Class MCollective::RPC::Helpers
In: lib/mcollective/rpc/helpers.rb
Parent: Object

Various utilities for the RPC system

Methods

Public Class methods

Add SimpleRPC common options

[Source]

     # File lib/mcollective/rpc/helpers.rb, line 250
250:       def self.add_simplerpc_options(parser, options)
251:         parser.separator ""
252: 
253:         # add SimpleRPC specific options to all clients that use our library
254:         parser.on('--np', '--no-progress', 'Do not show the progress bar') do |v|
255:           options[:progress_bar] = false
256:         end
257: 
258:         parser.on('--one', '-1', 'Send request to only one discovered nodes') do |v|
259:           options[:mcollective_limit_targets] = 1
260:         end
261: 
262:         parser.on('--batch SIZE', Integer, 'Do requests in batches') do |v|
263:           options[:batch_size] = v
264:         end
265: 
266:         parser.on('--batch-sleep SECONDS', Float, 'Sleep time between batches') do |v|
267:           options[:batch_sleep_time] = v
268:         end
269: 
270:         parser.on('--limit-seed NUMBER', Integer, 'Seed value for deterministic random batching') do |v|
271:           options[:limit_seed] = v
272:         end
273: 
274:         parser.on('--limit-nodes COUNT', '--ln', '--limit', 'Send request to only a subset of nodes, can be a percentage') do |v|
275:           raise "Invalid limit specified: #{v} valid limits are /^\d+%*$/" unless v =~ /^\d+%*$/
276: 
277:           if v =~ /^\d+$/
278:             options[:mcollective_limit_targets] = v.to_i
279:           else
280:             options[:mcollective_limit_targets] = v
281:           end
282:         end
283: 
284:         parser.on('--json', '-j', 'Produce JSON output') do |v|
285:           options[:progress_bar] = false
286:           options[:output_format] = :json
287:         end
288: 
289:         parser.on('--display MODE', 'Influence how results are displayed. One of ok, all or failed') do |v|
290:           if v == "all"
291:             options[:force_display_mode] = :always
292:           else
293:             options[:force_display_mode] = v.intern
294:           end
295: 
296:           raise "--display has to be one of 'ok', 'all' or 'failed'" unless [:ok, :failed, :always].include?(options[:force_display_mode])
297:         end
298:       end

Given an array of something, make sure each is a string chomp off any new lines and return just the array of hosts

[Source]

    # File lib/mcollective/rpc/helpers.rb, line 29
29:       def self.extract_hosts_from_array(hosts)
30:         [hosts].flatten.map do |host|
31:           raise "#{host} should be a string" unless host.is_a?(String)
32:           host.chomp
33:         end
34:       end

Parse JSON output as produced by printrpc and extract the "sender" of each rpc response

The simplist valid JSON based data would be:

[

 {"sender" => "example.com"},
 {"sender" => "another.com"}

]

[Source]

    # File lib/mcollective/rpc/helpers.rb, line 14
14:       def self.extract_hosts_from_json(json)
15:         hosts = JSON.parse(json)
16: 
17:         raise "JSON hosts list is not an array" unless hosts.is_a?(Array)
18: 
19:         hosts.map do |host|
20:           raise "JSON host list is not an array of Hashes" unless host.is_a?(Hash)
21:           raise "JSON host list does not have senders in it" unless host.include?("sender")
22: 
23:           host["sender"]
24:         end.uniq
25:       end

Backward compatible display block for results without a DDL

[Source]

     # File lib/mcollective/rpc/helpers.rb, line 198
198:       def self.old_rpcresults(result, flags = {})
199:         result_text = ""
200: 
201:         if flags[:flatten]
202:           result.each do |r|
203:             if r[:statuscode] <= 1
204:               data = r[:data]
205: 
206:               unless data.is_a?(String)
207:                 result_text << data.pretty_inspect
208:               else
209:                 result_text << data
210:               end
211:             else
212:               result_text << r.pretty_inspect
213:             end
214:           end
215: 
216:           result_text << ""
217:         else
218:           [result].flatten.each do |r|
219: 
220:             if flags[:verbose]
221:               result_text << "%-40s: %s\n" % [r[:sender], r[:statusmsg]]
222: 
223:               if r[:statuscode] <= 1
224:                 r[:data].pretty_inspect.split("\n").each {|m| result_text += "    #{m}"}
225:                 result_text << "\n\n"
226:               elsif r[:statuscode] == 2
227:                 # dont print anything, no useful data to display
228:                 # past what was already shown
229:               elsif r[:statuscode] == 3
230:                 # dont print anything, no useful data to display
231:                 # past what was already shown
232:               elsif r[:statuscode] == 4
233:                 # dont print anything, no useful data to display
234:                 # past what was already shown
235:               else
236:                 result_text << "    #{r[:statusmsg]}"
237:               end
238:             else
239:               unless r[:statuscode] == 0
240:                 result_text << "%-40s %s\n" % [r[:sender], Util.colorize(:red, r[:statusmsg])]
241:               end
242:             end
243:           end
244:         end
245: 
246:         result_text << ""
247:       end

Returns a blob of text representing the results in a standard way

It tries hard to do sane things so you often should not need to write your own display functions

If the agent you are getting results for has a DDL it will use the hints in there to do the right thing specifically it will look at the values of display in the DDL to choose when to show results

If you do not have a DDL you can pass these flags:

   printrpc exim.mailq, :flatten => true
   printrpc exim.mailq, :verbose => true

If you‘ve asked it to flatten the result it will not print sender hostnames, it will just print the result as if it‘s one huge result, handy for things like showing a combined mailq.

[Source]

     # File lib/mcollective/rpc/helpers.rb, line 54
 54:       def self.rpcresults(result, flags = {})
 55:         flags = {:verbose => false, :flatten => false, :format => :console, :force_display_mode => false}.merge(flags)
 56: 
 57:         result_text = ""
 58:         ddl = nil
 59: 
 60:         # if running in verbose mode, just use the old style print
 61:         # no need for all the DDL helpers obfuscating the result
 62:         if flags[:format] == :json
 63:           if STDOUT.tty?
 64:             result_text = JSON.pretty_generate(result)
 65:           else
 66:             result_text = result.to_json
 67:           end
 68:         else
 69:           if flags[:verbose]
 70:             result_text = old_rpcresults(result, flags)
 71:           else
 72:             [result].flatten.each do |r|
 73:               begin
 74:                 ddl ||= DDL.new(r.agent).action_interface(r.action.to_s)
 75: 
 76:                 sender = r[:sender]
 77:                 status = r[:statuscode]
 78:                 message = r[:statusmsg]
 79:                 result = r[:data]
 80: 
 81:                 if flags[:force_display_mode]
 82:                   display = flags[:force_display_mode]
 83:                 else
 84:                   display = ddl[:display]
 85:                 end
 86: 
 87:                 # appand the results only according to what the DDL says
 88:                 case display
 89:                   when :ok
 90:                     if status == 0
 91:                       result_text << text_for_result(sender, status, message, result, ddl)
 92:                     end
 93: 
 94:                   when :failed
 95:                     if status > 0
 96:                       result_text << text_for_result(sender, status, message, result, ddl)
 97:                     end
 98: 
 99:                   when :always
100:                     result_text << text_for_result(sender, status, message, result, ddl)
101: 
102:                   when :flatten
103:                     result_text << text_for_flattened_result(status, result)
104: 
105:                 end
106:               rescue Exception => e
107:                 # no DDL so just do the old style print unchanged for
108:                 # backward compat
109:                 result_text = old_rpcresults(result, flags)
110:               end
111:             end
112:           end
113:         end
114: 
115:         result_text
116:       end

Returns text representing a flattened result of only good data

[Source]

     # File lib/mcollective/rpc/helpers.rb, line 185
185:       def self.text_for_flattened_result(status, result)
186:         result_text = ""
187: 
188:         if status <= 1
189:           unless result.is_a?(String)
190:             result_text << result.pretty_inspect
191:           else
192:             result_text << result
193:           end
194:         end
195:       end

Return text representing a result

[Source]

     # File lib/mcollective/rpc/helpers.rb, line 119
119:       def self.text_for_result(sender, status, msg, result, ddl)
120:         statusses = ["",
121:                      Util.colorize(:red, "Request Aborted"),
122:                      Util.colorize(:yellow, "Unknown Action"),
123:                      Util.colorize(:yellow, "Missing Request Data"),
124:                      Util.colorize(:yellow, "Invalid Request Data"),
125:                      Util.colorize(:red, "Unknown Request Status")]
126: 
127:         result_text = "%-40s %s\n" % [sender, statusses[status]]
128:         result_text << "   %s\n" % [Util.colorize(:yellow, msg)] unless msg == "OK"
129: 
130:         # only print good data, ignore data that results from failure
131:         if [0, 1].include?(status)
132:           if result.is_a?(Hash)
133:             # figure out the lengths of the display as strings, we'll use
134:             # it later to correctly justify the output
135:             lengths = result.keys.map do |k|
136:               begin
137:                 ddl[:output][k][:display_as].size
138:               rescue
139:                 k.to_s.size
140:               end
141:             end
142: 
143:             result.keys.sort_by{|k| k}.each do |k|
144:               # get all the output fields nicely lined up with a
145:               # 3 space front padding
146:               begin
147:                 display_as = ddl[:output][k][:display_as]
148:               rescue
149:                 display_as = k.to_s
150:               end
151: 
152:               display_length = display_as.size
153:               padding = lengths.max - display_length + 3
154:               result_text << " " * padding
155: 
156:               result_text << "#{display_as}:"
157: 
158:               if [String, Numeric].include?(result[k].class)
159:                 lines = result[k].to_s.split("\n")
160: 
161:                 if lines.empty?
162:                   result_text << "\n"
163:                 else
164:                   lines.each_with_index do |line, i|
165:                     i == 0 ? padtxt = " " : padtxt = " " * (padding + display_length + 2)
166: 
167:                     result_text << "#{padtxt}#{line}\n"
168:                   end
169:                 end
170:               else
171:                 padding = " " * (lengths.max + 5)
172:                 result_text << " " << result[k].pretty_inspect.split("\n").join("\n" << padding) << "\n"
173:               end
174:             end
175:           else
176:             result_text << "\n\t" + result.pretty_inspect.split("\n").join("\n\t")
177:           end
178:         end
179: 
180:         result_text << "\n"
181:         result_text
182:       end

[Validate]