Initial work on a DRb-based remote service for rbot. Thanks to halorgium for the idea

1 files changed, 228 insertions, 0 deletions

diff --git a/lib/rbot/core/remote.rb b/lib/rbot/core/remote.rb
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+#-- vim:sw=2:et
+#++
+#
+# :title: Remote service provider for rbot
+#
+# Author:: Giuseppe Bilotta (giuseppe.bilotta@gmail.com)
+# Copyright:: Copyright (c) 2006 Giuseppe Bilotta
+# License:: GPLv2
+#
+# From an idea by halorgium <rbot@spork.in>.
+#
+# TODO client ID and auth
+# TODO Irc::Plugins::RemotePlugin module to be included by plugins that want to
+# provide a remote interface. Such module would define a remote_map() method
+# that would register the plugin to received mapped commands from remote clients.
+# FIXME how should be handle cleanups/rescans? Probably just clear() the
+# RemoteDispatcher template list. Provide a cleanup() method for
+# RemoteDispatcher and think about this.
+
+require 'drb/drb'
+
+module ::Irc
+
+  # A RemoteCommand is similar to a BaiscUserMessage
+  #
+  class RemoteMessage
+    # associated bot
+    attr_reader :bot
+
+    # when the message was received
+    attr_reader :time
+
+    # remote client that originated the message
+    attr_reader :source
+
+    # contents of the message
+    attr_accessor :message
+
+    def initialize(bot, source, message)
+      @bot = bot
+      @source = source
+      @message = message
+      @time = Time.now
+    end
+
+    # The target of a RemoteMessage
+    def target
+      @bot
+    end
+
+    # Remote messages are always 'private'
+    def private?
+      true
+    end
+  end
+
+  class RemoteDispatcher < MessageMapper
+
+    def initialize(bot)
+      super(bot)
+    end
+
+    # We redefine the handle() method from MessageMapper, taking into account
+    # that @parent is a bot, and that we don't handle fallbacks
+    #
+    # TODO this same kind of mechanism could actually be used in MessageMapper
+    # itself to be able to handle the case of multiple plugins having the same
+    # 'first word' ...
+    #
+    def handle(m)
+      return false if @templates.empty?
+      failures = []
+      @templates.each do |tmpl|
+        botmodule = @parent.plugins[tmpl.botmodule]
+        options, failure = tmpl.recognize(m)
+        if options.nil?
+          failures << [tmpl, failure]
+        else
+          action = tmpl.options[:action]
+          unless botmodule.respond_to?(action)
+            failures << [tmpl, "#{botmodule} does not respond to action #{action}"]
+            next
+          end
+          auth = tmpl.options[:full_auth_path]
+          debug "checking auth for #{auth}"
+          if m.bot.auth.allow?(auth, m.source, m.replyto)
+            debug "template match found and auth'd: #{action.inspect} #{options.inspect}"
+            @parent.send(action, m, options)
+            return true
+          end
+          debug "auth failed for #{auth}"
+          # if it's just an auth failure but otherwise the match is good,
+          # don't try any more handlers
+          return false
+        end
+      end
+      failures.each {|f, r|
+        debug "#{f.inspect} => #{r}"
+      }
+      debug "no handler found"
+      return false
+    end
+
+  end
+
+  class IrcBot
+
+    # The Irc::IrcBot::RemoteObject class represents and object that will take care
+    # of interfacing with remote clients
+    #
+    class RemoteObject
+
+      # We don't want this object to be copied clientside, so we make it undumpable
+      include DRbUndumped
+
+      # Initialization is simple
+      def initialize(bot)
+        @bot = bot
+        @dispatcher = RemoteDispatcher.new(@bot)
+      end
+
+      # The delegate method. This is the main method used by remote clients to send
+      # commands to the bot. Most of the time, the method will be called with only
+      # two parameters (authorization code and a String), but we allow more parameters
+      # for future expansions
+      #
+      def delegate(auth, *pars)
+        warn "Ignoring extra parameters" if pars.length > 1
+        cmd = pars.first
+        # TODO implement auth <-> client conversion
+        # We need at least a RemoteBotUser class derived from Irc::Auth::BotUser
+        # and a way to associate the auth info to the appropriate RemoteBotUser class
+        client = auth
+        debug "Trying to dispatch command #{cmd.inspect} authorized by #{auth.inspect}"
+        m = RemoteMessage.new(@bot, client, cmd)
+        @dispatcher.handle(m)
+      end
+    end
+
+    # The bot also manages a single (for the moment) remote object. This method
+    # makes it accessible to the outside world, creating it if necessary.
+    #
+    def remote_object
+      if defined? @remote_object
+        @remote_object
+      else
+        @remote_object = RemoteObject.new(self)
+      end
+    end
+
+  end
+
+end
+
+class RemoteModule < CoreBotModule
+
+  BotConfig.register BotConfigIntegerValue.new('remote.port',
+    :default => 7268, # that's 'rbot'
+    :on_change => Proc.new { |bot, v|
+      stop_service
+      @port = v
+      start_service
+    },
+    :requires_restart => true,
+    :desc => "Port on which the remote interface will be presented")
+
+  BotConfig.register BotConfigStringValue.new('remote.host',
+    :default => '',
+    :on_change => Proc.new { |bot, v|
+      stop_service
+      @host = v
+      start_service
+    },
+    :requires_restart => true,
+    :desc => "Port on which the remote interface will be presented")
+
+  def initialize
+    super
+    @port = @bot.config['remote.port']
+    @host = @bot.config['remote.host']
+    @drb = nil
+    start_service
+  end
+
+  def start_service
+    raise "Remote service provider already running" if @drb
+    @drb = DRb.start_service("druby://#{@host}:#{@port}", @bot.remote_object)
+  end
+
+  def stop_service
+    @drb.stop_service if @drb
+    @drb = nil
+  end
+
+  def cleanup
+    stop_service
+    super
+  end
+
+  def handle_start(m, params)
+    if @drb
+      rep = "remote service provider already running"
+      rep << " on port #{@port}" if m.private?
+    else
+      begin
+        start_service(@port)
+        rep = "remote service provider started"
+        rep << " on port #{@port}" if m.private?
+      rescue
+        rep = "couldn't start remote service provider"
+      end
+    end
+    m.reply rep
+  end
+
+end
+
+remote = RemoteModule.new
+
+remote.map "remote start",
+  :action => 'handle_start',
+  :auth_path => ':manage:'
+
+remote.map "remote stop",
+  :action => 'handle_stop',
+  :auth_path => ':manage:'
+
+remote.default_auth('*', false)