Add simple bot example for simpler use-cases

examples/simple_bot.rb

+#!/usr/bin/env ruby
+
+require 'matrix_sdk'
+
+# A filter to simplify syncs
+BOT_FILTER = {
+  presence: { senders: [], types: [] },
+  account_data: { senders: [], types: [] },
+  room: {
+    ephemeral: { senders: [], types: [] },
+    state: {
+      limit: 5,
+      types: ['m.room.*'],
+      lazy_load_members: true
+    },
+    timeline: {
+      limit: 5,
+      types: ['m.room.message']
+    },
+    account_data: { senders: [], types: [] }
+  }
+}.freeze
+
+class MatrixBot
+  def initialize(hs_url, token)
+    @hs_url = hs_url
+    @token = token
+
+    # TODO: Store this between runs for actual usage.
+    @last_batch = nil
+  end
+
+  def run
+    # Join all invited rooms
+    client.on_invite_event.add_handler { |ev| client.join_room(ev[:room_id]) }
+    # Read all message events
+    client.on_event.add_handler('m.room.message') { |ev| on_message(ev) }
+
+    loop do
+      begin
+        client.sync filter: BOT_FILTER
+      rescue MatrixSdk::MatrixError => e
+        puts e
+      end
+    end
+  end
+
+  def on_message(message)
+    room = client.ensure_room message.room_id
+    sender = client.get_user message.sender
+
+    return unless message.content[:body] == '!pingr'
+
+    puts "[#{Time.now.strftime '%H:%M'}] <#{sender.id} in #{room.id}> #{message.content[:body]}"
+
+    origin_ts = Time.at(message[:origin_server_ts] / 1000.0)
+    diff = Time.now - origin_ts
+
+    room.send_notice("#{sender.user_id}: Pong! (Ping took #{(diff * 1000).to_i}ms)")
+  end
+
+  private
+
+  def client
+    @client ||= MatrixSdk::Client.new @hs_url, access_token: @token, client_cache: :none
+  end
+end
+
+if $PROGRAM_NAME == __FILE__
+  raise "Usage: #{$PROGRAM_NAME} [-d] homeserver_url access_token" unless ARGV.length >= 2
+
+  if ARGV.first == '-d'
+    Thread.abort_on_exception = true
+    MatrixSdk.debug!
+    ARGV.shift
+  end
+
+  bot = MatrixBot.new ARGV[0], ARGV[1]
+  bot.run
+end