Module MCollective::Util
In: lib/mcollective/util.rb

Some basic utility helper methods useful to clients, agents, runner etc.

Methods

Public Class methods

Picks a config file defaults to ~/.mcollective else /etc/mcollective/client.cfg

[Source]

     # File lib/mcollective/util.rb, line 132
132:         def self.config_file_for_user
133:             # expand_path is pretty lame, it relies on HOME environment
134:             # which isnt't always there so just handling all exceptions
135:             # here as cant find reverting to default
136:             begin
137:                 config = File.expand_path("~/.mcollective")
138: 
139:                 unless File.readable?(config) && File.file?(config)
140:                     config = "/etc/mcollective/client.cfg"
141:                 end
142:             rescue Exception => e
143:                 config = "/etc/mcollective/client.cfg"
144:             end
145: 
146:             return config
147:         end

Creates a standard options hash

[Source]

     # File lib/mcollective/util.rb, line 150
150:         def self.default_options
151:             {:verbose     => false,
152:              :disctimeout => 2,
153:              :timeout     => 5,
154:              :config      => config_file_for_user,
155:              :collective  => nil,
156:              :filter      => empty_filter}
157:         end

Creates an empty filter

[Source]

     # File lib/mcollective/util.rb, line 122
122:         def self.empty_filter
123:             {"fact"     => [],
124:              "cf_class" => [],
125:              "agent"    => [],
126:              "identity" => [],
127:              "compound" => []}
128:         end

Checks if the passed in filter is an empty one

[Source]

     # File lib/mcollective/util.rb, line 117
117:         def self.empty_filter?(filter)
118:             filter == empty_filter || filter == {}
119:         end

[Source]

     # File lib/mcollective/util.rb, line 238
238:         def self.eval_compound_statement(expression)
239:             if expression.values.first =~ /^\//
240:                 return Util.has_cf_class?(expression.values.first)
241:             elsif expression.values.first =~ />=|<=|=|<|>/
242:                 optype = expression.values.first.match(/>=|<=|=|<|>/)
243:                 name, value = expression.values.first.split(optype[0])
244:                 unless value.split("")[0] == "/"
245:                     optype[0] == "=" ? optype = "==" : optype = optype[0]
246:                 else
247:                     optype = "=~"
248:                 end
249: 
250:                 return Util.has_fact?(name,value, optype).to_s
251:             else
252:                 return Util.has_cf_class?(expression.values.first)
253:             end
254:         end

Gets the value of a specific fact, mostly just a duplicate of MCollective::Facts.get_fact but it kind of goes with the other classes here

[Source]

    # File lib/mcollective/util.rb, line 53
53:         def self.get_fact(fact)
54:             Facts.get_fact(fact)
55:         end

Finds out if this MCollective has an agent by the name passed

If the passed name starts with a / it‘s assumed to be regex and will use regex to match

[Source]

    # File lib/mcollective/util.rb, line 8
 8:         def self.has_agent?(agent)
 9:             agent = Regexp.new(agent.gsub("\/", "")) if agent.match("^/")
10: 
11:             if agent.is_a?(Regexp)
12:                 if Agents.agentlist.grep(agent).size > 0
13:                     return true
14:                 else
15:                     return false
16:                 end
17:             else
18:                 return Agents.agentlist.include?(agent)
19:             end
20: 
21:             false
22:         end

Checks if this node has a configuration management class by parsing the a text file with just a list of classes, recipes, roles etc. This is ala the classes.txt from puppet.

If the passed name starts with a / it‘s assumed to be regex and will use regex to match

[Source]

    # File lib/mcollective/util.rb, line 30
30:         def self.has_cf_class?(klass)
31:             klass = Regexp.new(klass.gsub("\/", "")) if klass.match("^/")
32:             cfile = Config.instance.classesfile
33: 
34:             Log.debug("Looking for configuration management classes in #{cfile}")
35: 
36:             begin
37:                 File.readlines(cfile).each do |k|
38:                     if klass.is_a?(Regexp)
39:                         return true if k.chomp.match(klass)
40:                     else
41:                         return true if k.chomp == klass
42:                     end
43:                 end
44:             rescue Exception => e
45:                 Log.warn("Parsing classes file '#{cfile}' failed: #{e.class}: #{e}")
46:             end
47: 
48:             false
49:         end

Compares fact == value,

If the passed value starts with a / it‘s assumed to be regex and will use regex to match

[Source]

    # File lib/mcollective/util.rb, line 61
61:         def self.has_fact?(fact, value, operator)
62: 
63:             Log.debug("Comparing #{fact} #{operator} #{value}")
64:             Log.debug("where :fact = '#{fact}', :operator = '#{operator}', :value = '#{value}'")
65: 
66:             fact = Facts[fact]
67:             return false if fact.nil?
68: 
69:             fact = fact.clone
70: 
71:             if operator == '=~'
72:                 # to maintain backward compat we send the value
73:                 # as /.../ which is what 1.0.x needed.  this strips
74:                 # off the /'s wich is what we need here
75:                 if value =~ /^\/(.+)\/$/
76:                     value = $1
77:                 end
78: 
79:                 return true if fact.match(Regexp.new(value))
80: 
81:             elsif operator == "=="
82:                 return true if fact == value
83: 
84:             elsif ['<=', '>=', '<', '>', '!='].include?(operator)
85:                 # Yuk - need to type cast, but to_i and to_f are overzealous
86:                 if value =~ /^[0-9]+$/ && fact =~ /^[0-9]+$/
87:                     fact = Integer(fact)
88:                     value = Integer(value)
89:                 elsif value =~ /^[0-9]+.[0-9]+$/ && fact =~ /^[0-9]+.[0-9]+$/
90:                     fact = Float(fact)
91:                     value = Float(value)
92:                 end
93: 
94:                 return true if eval("fact #{operator} value")
95:             end
96: 
97:             false
98:         end

Checks if the configured identity matches the one supplied

If the passed name starts with a / it‘s assumed to be regex and will use regex to match

[Source]

     # File lib/mcollective/util.rb, line 104
104:         def self.has_identity?(identity)
105:             identity = Regexp.new(identity.gsub("\/", "")) if identity.match("^/")
106: 
107:             if identity.is_a?(Regexp)
108:                 return Config.instance.identity.match(identity)
109:             else
110:                 return true if Config.instance.identity == identity
111:             end
112: 
113:             false
114:         end

Wrapper around PluginManager.loadclass

[Source]

     # File lib/mcollective/util.rb, line 198
198:         def self.loadclass(klass)
199:             PluginManager.loadclass(klass)
200:         end

[Source]

     # File lib/mcollective/util.rb, line 159
159:         def self.make_subscriptions(agent, type, collective=nil)
160:             config = Config.instance
161: 
162:             raise("Unknown target type #{type}") unless [:broadcast, :directed, :reply].include?(type)
163: 
164:             if collective.nil?
165:                 config.collectives.map do |c|
166:                     {:agent => agent, :type => type, :collective => c}
167:                 end
168:             else
169:                 raise("Unknown collective '#{collective}' known collectives are '#{config.collectives.join ', '}'") unless config.collectives.include?(collective)
170: 
171:                 [{:agent => agent, :type => type, :collective => collective}]
172:             end
173:         end

Parse a fact filter string like foo=bar into the tuple hash thats needed

[Source]

     # File lib/mcollective/util.rb, line 203
203:         def self.parse_fact_string(fact)
204:             if fact =~ /^([^ ]+?)[ ]*=>[ ]*(.+)/
205:                 return {:fact => $1, :value => $2, :operator => '>=' }
206:             elsif fact =~ /^([^ ]+?)[ ]*=<[ ]*(.+)/
207:                 return {:fact => $1, :value => $2, :operator => '<=' }
208:             elsif fact =~ /^([^ ]+?)[ ]*(<=|>=|<|>|!=|==|=~)[ ]*(.+)/
209:                 return {:fact => $1, :value => $3, :operator => $2 }
210:             elsif fact =~ /^(.+?)[ ]*=[ ]*\/(.+)\/$/
211:                 return {:fact => $1, :value => "/#{$2}/", :operator => '=~' }
212:             elsif fact =~ /^([^= ]+?)[ ]*=[ ]*(.+)/
213:                 return {:fact => $1, :value => $2, :operator => '==' }
214:             else
215:                 raise "Could not parse fact #{fact} it does not appear to be in a valid format"
216:             end
217:         end

Escapes a string so it‘s safe to use in system() or backticks

Taken from Shellwords#shellescape since it‘s only in a few ruby versions

[Source]

     # File lib/mcollective/util.rb, line 222
222:         def self.shellescape(str)
223:             return "''" if str.empty?
224: 
225:             str = str.dup
226: 
227:             # Process as a single byte sequence because not all shell
228:             # implementations are multibyte aware.
229:             str.gsub!(/([^A-Za-z0-9_\-.,:\/@\n])/n, "\\\\\\1")
230: 
231:             # A LF cannot be escaped with a backslash because a backslash + LF
232:             # combo is regarded as line continuation and simply ignored.
233:             str.gsub!(/\n/, "'\n'")
234: 
235:             return str
236:         end

Helper to subscribe to a topic on multiple collectives or just one

[Source]

     # File lib/mcollective/util.rb, line 176
176:         def self.subscribe(targets)
177:             connection = PluginManager["connector_plugin"]
178: 
179:             targets = [targets].flatten
180: 
181:             targets.each do |target|
182:                 connection.subscribe(target[:agent], target[:type], target[:collective])
183:             end
184:         end

Helper to unsubscribe to a topic on multiple collectives or just one

[Source]

     # File lib/mcollective/util.rb, line 187
187:         def self.unsubscribe(targets)
188:             connection = PluginManager["connector_plugin"]
189: 
190:             targets = [targets].flatten
191: 
192:             targets.each do |target|
193:                 connection.unsubscribe(target[:agent], target[:type], target[:collective])
194:             end
195:         end

[Validate]