Class MCollective::Client
In: lib/mcollective/client.rb
Parent: Object

Helpers for writing clients that can talk to agents, do discovery and so forth

Methods

Attributes

discoverer  [RW] 
options  [RW] 
stats  [RW] 

Public Class methods

[Source]

    # File lib/mcollective/client.rb, line 6
 6:     def initialize(configfile)
 7:       @config = Config.instance
 8:       @config.loadconfig(configfile) unless @config.configured
 9: 
10:       @connection = PluginManager["connector_plugin"]
11:       @security = PluginManager["security_plugin"]
12: 
13:       @security.initiated_by = :client
14:       @options = nil
15:       @subscriptions = {}
16: 
17:       @discoverer = Discovery.new(self)
18:       @connection.connect
19:     end

Public Instance methods

Returns the configured main collective if no specific collective is specified as options

[Source]

    # File lib/mcollective/client.rb, line 23
23:     def collective
24:       if @options[:collective].nil?
25:         @config.main_collective
26:       else
27:         @options[:collective]
28:       end
29:     end

Disconnects cleanly from the middleware

[Source]

    # File lib/mcollective/client.rb, line 32
32:     def disconnect
33:       Log.debug("Disconnecting from the middleware")
34:       @connection.disconnect
35:     end

Performs a discovery of nodes matching the filter passed returns an array of nodes

An integer limit can be supplied this will have the effect of the discovery being cancelled soon as it reached the requested limit of hosts

[Source]

     # File lib/mcollective/client.rb, line 115
115:     def discover(filter, timeout, limit=0)
116:       raise "Limit has to be an integer" unless limit.is_a?(Fixnum)
117: 
118:       compount_timeout = timeout_for_compound_filter(@options[:filter]["compound"])
119:       timeout = timeout + compount_timeout
120: 
121:       discovered = @discoverer.discover(filter, timeout, limit)
122:     end

[Source]

     # File lib/mcollective/client.rb, line 181
181:     def discovered_req(body, agent, options=false)
182:       raise "Client#discovered_req has been removed, please port your agent and client to the SimpleRPC framework"
183:     end

Prints out the stats returns from req and discovered_req in a nice way

[Source]

     # File lib/mcollective/client.rb, line 207
207:     def display_stats(stats, options=false, caption="stomp call summary")
208:       options = @options unless options
209: 
210:       if options[:verbose]
211:         puts("\n---- #{caption} ----")
212: 
213:         if stats[:discovered]
214:           puts("           Nodes: #{stats[:discovered]} / #{stats[:responses]}")
215:         else
216:           puts("           Nodes: #{stats[:responses]}")
217:         end
218: 
219:         printf("      Start Time: %s\n", Time.at(stats[:starttime]))
220:         printf("  Discovery Time: %.2fms\n", stats[:discoverytime] * 1000)
221:         printf("      Agent Time: %.2fms\n", stats[:blocktime] * 1000)
222:         printf("      Total Time: %.2fms\n", stats[:totaltime] * 1000)
223: 
224:       else
225:         if stats[:discovered]
226:           printf("\nFinished processing %d / %d hosts in %.2f ms\n\n", stats[:responses], stats[:discovered], stats[:blocktime] * 1000)
227:         else
228:           printf("\nFinished processing %d hosts in %.2f ms\n\n", stats[:responses], stats[:blocktime] * 1000)
229:         end
230:       end
231: 
232:       if stats[:noresponsefrom].size > 0
233:         puts("\nNo response from:\n")
234: 
235:         stats[:noresponsefrom].each do |c|
236:           puts if c % 4 == 1
237:           printf("%30s", c)
238:         end
239: 
240:         puts
241:       end
242:     end

Blocking call that waits for ever for a message to arrive.

If you give it a requestid this means you‘ve previously send a request with that ID and now you just want replies that matches that id, in that case the current connection will just ignore all messages not directed at it and keep waiting for more till it finds a matching message.

[Source]

     # File lib/mcollective/client.rb, line 85
 85:     def receive(requestid = nil)
 86:       reply = nil
 87: 
 88:       begin
 89:         reply = @connection.receive
 90:         reply.type = :reply
 91:         reply.expected_msgid = requestid
 92: 
 93:         reply.decode!
 94: 
 95:         reply.payload[:senderid] = Digest::MD5.hexdigest(reply.payload[:senderid]) if ENV.include?("MCOLLECTIVE_ANON")
 96: 
 97:         raise(MsgDoesNotMatchRequestID, "Message reqid #{requestid} does not match our reqid #{reply.requestid}") unless reply.requestid == requestid
 98:       rescue SecurityValidationFailed => e
 99:         Log.warn("Ignoring a message that did not pass security validations")
100:         retry
101:       rescue MsgDoesNotMatchRequestID => e
102:         Log.debug("Ignoring a message for some other client")
103:         retry
104:       end
105: 
106:       reply
107:     end

Send a request, performs the passed block for each response

times = req("status", "mcollectived", options, client) {|resp|

  pp resp

}

It returns a hash of times and timeouts for discovery and total run is taken from the options hash which in turn is generally built using MCollective::Optionparser

[Source]

     # File lib/mcollective/client.rb, line 132
132:     def req(body, agent=nil, options=false, waitfor=0)
133:       if body.is_a?(Message)
134:         agent = body.agent
135:         options = body.options
136:         waitfor = body.discovered_hosts.size || 0
137:       end
138: 
139:       stat = {:starttime => Time.now.to_f, :discoverytime => 0, :blocktime => 0, :totaltime => 0}
140: 
141:       options = @options unless options
142: 
143:       compount_timeout = timeout_for_compound_filter(options[:filter]["compound"])
144:       timeout = options[:timeout] + compount_timeout
145: 
146:       STDOUT.sync = true
147: 
148:       hosts_responded = 0
149:       reqid = nil
150: 
151:       begin
152:         Timeout.timeout(timeout) do
153:           reqid = sendreq(body, agent, options[:filter])
154: 
155:           loop do
156:             resp = receive(reqid)
157: 
158:             hosts_responded += 1
159: 
160:             yield(resp.payload)
161: 
162:             break if (waitfor != 0 && hosts_responded >= waitfor)
163:           end
164:         end
165:       rescue Interrupt => e
166:       rescue Timeout::Error => e
167:       ensure
168:         unsubscribe(agent, :reply)
169:       end
170: 
171:       stat[:totaltime] = Time.now.to_f - stat[:starttime]
172:       stat[:blocktime] = stat[:totaltime] - stat[:discoverytime]
173:       stat[:responses] = hosts_responded
174:       stat[:noresponsefrom] = []
175:       stat[:requestid] = reqid
176: 
177:       @stats = stat
178:       return stat
179:     end

Sends a request and returns the generated request id, doesn‘t wait for responses and doesn‘t execute any passed in code blocks for responses

[Source]

    # File lib/mcollective/client.rb, line 39
39:     def sendreq(msg, agent, filter = {})
40:       if msg.is_a?(Message)
41:         request = msg
42:         agent = request.agent
43:       else
44:         ttl = @options[:ttl] || @config.ttl
45:         request = Message.new(msg, nil, {:agent => agent, :type => :request, :collective => collective, :filter => filter, :ttl => ttl})
46:         request.reply_to = @options[:reply_to] if @options[:reply_to]
47:       end
48: 
49:       request.encode!
50: 
51:       Log.debug("Sending request #{request.requestid} to the #{request.agent} agent with ttl #{request.ttl} in collective #{request.collective}")
52: 
53:       subscribe(agent, :reply) unless request.reply_to
54: 
55:       request.publish
56: 
57:       request.requestid
58:     end

[Source]

    # File lib/mcollective/client.rb, line 60
60:     def subscribe(agent, type)
61:       unless @subscriptions.include?(agent)
62:         subscription = Util.make_subscriptions(agent, type, collective)
63:         Log.debug("Subscribing to #{type} target for agent #{agent}")
64: 
65:         Util.subscribe(subscription)
66:         @subscriptions[agent] = 1
67:       end
68:     end

if a compound filter is specified and it has any function then we read the DDL for each of those plugins and sum up the timeout declared in the DDL

[Source]

     # File lib/mcollective/client.rb, line 188
188:     def timeout_for_compound_filter(compound_filter)
189:       return 0 if compound_filter.nil? || compound_filter.empty?
190: 
191:       timeout = 0
192: 
193:       compound_filter.each do |filter|
194:         filter.each do |statement|
195:           if statement["fstatement"]
196:             pluginname = Data.pluginname(statement["fstatement"]["name"])
197:             ddl = DDL.new(pluginname, :data)
198:             timeout += ddl.meta[:timeout]
199:           end
200:         end
201:       end
202: 
203:       timeout
204:     end

[Source]

    # File lib/mcollective/client.rb, line 70
70:     def unsubscribe(agent, type)
71:       if @subscriptions.include?(agent)
72:         subscription = Util.make_subscriptions(agent, type, collective)
73:         Log.debug("Unsubscribing #{type} target for #{agent}")
74: 
75:         Util.unsubscribe(subscription)
76:         @subscriptions.delete(agent)
77:       end
78:     end

[Validate]