4 # :title: Alias plugin for rbot
6 # Author:: Yaohan Chen <yaohan.chen@gmail.com>
7 # Copyright:: (C) 2007 Yaohan Chen
10 # This plugin allows defining aliases for rbot commands. Aliases are like normal rbot
11 # commands and can take parameters. When called, they will be substituted into an
12 # exisitng rbot command and that is run.
15 # < alias googlerbot *terms => google site:linuxbrit.co.uk/rbot/ <terms>
17 # < googlerbot plugins
18 # > Results for site:linuxbrit.co.uk/rbot/ plugins: ....
21 # By default, only the owner can define and remove aliases, while everyone else can
22 # use and view them. When a command is executed with an alias, it's mapped normally with
23 # the alias user appearing to attempt to execute the command. Therefore it should be not
24 # possible to use aliases to circumvent permission sets. Care should be taken when
25 # defining aliases, due to these concerns:
26 # * Defined aliases can potentially override other plugins' maps, if this plugin is
28 # * Aliases can cause infinite recursion of aliases and/or commands. The plugin attempts
29 # to detect and stop this, but a few recursive calls can still cause spamming
33 class AliasPlugin < Plugin
34 # an exception raised when loading or getting input of invalid alias definitions
35 class AliasDefinitionError < ArgumentError
38 MAX_RECURSION_DEPTH = 10
42 @data_path = "#{@bot.botclass}/alias/"
43 @data_file = "#{@data_path}/aliases.yaml"
44 # hash of alias => command entries
45 @aliases = if File.exist?(@data_file)
46 YAML.load_file(@data_file)
50 @aliases.each_pair do |a, c|
53 rescue AliasDefinitionError
54 warning _("Invalid alias entry %{alias} : %{command} in %{filename}: %{reason}") %
55 {:alias => a, :command => c, :filename => @data_file, :reason => $1}
61 Dir.mkdir(@data_path) unless File.exist?(@data_path)
62 File.open(@data_file, 'w') {|f| f.write @aliases.to_yaml}
65 def cmd_add(m, params)
67 add_alias(params[:text].to_s, params[:command].to_s)
69 rescue AliasDefinitionError
70 m.reply _('The definition you provided is invalid: %{reason}') % {:reason => $!}
74 def cmd_remove(m, params)
75 text = params[:text].to_s
76 if @aliases.has_key?(text)
78 # TODO when rbot supports it, remove the mapping corresponding to the alias
81 m.reply _('No such alias is defined')
85 def cmd_list(m, params)
87 m.reply _('No aliases defined')
89 m.reply @aliases.map {|a, c| "#{a} => #{c}"}.join(' | ')
93 def cmd_whatis(m, params)
94 text = params[:text].to_s
95 if @aliases.has_key?(text)
96 m.reply _('Alias of %{command}') % {:command => @aliases[text]}
98 m.reply _('No such alias is defined')
102 def add_alias(text, command)
103 # each alias is implemented by adding a message map, whose handler creates a message
104 # containing the aliased command
106 command.grep(/<(\w+)>/) {$1}.all? {|s| text =~ /(?:^|\s)[:*]#{s}(?:\s|$)/ } or
107 raise AliasDefinitionError.new(_('Not all substitutions in command text have matching arguments in alias text'))
109 @aliases[text] = command
110 map text, :action => :"alias_handle<#{text}>", :auth_path => 'run'
113 def respond_to?(name, include_private=false)
114 name.to_s =~ /\Aalias_handle<.+>\Z/ || super
117 def method_missing(name, *args, &block)
118 if name.to_s =~ /\Aalias_handle<(.+)>\Z/
120 # messages created by alias handler will have a depth method, which returns the
121 # depth of "recursion" caused by the message
122 current_depth = if m.respond_to?(:depth) then m.depth else 0 end
123 if current_depth > MAX_RECURSION_DEPTH
124 m.reply _('The alias seems to have caused infinite recursion. Please examine your alias definitions')
128 command = @aliases[$1]
130 # create a fake message containing the intended command
131 new_msg = PrivMessage.new(@bot, m.server, m.server.user(m.source), m.target,
132 command.gsub(/<(\w+)>/) {|arg| params[:"#{$1}"].to_s})
133 # tag incremented depth on the message
136 end.send(:define_method, :depth) {current_depth + 1}
138 @bot.plugins.privmsg(new_msg)
140 m.reply _("Error handling the alias, the command is not defined")
143 super(name, *args, &block)
147 def help(plugin, topic='')
150 _('Create and use aliases for commands. Topics: create, commands')
152 _('"alias <text> => <command>" => add text as an alias of command. Text can contain placeholders marked with : or * for :words and *multiword arguments. The command can contain placeholders enclosed with < > which will be substituded with argument values. For example: alias googlerbot *terms => google site:linuxbrit.co.uk/rbot/ <terms>')
154 _('alias list => list defined aliases | alias whatis <alias> => show definition of the alias | alias remove <alias> => remove defined alias | see the "create" topic about adding aliases')
159 plugin = AliasPlugin.new
160 plugin.default_auth('edit', false)
161 plugin.default_auth('run', true)
162 plugin.default_auth('list', true)
164 plugin.map 'alias list',
165 :action => :cmd_list,
167 plugin.map 'alias whatis *text',
168 :action => :cmd_whatis,
170 plugin.map 'alias remove *text',
171 :action => :cmd_remove,
173 plugin.map 'alias rm *text',
174 :action => :cmd_remove,
176 plugin.map 'alias *text => *command',