slack-rtm

A Clojure library to interact with the Slack Real Time Messaging API. It's powered by clj-slack and core.async.

Usage

Include [slack-rtm "0.1.6"] in your dependencies. Get a Slack token (it can be a bot token too). Then:

(use 'slack-rtm.core)

;; connect to the Real Time Messaging API
;; you can also use (start "your-token") see difference here: https://api.slack.com/rtm
(def rtm-conn (connect "your-token"))

;; rtm-conn is a map with publications and channels that
;; allows you to receive and send data to and from Slack.

;; :events-publication allows you to listen for slack events
(def events-publication (:events-publication rtm-conn))

;; let's listen for events of type :pong
(def pong-receiver #(println "got this:" %))
(sub-to-event events-publication :pong pong-receiver)

;; send events to Slack by getting the dispatcher channel
(def dispatcher (:dispatcher rtm-conn))
(send-event dispatcher {:type "ping"})

;; at this point pong-receiver should have been called with a pong response

The map returned by connect has four items:

• :start is map containing the response from the Slack API rtm.start method, which contains data about the current state of the team:

• :events-publication is a core.async publication that you can use to subscribe to the different kind of slack event types. You can use core.async's sub method using as topic the string version of the event type (e.g. "message", "im_open", etc.). Or better yet, use the sub-to-event function that allows you to subscribe both a core.async channel or an unary function; it also allows you to subscribe using keywords (e.g. :message, :im_open, etc.).

• :dispatcher is a core.async channel you can use to send events to slack. You can use core.async primitive methods (>!!, >!, put!), or better yet use send-event which automatically adds an :id to the map if none is present.

• :websocket-publication is a core.async publication that allows you to subscribe to raw WebSocket callbacks. It support the following topics: :on-connect, :on-receive, :on-binary, :on-close, :on-error. Refer to stylefruits/gniazdo for information on these.

Hook subscriptions before connecting

Using (connect "token") will connect right away, which means you can miss events (like the hello event) by the time you subscribe. You can subscribe to any event before the connection has been performed by specifying a list of :topics channel-or-function pairs to connect like this:

(connect "token"
         :hello #(prn %)
         :on-close (fn [{:keys [status reason]}] (prn status reason)))

Running Tests

Export a TOKEN environment variable with your Slack token or create file .slack.clj to your home directory with following content:

{:slack-rtm "your-legacy-token-here"}

You can get yours from https://api.slack.com/custom-integrations/legacy-tokens.

Run the test suite:

lein test

Wait until the connection is closed

If you are starting the client from a -main function then you likely want to wait until the connection is closed before exiting from the function. (All the threads are started in the background and do not prevent main and thus the application from exiting.) You might do something like this:

(defn -main []
  (let [{:keys [events-publication dispatcher start]} (connect)]
    ; ...
    (let [c (sub-to-event events-publication :message #(msg-receiver dispatcher %))]
      (loop []
        (a/<!! c)
        (recur)))))

Explanation: sub-to-event returns a channel that gets closed when the connection is closed. (You could also use go-loop or listen for the :on-close event ...)

License

Distributed under the WTFPL.