Class | MCollective::RPC::Client |
In: |
lib/mcollective/rpc/client.rb
|
Parent: | Object |
The main component of the Simple RPC client system, this wraps around MCollective::Client and just brings in a lot of convention and standard approached.
agent | [R] | |
batch_mode | [R] | |
batch_size | [R] | |
batch_sleep_time | [R] | |
client | [R] | |
config | [RW] | |
ddl | [R] | |
discovery_method | [R] | |
discovery_options | [R] | |
filter | [RW] | |
limit_method | [R] | |
limit_seed | [R] | |
limit_targets | [R] | |
output_format | [R] | |
progress | [RW] | |
reply_to | [RW] | |
stats | [R] | |
timeout | [RW] | |
ttl | [RW] | |
verbose | [RW] |
Creates a stub for a remote agent, you can pass in an options array in the flags which will then be used else it will just create a default options array with filtering enabled based on the standard command line use.
rpc = RPC::Client.new("rpctest", :configfile => "client.cfg", :options => options)
You typically would not call this directly you‘d use MCollective::RPC#rpcclient instead which is a wrapper around this that can be used as a Mixin
# File lib/mcollective/rpc/client.rb, line 20 20: def initialize(agent, flags = {}) 21: if flags.include?(:options) 22: initial_options = flags[:options] 23: 24: elsif @@initial_options 25: initial_options = Marshal.load(@@initial_options) 26: 27: else 28: oparser = MCollective::Optionparser.new({:verbose => false, :progress_bar => true, :mcollective_limit_targets => false, :batch_size => nil, :batch_sleep_time => 1}, "filter") 29: 30: initial_options = oparser.parse do |parser, opts| 31: if block_given? 32: yield(parser, opts) 33: end 34: 35: Helpers.add_simplerpc_options(parser, opts) 36: end 37: 38: @@initial_options = Marshal.dump(initial_options) 39: end 40: 41: @initial_options = initial_options 42: 43: @config = initial_options[:config] 44: @client = MCollective::Client.new(@config) 45: @client.options = initial_options 46: 47: @stats = Stats.new 48: @agent = agent 49: @timeout = initial_options[:timeout] || 5 50: @verbose = initial_options[:verbose] 51: @filter = initial_options[:filter] || Util.empty_filter 52: @discovered_agents = nil 53: @progress = initial_options[:progress_bar] 54: @limit_targets = initial_options[:mcollective_limit_targets] 55: @limit_method = Config.instance.rpclimitmethod 56: @limit_seed = initial_options[:limit_seed] || nil 57: @output_format = initial_options[:output_format] || :console 58: @force_direct_request = false 59: @reply_to = initial_options[:reply_to] 60: @discovery_method = initial_options[:discovery_method] || Config.instance.default_discovery_method 61: @discovery_options = initial_options[:discovery_options] || [] 62: @force_display_mode = initial_options[:force_display_mode] || false 63: 64: @batch_size = Integer(initial_options[:batch_size] || 0) 65: @batch_sleep_time = Float(initial_options[:batch_sleep_time] || 1) 66: @batch_mode = @batch_size > 0 67: 68: agent_filter agent 69: 70: @discovery_timeout = @initial_options.fetch(:disctimeout, nil) 71: 72: @collective = @client.collective 73: @ttl = initial_options[:ttl] || Config.instance.ttl 74: 75: # if we can find a DDL for the service override 76: # the timeout of the client so we always magically 77: # wait appropriate amounts of time. 78: # 79: # We add the discovery timeout to the ddl supplied 80: # timeout as the discovery timeout tends to be tuned 81: # for local network conditions and fact source speed 82: # which would other wise not be accounted for and 83: # some results might get missed. 84: # 85: # We do this only if the timeout is the default 5 86: # seconds, so that users cli overrides will still 87: # get applied 88: # 89: # DDLs are required, failure to find a DDL is fatal 90: @ddl = DDL.new(agent) 91: @stats.ddl = @ddl 92: @timeout = @ddl.meta[:timeout] + discovery_timeout if @timeout == 5 93: 94: # allows stderr and stdout to be overridden for testing 95: # but also for web apps that might not want a bunch of stuff 96: # generated to actual file handles 97: if initial_options[:stderr] 98: @stderr = initial_options[:stderr] 99: else 100: @stderr = STDERR 101: @stderr.sync = true 102: end 103: 104: if initial_options[:stdout] 105: @stdout = initial_options[:stdout] 106: else 107: @stdout = STDOUT 108: @stdout.sync = true 109: end 110: end
Sets the agent filter
# File lib/mcollective/rpc/client.rb, line 413 413: def agent_filter(agent) 414: @filter["agent"] << agent 415: @filter["agent"].compact! 416: reset 417: end
# File lib/mcollective/rpc/client.rb, line 692 692: def aggregate_reply(reply, aggregate) 693: return nil unless aggregate 694: 695: aggregate.call_functions(reply) 696: return aggregate 697: rescue Exception => e 698: Log.error("Failed to calculate aggregate summaries for reply from %s, calculating summaries disabled: %s: %s (%s)" % [reply[:senderid], e.backtrace.first, e.to_s, e.class]) 699: return nil 700: end
Sets the batch size, if the size is set to 0 that will disable batch mode
# File lib/mcollective/rpc/client.rb, line 613 613: def batch_size=(limit) 614: raise "Can only set batch size if direct addressing is supported" unless Config.instance.direct_addressing 615: 616: @batch_size = Integer(limit) 617: @batch_mode = @batch_size > 0 618: end
# File lib/mcollective/rpc/client.rb, line 620 620: def batch_sleep_time=(time) 621: raise "Can only set batch sleep time if direct addressing is supported" unless Config.instance.direct_addressing 622: 623: @batch_sleep_time = Float(time) 624: end
Handles traditional calls to the remote agents with full stats blocks, non blocks and everything else supported.
Other methods of calling the nodes can reuse this code by for example specifying custom options and discovery data
# File lib/mcollective/rpc/client.rb, line 820 820: def call_agent(action, args, opts, disc=:auto, &block) 821: # Handle fire and forget requests and make sure 822: # the :process_results value is set appropriately 823: # 824: # specific reply-to requests should be treated like 825: # fire and forget since the client will never get 826: # the responses 827: if args[:process_results] == false || @reply_to 828: return fire_and_forget_request(action, args) 829: else 830: args[:process_results] = true 831: end 832: 833: # Do discovery when no specific discovery array is given 834: # 835: # If an array is given set the force_direct_request hint that 836: # will tell the message object to be a direct request one 837: if disc == :auto 838: discovered = discover 839: else 840: @force_direct_request = true if Config.instance.direct_addressing 841: discovered = disc 842: end 843: 844: req = new_request(action.to_s, args) 845: 846: message = Message.new(req, nil, {:agent => @agent, :type => :request, :collective => @collective, :filter => opts[:filter], :options => opts}) 847: message.discovered_hosts = discovered.clone 848: 849: results = [] 850: respcount = 0 851: 852: if discovered.size > 0 853: message.type = :direct_request if @force_direct_request 854: 855: if @progress && !block_given? 856: twirl = Progress.new 857: @stdout.puts 858: @stdout.print twirl.twirl(respcount, discovered.size) 859: end 860: 861: aggregate = load_aggregate_functions(action, @ddl) 862: 863: @client.req(message) do |resp| 864: respcount += 1 865: 866: if block_given? 867: aggregate = process_results_with_block(action, resp, block, aggregate) 868: else 869: @stdout.print twirl.twirl(respcount, discovered.size) if @progress 870: 871: result, aggregate = process_results_without_block(resp, action, aggregate) 872: 873: results << result 874: end 875: end 876: 877: @stats.aggregate_summary = aggregate.summarize if aggregate 878: @stats.aggregate_failures = aggregate.failed if aggregate 879: @stats.client_stats = @client.stats 880: else 881: @stderr.print("\nNo request sent, we did not discover any nodes.") 882: end 883: 884: @stats.finish_request 885: 886: RPC.stats(@stats) 887: 888: @stdout.print("\n\n") if @progress 889: 890: if block_given? 891: return stats 892: else 893: return [results].flatten 894: end 895: end
Calls an agent in a way very similar to call_agent but it supports batching the queries to the network.
The result sets, stats, block handling etc is all exactly like you would expect from normal call_agent.
This is used by method_missing and works only with direct addressing mode
# File lib/mcollective/rpc/client.rb, line 735 735: def call_agent_batched(action, args, opts, batch_size, sleep_time, &block) 736: raise "Batched requests requires direct addressing" unless Config.instance.direct_addressing 737: raise "Cannot bypass result processing for batched requests" if args[:process_results] == false 738: 739: batch_size = Integer(batch_size) 740: sleep_time = Float(sleep_time) 741: 742: Log.debug("Calling #{agent}##{action} in batches of #{batch_size} with sleep time of #{sleep_time}") 743: 744: @force_direct_request = true 745: 746: discovered = discover 747: results = [] 748: respcount = 0 749: 750: if discovered.size > 0 751: req = new_request(action.to_s, args) 752: 753: aggregate = load_aggregate_functions(action, @ddl) 754: 755: if @progress && !block_given? 756: twirl = Progress.new 757: @stdout.puts 758: @stdout.print twirl.twirl(respcount, discovered.size) 759: end 760: 761: @stats.requestid = nil 762: 763: discovered.in_groups_of(batch_size) do |hosts, last_batch| 764: message = Message.new(req, nil, {:agent => @agent, :type => :direct_request, :collective => @collective, :filter => opts[:filter], :options => opts}) 765: 766: # first time round we let the Message object create a request id 767: # we then re-use it for future requests to keep auditing sane etc 768: @stats.requestid = message.create_reqid unless @stats.requestid 769: message.requestid = @stats.requestid 770: 771: message.discovered_hosts = hosts.clone.compact 772: 773: @client.req(message) do |resp| 774: respcount += 1 775: 776: if block_given? 777: aggregate = process_results_with_block(action, resp, block, aggregate) 778: else 779: @stdout.print twirl.twirl(respcount, discovered.size) if @progress 780: 781: result, aggregate = process_results_without_block(resp, action, aggregate) 782: 783: results << result 784: end 785: end 786: 787: @stats.noresponsefrom.concat @client.stats[:noresponsefrom] 788: @stats.responses += @client.stats[:responses] 789: @stats.blocktime += @client.stats[:blocktime] + sleep_time 790: @stats.totaltime += @client.stats[:totaltime] 791: @stats.discoverytime += @client.stats[:discoverytime] 792: 793: sleep sleep_time unless last_batch 794: end 795: 796: @stats.aggregate_summary = aggregate.summarize if aggregate 797: @stats.aggregate_failures = aggregate.failed if aggregate 798: else 799: @stderr.print("\nNo request sent, we did not discover any nodes.") 800: end 801: 802: @stats.finish_request 803: 804: RPC.stats(@stats) 805: 806: @stdout.print("\n") if @progress 807: 808: if block_given? 809: return stats 810: else 811: return [results].flatten 812: end 813: end
Sets the class filter
# File lib/mcollective/rpc/client.rb, line 389 389: def class_filter(klass) 390: @filter["cf_class"] << klass 391: @filter["cf_class"].compact! 392: reset 393: end
Sets the collective we are communicating with
# File lib/mcollective/rpc/client.rb, line 578 578: def collective=(c) 579: raise "Unknown collective #{c}" unless Config.instance.collectives.include?(c) 580: 581: @collective = c 582: @client.options = options 583: reset 584: end
Set a compound filter
# File lib/mcollective/rpc/client.rb, line 427 427: def compound_filter(filter) 428: @filter["compound"] << Matcher.create_compound_callstack(filter) 429: reset 430: end
Constructs custom requests with custom filters and discovery data the idea is that this would be used in web applications where you might be using a cached copy of data provided by a registration agent to figure out on your own what nodes will be responding and what your filter would be.
This will help you essentially short circuit the traditional cycle of:
mc discover / call / wait for discovered nodes
by doing discovery however you like, contructing a filter and a list of nodes you expect responses from.
Other than that it will work exactly like a normal call, blocks will behave the same way, stats will be handled the same way etcetc
If you just wanted to contact one machine for example with a client that already has other filter options setup you can do:
puppet.custom_request("runonce", {}, ["your.box.com"], {:identity => "your.box.com"})
This will do runonce action on just ‘your.box.com’, no discovery will be done and after receiving just one response it will stop waiting for responses
If direct_addressing is enabled in the config file you can provide an empty hash as a filter, this will force that request to be a directly addressed request which technically does not need filters. If you try to use this mode with direct addressing disabled an exception will be raise
# File lib/mcollective/rpc/client.rb, line 288 288: def custom_request(action, args, expected_agents, filter = {}, &block) 289: validate_request(action, args) 290: 291: if filter == {} && !Config.instance.direct_addressing 292: raise "Attempted to do a filterless custom_request without direct_addressing enabled, preventing unexpected call to all nodes" 293: end 294: 295: @stats.reset 296: 297: custom_filter = Util.empty_filter 298: custom_options = options.clone 299: 300: # merge the supplied filter with the standard empty one 301: # we could just use the merge method but I want to be sure 302: # we dont merge in stuff that isnt actually valid 303: ["identity", "fact", "agent", "cf_class", "compound"].each do |ftype| 304: if filter.include?(ftype) 305: custom_filter[ftype] = [filter[ftype], custom_filter[ftype]].flatten 306: end 307: end 308: 309: # ensure that all filters at least restrict the call to the agent we're a proxy for 310: custom_filter["agent"] << @agent unless custom_filter["agent"].include?(@agent) 311: custom_options[:filter] = custom_filter 312: 313: # Fake out the stats discovery would have put there 314: @stats.discovered_agents([expected_agents].flatten) 315: 316: # Handle fire and forget requests 317: # 318: # If a specific reply-to was set then from the client perspective this should 319: # be a fire and forget request too since no response will ever reach us - it 320: # will go to the reply-to destination 321: if args[:process_results] == false || @reply_to 322: return fire_and_forget_request(action, args, custom_filter) 323: end 324: 325: # Now do a call pretty much exactly like in method_missing except with our own 326: # options and discovery magic 327: if block_given? 328: call_agent(action, args, custom_options, [expected_agents].flatten) do |r| 329: block.call(r) 330: end 331: else 332: call_agent(action, args, custom_options, [expected_agents].flatten) 333: end 334: end
Disconnects cleanly from the middleware
# File lib/mcollective/rpc/client.rb, line 113 113: def disconnect 114: @client.disconnect 115: end
Does discovery based on the filters set, if a discovery was previously done return that else do a new discovery.
Alternatively if identity filters are given and none of them are regular expressions then just use the provided data as discovered data, avoiding discovery
Discovery can be forced if direct_addressing is enabled by passing in an array of nodes with :nodes or JSON data like those produced by mcollective RPC JSON output using :json
Will show a message indicating its doing discovery if running verbose or if the :verbose flag is passed in.
Use reset to force a new discovery
# File lib/mcollective/rpc/client.rb, line 459 459: def discover(flags={}) 460: flags.keys.each do |key| 461: raise "Unknown option #{key} passed to discover" unless [:verbose, :hosts, :nodes, :json].include?(key) 462: end 463: 464: flags.include?(:verbose) ? verbose = flags[:verbose] : verbose = @verbose 465: 466: verbose = false unless @output_format == :console 467: 468: # flags[:nodes] and flags[:hosts] are the same thing, we should never have 469: # allowed :hosts as that was inconsistent with the established terminology 470: flags[:nodes] = flags.delete(:hosts) if flags.include?(:hosts) 471: 472: reset if flags[:nodes] || flags[:json] 473: 474: unless @discovered_agents 475: # if either hosts or JSON is supplied try to figure out discovery data from there 476: # if direct_addressing is not enabled this is a critical error as the user might 477: # not have supplied filters so raise an exception 478: if flags[:nodes] || flags[:json] 479: raise "Can only supply discovery data if direct_addressing is enabled" unless Config.instance.direct_addressing 480: 481: hosts = [] 482: 483: if flags[:nodes] 484: hosts = Helpers.extract_hosts_from_array(flags[:nodes]) 485: elsif flags[:json] 486: hosts = Helpers.extract_hosts_from_json(flags[:json]) 487: end 488: 489: raise "Could not find any hosts in discovery data provided" if hosts.empty? 490: 491: @discovered_agents = hosts 492: @force_direct_request = true 493: 494: # if an identity filter is supplied and it is all strings no regex we can use that 495: # as discovery data, technically the identity filter is then redundant if we are 496: # in direct addressing mode and we could empty it out but this use case should 497: # only really be for a few -I's on the CLI 498: # 499: # For safety we leave the filter in place for now, that way we can support this 500: # enhancement also in broadcast mode. 501: # 502: # This is only needed for the 'mc' discovery method, other methods might change 503: # the concept of identity to mean something else so we should pass the full 504: # identity filter to them 505: elsif options[:filter]["identity"].size > 0 && @discovery_method == "mc" 506: regex_filters = options[:filter]["identity"].select{|i| i.match("^\/")}.size 507: 508: if regex_filters == 0 509: @discovered_agents = options[:filter]["identity"].clone 510: @force_direct_request = true if Config.instance.direct_addressing 511: end 512: end 513: end 514: 515: # All else fails we do it the hard way using a traditional broadcast 516: unless @discovered_agents 517: @stats.time_discovery :start 518: 519: @client.options = options 520: 521: # if compound filters are used the only real option is to use the mc 522: # discovery plugin since its the only capable of using data queries etc 523: # and we do not want to degrade that experience just to allow compounds 524: # on other discovery plugins the UX would be too bad raising complex sets 525: # of errors etc. 526: @client.discoverer.force_discovery_method_by_filter(options[:filter]) 527: 528: if verbose 529: actual_timeout = @client.discoverer.discovery_timeout(discovery_timeout, options[:filter]) 530: 531: if actual_timeout > 0 532: @stderr.print("Discovering hosts using the %s method for %d second(s) .... " % [@client.discoverer.discovery_method, actual_timeout]) 533: else 534: @stderr.print("Discovering hosts using the %s method .... " % [@client.discoverer.discovery_method]) 535: end 536: end 537: 538: # if the requested limit is a pure number and not a percent 539: # and if we're configured to use the first found hosts as the 540: # limit method then pass in the limit thus minimizing the amount 541: # of work we do in the discover phase and speeding it up significantly 542: if @limit_method == :first and @limit_targets.is_a?(Fixnum) 543: @discovered_agents = @client.discover(@filter, discovery_timeout, @limit_targets) 544: else 545: @discovered_agents = @client.discover(@filter, discovery_timeout) 546: end 547: 548: @stderr.puts(@discovered_agents.size) if verbose 549: 550: @force_direct_request = @client.discoverer.force_direct_mode? 551: 552: @stats.time_discovery :end 553: end 554: 555: @stats.discovered_agents(@discovered_agents) 556: RPC.discovered(@discovered_agents) 557: 558: @discovered_agents 559: end
Sets the discovery method. If we change the method there are a number of steps to take:
- set the new method - if discovery options were provided, re-set those to initially provided ones else clear them as they might now apply to a different provider - update the client options so it knows there is a new discovery method in force - reset discovery data forcing a discover on the next request
The remaining item is the discovery timeout, we leave that as is since that is the user supplied timeout either via initial options or via specifically setting it on the client.
# File lib/mcollective/rpc/client.rb, line 369 369: def discovery_method=(method) 370: @discovery_method = method 371: 372: if @initial_options[:discovery_options] 373: @discovery_options = @initial_options[:discovery_options] 374: else 375: @discovery_options.clear 376: end 377: 378: @client.options = options 379: 380: reset 381: end
# File lib/mcollective/rpc/client.rb, line 383 383: def discovery_options=(options) 384: @discovery_options = [options].flatten 385: reset 386: end
# File lib/mcollective/rpc/client.rb, line 336 336: def discovery_timeout 337: return @discovery_timeout if @discovery_timeout 338: return @client.discoverer.ddl.meta[:timeout] 339: end
# File lib/mcollective/rpc/client.rb, line 341 341: def discovery_timeout=(timeout) 342: @discovery_timeout = Float(timeout) 343: 344: # we calculate the overall timeout from the DDL of the agent and 345: # the supplied discovery timeout unless someone specifically 346: # specifies a timeout to the constructor 347: # 348: # But if we also then specifically set a discovery_timeout on the 349: # agent that has to override the supplied timeout so we then 350: # calculate a correct timeout based on DDL timeout and the 351: # supplied discovery timeout 352: @timeout = @ddl.meta[:timeout] + discovery_timeout 353: end
Sets the fact filter
# File lib/mcollective/rpc/client.rb, line 396 396: def fact_filter(fact, value=nil, operator="=") 397: return if fact.nil? 398: return if fact == false 399: 400: if value.nil? 401: parsed = Util.parse_fact_string(fact) 402: @filter["fact"] << parsed unless parsed == false 403: else 404: parsed = Util.parse_fact_string("#{fact}#{operator}#{value}") 405: @filter["fact"] << parsed unless parsed == false 406: end 407: 408: @filter["fact"].compact! 409: reset 410: end
for requests that do not care for results just return the request id and don‘t do any of the response processing.
We send the :process_results flag with to the nodes so they can make decisions based on that.
Should only be called via method_missing
# File lib/mcollective/rpc/client.rb, line 715 715: def fire_and_forget_request(action, args, filter=nil) 716: validate_request(action, args) 717: 718: req = new_request(action.to_s, args) 719: 720: filter = options[:filter] unless filter 721: 722: message = Message.new(req, nil, {:agent => @agent, :type => :request, :collective => @collective, :filter => filter, :options => options}) 723: message.reply_to = @reply_to if @reply_to 724: 725: return @client.sendreq(message, nil) 726: end
Sets the identity filter
# File lib/mcollective/rpc/client.rb, line 420 420: def identity_filter(identity) 421: @filter["identity"] << identity 422: @filter["identity"].compact! 423: reset 424: end
Sets and sanity check the limit_method variable used to determine how to limit targets if limit_targets is set
# File lib/mcollective/rpc/client.rb, line 604 604: def limit_method=(method) 605: method = method.to_sym unless method.is_a?(Symbol) 606: 607: raise "Unknown limit method #{method} must be :random or :first" unless [:random, :first].include?(method) 608: 609: @limit_method = method 610: end
Sets and sanity checks the limit_targets variable used to restrict how many nodes we‘ll target
# File lib/mcollective/rpc/client.rb, line 588 588: def limit_targets=(limit) 589: if limit.is_a?(String) 590: raise "Invalid limit specified: #{limit} valid limits are /^\d+%*$/" unless limit =~ /^\d+%*$/ 591: 592: begin 593: @limit_targets = Integer(limit) 594: rescue 595: @limit_targets = limit 596: end 597: else 598: @limit_targets = Integer(limit) 599: end 600: end
# File lib/mcollective/rpc/client.rb, line 681 681: def load_aggregate_functions(action, ddl) 682: return nil unless ddl 683: return nil unless ddl.action_interface(action).keys.include?(:aggregate) 684: 685: return Aggregate.new(ddl.action_interface(action)) 686: 687: rescue => e 688: Log.error("Failed to load aggregate functions, calculating summaries disabled: %s: %s (%s)" % [e.backtrace.first, e.to_s, e.class]) 689: return nil 690: end
Magic handler to invoke remote methods
Once the stub is created using the constructor or the RPC#rpcclient helper you can call remote actions easily:
ret = rpc.echo(:msg => "hello world")
This will call the ‘echo’ action of the ‘rpctest’ agent and return the result as an array, the array will be a simplified result set from the usual full MCollective::Client#req with additional error codes and error text:
{
:sender => "remote.box.com", :statuscode => 0, :statusmsg => "OK", :data => "hello world"
}
If :statuscode is 0 then everything went find, if it‘s 1 then you supplied the correct arguments etc but the request could not be completed, you‘ll find a human parsable reason in :statusmsg then.
Codes 2 to 5 maps directly to UnknownRPCAction, MissingRPCData, InvalidRPCData and UnknownRPCError see below for a description of those, in each case :statusmsg would be the reason for failure.
To get access to the full result of the MCollective::Client#req calls you can pass in a block:
rpc.echo(:msg => "hello world") do |resp| pp resp end
In this case resp will the result from MCollective::Client#req. Instead of returning simple text and codes as above you‘ll also need to handle the following exceptions:
UnknownRPCAction - There is no matching action on the agent MissingRPCData - You did not supply all the needed parameters for the action InvalidRPCData - The data you did supply did not pass validation UnknownRPCError - Some other error prevented the agent from running
During calls a progress indicator will be shown of how many results we‘ve received against how many nodes were discovered, you can disable this by setting progress to false:
rpc.progress = false
This supports a 2nd mode where it will send the SimpleRPC request and never handle the responses. It‘s a bit like UDP, it sends the request with the filter attached and you only get back the requestid, you have no indication about results.
You can invoke this using:
puts rpc.echo(:process_results => false)
This will output just the request id.
Batched processing is supported:
printrpc rpc.ping(:batch_size => 5)
This will do everything exactly as normal but communicate to only 5 agents at a time
# File lib/mcollective/rpc/client.rb, line 223 223: def method_missing(method_name, *args, &block) 224: # set args to an empty hash if nothings given 225: args = args[0] 226: args = {} if args.nil? 227: 228: action = method_name.to_s 229: 230: @stats.reset 231: 232: validate_request(action, args) 233: 234: # if a global batch size is set just use that else set it 235: # in the case that it was passed as an argument 236: batch_mode = args.include?(:batch_size) || @batch_mode 237: batch_size = args.delete(:batch_size) || @batch_size 238: batch_sleep_time = args.delete(:batch_sleep_time) || @batch_sleep_time 239: 240: # if we were given a batch_size argument thats 0 and batch_mode was 241: # determined to be on via global options etc this will allow a batch_size 242: # of 0 to disable or batch_mode for this call only 243: batch_mode = (batch_mode && Integer(batch_size) > 0) 244: 245: # Handle single target requests by doing discovery and picking 246: # a random node. Then do a custom request specifying a filter 247: # that will only match the one node. 248: if @limit_targets 249: target_nodes = pick_nodes_from_discovered(@limit_targets) 250: Log.debug("Picked #{target_nodes.join(',')} as limited target(s)") 251: 252: custom_request(action, args, target_nodes, {"identity" => /^(#{target_nodes.join('|')})$/}, &block) 253: elsif batch_mode 254: call_agent_batched(action, args, options, batch_size, batch_sleep_time, &block) 255: else 256: call_agent(action, args, options, :auto, &block) 257: end 258: end
Creates a suitable request hash for the SimpleRPC agent.
You‘d use this if you ever wanted to take care of sending requests on your own - perhaps via Client#sendreq if you didn‘t care for responses.
In that case you can just do:
msg = your_rpc.new_request("some_action", :foo => :bar) filter = your_rpc.filter your_rpc.client.sendreq(msg, msg[:agent], filter)
This will send a SimpleRPC request to the action some_action with arguments :foo = :bar, it will return immediately and you will have no indication at all if the request was receieved or not
Clearly the use of this technique should be limited and done only if your code requires such a thing
# File lib/mcollective/rpc/client.rb, line 141 141: def new_request(action, data) 142: callerid = PluginManager["security_plugin"].callerid 143: 144: raise 'callerid received from security plugin is not valid' unless PluginManager["security_plugin"].valid_callerid?(callerid) 145: 146: {:agent => @agent, 147: :action => action, 148: :caller => callerid, 149: :data => data} 150: end
Provides a normal options hash like you would get from Optionparser
# File lib/mcollective/rpc/client.rb, line 563 563: def options 564: {:disctimeout => discovery_timeout, 565: :timeout => @timeout, 566: :verbose => @verbose, 567: :filter => @filter, 568: :collective => @collective, 569: :output_format => @output_format, 570: :ttl => @ttl, 571: :discovery_method => @discovery_method, 572: :discovery_options => @discovery_options, 573: :force_display_mode => @force_display_mode, 574: :config => @config} 575: end
Pick a number of nodes from the discovered nodes
The count should be a string that can be either just a number or a percentage like 10%
It will select nodes from the discovered list based on the rpclimitmethod configuration option which can be either :first or anything else
- :first would be a simple way to do a distance based selection - anything else will just pick one at random - if random chosen, and batch-seed set, then set srand for the generator, and reset afterwards
# File lib/mcollective/rpc/client.rb, line 640 640: def pick_nodes_from_discovered(count) 641: if count =~ /%$/ 642: pct = Integer((discover.size * (count.to_f / 100))) 643: pct == 0 ? count = 1 : count = pct 644: else 645: count = Integer(count) 646: end 647: 648: return discover if discover.size <= count 649: 650: result = [] 651: 652: if @limit_method == :first 653: return discover[0, count] 654: else 655: # we delete from the discovered list because we want 656: # to be sure there is no chance that the same node will 657: # be randomly picked twice. So we have to clone the 658: # discovered list else this method will only ever work 659: # once per discovery cycle and not actually return the 660: # right nodes. 661: haystack = discover.clone 662: 663: if @limit_seed 664: haystack.sort! 665: srand(@limit_seed) 666: end 667: 668: count.times do 669: rnd = rand(haystack.size) 670: result << haystack.delete_at(rnd) 671: end 672: 673: # Reset random number generator to fresh seed 674: # As our seed from options is most likely short 675: srand if @limit_seed 676: end 677: 678: [result].flatten 679: end
process client requests by calling a block on each result in this mode we do not do anything fancy with the result objects and we raise exceptions if there are problems with the data
# File lib/mcollective/rpc/client.rb, line 920 920: def process_results_with_block(action, resp, block, aggregate) 921: @stats.node_responded(resp[:senderid]) 922: 923: result = rpc_result_from_reply(@agent, action, resp) 924: aggregate = aggregate_reply(result, aggregate) if aggregate 925: 926: if resp[:body][:statuscode] == 0 || resp[:body][:statuscode] == 1 927: @stats.ok if resp[:body][:statuscode] == 0 928: @stats.fail if resp[:body][:statuscode] == 1 929: @stats.time_block_execution :start 930: 931: case block.arity 932: when 1 933: block.call(resp) 934: when 2 935: block.call(resp, result) 936: end 937: 938: @stats.time_block_execution :end 939: else 940: @stats.fail 941: 942: case resp[:body][:statuscode] 943: when 2 944: raise UnknownRPCAction, resp[:body][:statusmsg] 945: when 3 946: raise MissingRPCData, resp[:body][:statusmsg] 947: when 4 948: raise InvalidRPCData, resp[:body][:statusmsg] 949: when 5 950: raise UnknownRPCError, resp[:body][:statusmsg] 951: end 952: end 953: 954: return aggregate 955: end
Handles result sets that has no block associated, sets fails and ok in the stats object and return a hash of the response to send to the caller
# File lib/mcollective/rpc/client.rb, line 900 900: def process_results_without_block(resp, action, aggregate) 901: @stats.node_responded(resp[:senderid]) 902: 903: result = rpc_result_from_reply(@agent, action, resp) 904: aggregate = aggregate_reply(result, aggregate) if aggregate 905: 906: if resp[:body][:statuscode] == 0 || resp[:body][:statuscode] == 1 907: @stats.ok if resp[:body][:statuscode] == 0 908: @stats.fail if resp[:body][:statuscode] == 1 909: else 910: @stats.fail 911: end 912: 913: [result, aggregate] 914: end
Resets various internal parts of the class, most importantly it clears out the cached discovery
# File lib/mcollective/rpc/client.rb, line 434 434: def reset 435: @discovered_agents = nil 436: end
Reet the filter to an empty one
# File lib/mcollective/rpc/client.rb, line 439 439: def reset_filter 440: @filter = Util.empty_filter 441: agent_filter @agent 442: end
# File lib/mcollective/rpc/client.rb, line 702 702: def rpc_result_from_reply(agent, action, reply) 703: Result.new(agent, action, {:sender => reply[:senderid], :statuscode => reply[:body][:statuscode], 704: :statusmsg => reply[:body][:statusmsg], :data => reply[:body][:data]}) 705: end
For the provided arguments and action the input arguments get modified by supplying any defaults provided in the DDL for arguments that were not supplied in the request
We then pass the modified arguments to the DDL for validation
# File lib/mcollective/rpc/client.rb, line 157 157: def validate_request(action, args) 158: raise "No DDL found for agent %s cannot validate inputs" % @agent unless @ddl 159: 160: @ddl.set_default_input_arguments(action, args) 161: @ddl.validate_rpc_request(action, args) 162: end