Elixir-Slack

This is a work in progress Slack Real Time Messaging API client for Elixir. You’ll need a Slack API token which can be retrieved from the Web API page or by creating a new bot integration.

Usage

Add Slack to your mix.exsapplication and dependencies methods. You’ll also need websocket_client since hex.pm doesn’t install git based dependencies.

def application do
  [applications: [:logger, :slack]]
end

def deps do
  [{:slack, "~> 0.0.5"},
   {:websocket_client, git: "https://github.com/jeremyong/websocket_client"}]
end

Define a module that uses the Slack behaviour and defines the appropriate callback methods.

defmodule SlackRtm do
  use Slack

  def start_link(initial_state) do
    Slack.start_link(__MODULE__, "token_value", initial_state)
  end

  def init(initial_state, slack) do
    IO.puts "Connected as #{slack.me.name}"
    {:ok, initial_state}
  end

  def handle_message({:type, "message", response}, slack, state) do
    state = state ++ [response.text]

    message = "Received #{length(state)} messages so far!"
    Slack.send(message, response.channel, slack)

    {:ok, state}
  end

  def handle_message({:type, type, _response}, _slack, state) do
    {:ok, state}
  end
end

You can send messages to channels using Slack.send which takes the message as the first argument, channel as the second, and the slack argument as the third.

:websocket_client.send({:text, "Hello!"}, slack).

You can also access the properties about the user you’re authenticated as by calling me on the passed in slack state. More details about what’s passed as me can be found on the Slack rtm.start documentation page.

Slack has a lot of message types so it’s a good idea to define a callback like above where unhandled message types don’t crash your application. You can find a list of message types and examples on the RTM API page.

You can find more detailed documentation on the Slack hexdocs page.