Class: SlackBotServer::Server

Inherits:
Object
  • Object
show all
Includes:
Logging
Defined in:
lib/slack_bot_server/server.rb

Overview

Implements a server for running multiple Slack bots. Bots can be dynamically added and removed, and can be interacted with from external services (like your application).

To use this, you should create a script to run along side your application. A simple example:

#!/usr/bin/env ruby

require 'slack_bot_server'
require 'slack_bot_server/redis_queue'
require 'slack_bot_server/simple_bot'

# Use a Redis-based queue to add/remove bots and to trigger
# bot messages to be sent
queue = SlackBotServer::RedisQueue.new

# Create a new server using that queue
server = SlackBotServer::Server.new(queue: queue)

# How your application-specific should be created when the server
# is told about a new slack api token to connect with
server.on_add do |token|
  # Return a new bot instance to the server. `SimpleBot` is a provided
  # example bot with some very simple behaviour.
  SlackBotServer::SimpleBot.new(token: token)
end

# Start the server. This method blocks, and will not return until
# the server is killed.
server.start

The key features are:

  • creating a queue as a conduit for commands from your app

  • creating an instance of Server with that queue

  • defining an #on_add block, which is run whenever you need to start a new bot. This block contains the custom code relevant to your particular service, most typically the instantiation of a bot class that implements the logic you want

  • calling #start, to actually run the server and start listening for commands from the queue and connecting bots to Slack itself

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Logging

#debug, #log, #log_error, #log_string

Constructor Details

#initialize(queue: SlackBotServer::LocalQueue.new) ⇒ Server

Creates a new SlackBotServer::Server

Parameters:

  • queue (Object) (defaults to: SlackBotServer::LocalQueue.new) —

    anything that implements the queue protocol (e.g. #push and #pop)



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# File 'lib/slack_bot_server/server.rb', line 59

def initialize(queue: SlackBotServer::LocalQueue.new)
  @queue = queue
  @bots = {}
  @add_proc = -> (token) { SlackBotServer::SimpleBot.new(token: token) }
  @running = false
end

Instance Attribute Details

#queue ⇒ Object (readonly)

Returns the value of attribute queue.



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# File 'lib/slack_bot_server/server.rb', line 54

def queue
  @queue
end

Instance Method Details

#add_bot(*args) ⇒ Object

Adds a bot to this server Calls the block given to #on_add with the arguments given. The block should yield a bot, typically a subclass of Bot.

See Also:



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# File 'lib/slack_bot_server/server.rb', line 109

def add_bot(*args)
  bot = @add_proc.call(*args)
  if bot.respond_to?(:start) && !bot(bot.key)
    log "adding bot #{bot}"
    @bots[bot.key] = bot
    bot.start if @running
  end
rescue => e
  log_error(e)
end

#bot(key) ⇒ Object

Find a bot added to this server. Returns nil if no bot was found

Parameters:

  • key (String) —

    the key of the bot we’re looking for

Returns:

  • Bot



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# File 'lib/slack_bot_server/server.rb', line 101

def bot(key)
  @bots[key]
end

#on_add(&block) ⇒ Object

Define the block which should be called when the #add_bot method is called, or the add_bot message is sent via a queue. This block should return a bot (which responds to start), in which case it will be added and started. If anything else is returned, it will be ignored.



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# File 'lib/slack_bot_server/server.rb', line 70

def on_add(&block)
  @add_proc = block
end

#remove_bot(key) ⇒ Object

Stops and removes a bot from the server

Parameters:

  • key (String) —

    the key of the bot to remove

See Also:



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# File 'lib/slack_bot_server/server.rb', line 123

def remove_bot(key)
  if (bot = bot(key))
    bot.stop
    @bots.delete(key)
  end
rescue => e
  log_error(e)
end

#start ⇒ Object

Starts the server. This method will not return; call it at the end of your server script. It will start all bots it knows about (i.e. bots added via #add_bot before the server was started), and then listen for new instructions.

See Also:



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# File 'lib/slack_bot_server/server.rb', line 79

def start
  EM.run do
    @running = true
    @bots.each do |key, bot|
      begin
        bot.start
      rescue => e
        log_error(e)
      end
    end
    listen_for_instructions if queue
  end
end

#start_in_background ⇒ Object

Starts the server in the background, via a Thread



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# File 'lib/slack_bot_server/server.rb', line 94

def start_in_background
  Thread.start { start }
end