slash commands, end to end.** Both transports now decode slash-command payloads (`application/x-www-form-urlencoded` over HTTP). `reply/3` routes by event kind — a channel post for messages and interactions, or the `response_url` for a slash command (`to: :ephemeral` default, or `:channel`) — and raises clearly when an event has no channel to reply to (e.g. a `view_submission`). New `Slink.Event` accessors: `command_name/1`, `response_url/1`, `trigger_id/1`. - **Interactivity & modals.** Interactions are routed on their inner type (`:block_actions`, `:view_submission`, `:shortcut`, …). A `view_submission` handler may return `{:ack, map}` to control the modal (validation errors, update, push) — it runs synchronously so Slack gets the response in time. New helper `open_modal/2` (imported by `use Slink`) and `Slink.API.open_view/3`, `update_view/3`, `push_view/3`, `publish_view/3` (App Home). New `Slink.Event` accessors: `actions/1`, `action_id/1`, `action_value/1`, `callback_id/1`, `view/1`, `view_values/1`. - **Event deduplication** (`Slink.Dedup`). Slack's retried deliveries (same `event_id`) dispatch only once. On by default; `config :slink, :dedup, false` to disable, `:dedup_ttl_ms` to tune. New `Slink.Event.event_id/1`, `retry?/1`, `retry_attempt/1`. - **Wider Web API surface** (`Slink.API`): `update_message/5`, `delete_message/3`, `post_ephemeral/5`, `get_permalink/3`, `user_info/2`, and `respond/2` (post to a `response_url`). `call/3` now retries HTTP `429`s, honouring `Retry-After`. ## [0.1.0] - 2026-07-08 Initial release. ### Added - **One event-handling contract, two transports.** Write a bot once against the `Slink` behaviour and run it over either transport unchanged. - `Slink.SocketMode` — dials out to Slack over a WebSocket (`Mint.WebSocket`), no public endpoint required. Opens the connection via `apps.connections.open`, auto-reconnects, and optionally auto-joins channels on boot (`:join`). - `Slink.EventsApi.Plug` — a `Plug` for Slack's HTTP event callbacks. Mount it in a Plug/Phoenix router or run it standalone with Bandit. - **Request hardening (Events API):** HMAC-SHA256 signature verification against the raw body, constant-time comparison, timestamp-freshness (replay) window, request-body size cap, and automatic `url_verification` handshake. - **Normalised events.** `Slink.Event` collapses Socket Mode envelopes and HTTP payloads into one shape; both transports acknowledge to Slack *before* your handler runs and dispatch off-process, so a slow handler never blows Slack's ~3s ACK window. - **Handler helpers** (imported by `use Slink`): `send_message/3,4`, `reply/2,3`, `working/2,3`, and `in_thread?/1`. - **Per-channel outbound rate limiting** (`Slink.Rate`) to stay within Slack's ~1 message/sec/channel limit. Tunable via `config :slink, :rate_interval_ms`. - **Web API client** (`Slink.API`) built on `Req`. - `Slink.enabled?/1` to conditionally start a bot from config. - A shippable app manifest (`manifest.json`) and a runnable `Slink.ExampleBot`. [0.2.2]: https://github.com/wkirschbaum/slink/compare/v0.2.1...v0.2.2 [0.2.1]: https://github.com/wkirschbaum/slink/compare/v0.2.0...v0.2.1 [0.2.0]: https://github.com/wkirschbaum/slink/compare/v0.1.0...v0.2.0 [0.1.0]: https://github.com/wkirschbaum/slink/releases/tag/v0.1.0