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 401 401: def agent_filter(agent) 402: @filter["agent"] << agent 403: @filter["agent"].compact! 404: reset 405: end
# File lib/mcollective/rpc/client.rb, line 680 680: def aggregate_reply(reply, aggregate) 681: return nil unless aggregate 682: 683: aggregate.call_functions(reply) 684: return aggregate 685: rescue Exception => e 686: 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]) 687: return nil 688: end
Sets the batch size, if the size is set to 0 that will disable batch mode
# File lib/mcollective/rpc/client.rb, line 601 601: def batch_size=(limit) 602: raise "Can only set batch size if direct addressing is supported" unless Config.instance.direct_addressing 603: 604: @batch_size = Integer(limit) 605: @batch_mode = @batch_size > 0 606: end
# File lib/mcollective/rpc/client.rb, line 608 608: def batch_sleep_time=(time) 609: raise "Can only set batch sleep time if direct addressing is supported" unless Config.instance.direct_addressing 610: 611: @batch_sleep_time = Float(time) 612: 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 808 808: def call_agent(action, args, opts, disc=:auto, &block) 809: # Handle fire and forget requests and make sure 810: # the :process_results value is set appropriately 811: # 812: # specific reply-to requests should be treated like 813: # fire and forget since the client will never get 814: # the responses 815: if args[:process_results] == false || @reply_to 816: return fire_and_forget_request(action, args) 817: else 818: args[:process_results] = true 819: end 820: 821: # Do discovery when no specific discovery array is given 822: # 823: # If an array is given set the force_direct_request hint that 824: # will tell the message object to be a direct request one 825: if disc == :auto 826: discovered = discover 827: else 828: @force_direct_request = true if Config.instance.direct_addressing 829: discovered = disc 830: end 831: 832: req = new_request(action.to_s, args) 833: 834: message = Message.new(req, nil, {:agent => @agent, :type => :request, :collective => @collective, :filter => opts[:filter], :options => opts}) 835: message.discovered_hosts = discovered.clone 836: 837: results = [] 838: respcount = 0 839: 840: if discovered.size > 0 841: message.type = :direct_request if @force_direct_request 842: 843: if @progress && !block_given? 844: twirl = Progress.new 845: @stdout.puts 846: @stdout.print twirl.twirl(respcount, discovered.size) 847: end 848: 849: aggregate = load_aggregate_functions(action, @ddl) 850: 851: @client.req(message) do |resp| 852: respcount += 1 853: 854: if block_given? 855: aggregate = process_results_with_block(action, resp, block, aggregate) 856: else 857: @stdout.print twirl.twirl(respcount, discovered.size) if @progress 858: 859: result, aggregate = process_results_without_block(resp, action, aggregate) 860: 861: results << result 862: end 863: end 864: 865: @stats.aggregate_summary = aggregate.summarize if aggregate 866: @stats.aggregate_failures = aggregate.failed if aggregate 867: @stats.client_stats = @client.stats 868: else 869: @stderr.print("\nNo request sent, we did not discover any nodes.") 870: end 871: 872: @stats.finish_request 873: 874: RPC.stats(@stats) 875: 876: @stdout.print("\n\n") if @progress 877: 878: if block_given? 879: return stats 880: else 881: return [results].flatten 882: end 883: 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 723 723: def call_agent_batched(action, args, opts, batch_size, sleep_time, &block) 724: raise "Batched requests requires direct addressing" unless Config.instance.direct_addressing 725: raise "Cannot bypass result processing for batched requests" if args[:process_results] == false 726: 727: batch_size = Integer(batch_size) 728: sleep_time = Float(sleep_time) 729: 730: Log.debug("Calling #{agent}##{action} in batches of #{batch_size} with sleep time of #{sleep_time}") 731: 732: @force_direct_request = true 733: 734: discovered = discover 735: results = [] 736: respcount = 0 737: 738: if discovered.size > 0 739: req = new_request(action.to_s, args) 740: 741: aggregate = load_aggregate_functions(action, @ddl) 742: 743: if @progress && !block_given? 744: twirl = Progress.new 745: @stdout.puts 746: @stdout.print twirl.twirl(respcount, discovered.size) 747: end 748: 749: @stats.requestid = nil 750: 751: discovered.in_groups_of(batch_size) do |hosts, last_batch| 752: message = Message.new(req, nil, {:agent => @agent, :type => :direct_request, :collective => @collective, :filter => opts[:filter], :options => opts}) 753: 754: # first time round we let the Message object create a request id 755: # we then re-use it for future requests to keep auditing sane etc 756: @stats.requestid = message.create_reqid unless @stats.requestid 757: message.requestid = @stats.requestid 758: 759: message.discovered_hosts = hosts.clone.compact 760: 761: @client.req(message) do |resp| 762: respcount += 1 763: 764: if block_given? 765: aggregate = process_results_with_block(action, resp, block, aggregate) 766: else 767: @stdout.print twirl.twirl(respcount, discovered.size) if @progress 768: 769: result, aggregate = process_results_without_block(resp, action, aggregate) 770: 771: results << result 772: end 773: end 774: 775: @stats.noresponsefrom.concat @client.stats[:noresponsefrom] 776: @stats.responses += @client.stats[:responses] 777: @stats.blocktime += @client.stats[:blocktime] + sleep_time 778: @stats.totaltime += @client.stats[:totaltime] 779: @stats.discoverytime += @client.stats[:discoverytime] 780: 781: sleep sleep_time unless last_batch 782: end 783: 784: @stats.aggregate_summary = aggregate.summarize if aggregate 785: @stats.aggregate_failures = aggregate.failed if aggregate 786: else 787: @stderr.print("\nNo request sent, we did not discover any nodes.") 788: end 789: 790: @stats.finish_request 791: 792: RPC.stats(@stats) 793: 794: @stdout.print("\n") if @progress 795: 796: if block_given? 797: return stats 798: else 799: return [results].flatten 800: end 801: end
Sets the class filter
# File lib/mcollective/rpc/client.rb, line 377 377: def class_filter(klass) 378: @filter["cf_class"] << klass 379: @filter["cf_class"].compact! 380: reset 381: end
Sets the collective we are communicating with
# File lib/mcollective/rpc/client.rb, line 566 566: def collective=(c) 567: raise "Unknown collective #{c}" unless Config.instance.collectives.include?(c) 568: 569: @collective = c 570: @client.options = options 571: reset 572: end
Set a compound filter
# File lib/mcollective/rpc/client.rb, line 415 415: def compound_filter(filter) 416: @filter["compound"] << Matcher.create_compound_callstack(filter) 417: reset 418: 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 276 276: def custom_request(action, args, expected_agents, filter = {}, &block) 277: @ddl.validate_rpc_request(action, args) if @ddl 278: 279: if filter == {} && !Config.instance.direct_addressing 280: raise "Attempted to do a filterless custom_request without direct_addressing enabled, preventing unexpected call to all nodes" 281: end 282: 283: @stats.reset 284: 285: custom_filter = Util.empty_filter 286: custom_options = options.clone 287: 288: # merge the supplied filter with the standard empty one 289: # we could just use the merge method but I want to be sure 290: # we dont merge in stuff that isnt actually valid 291: ["identity", "fact", "agent", "cf_class", "compound"].each do |ftype| 292: if filter.include?(ftype) 293: custom_filter[ftype] = [filter[ftype], custom_filter[ftype]].flatten 294: end 295: end 296: 297: # ensure that all filters at least restrict the call to the agent we're a proxy for 298: custom_filter["agent"] << @agent unless custom_filter["agent"].include?(@agent) 299: custom_options[:filter] = custom_filter 300: 301: # Fake out the stats discovery would have put there 302: @stats.discovered_agents([expected_agents].flatten) 303: 304: # Handle fire and forget requests 305: # 306: # If a specific reply-to was set then from the client perspective this should 307: # be a fire and forget request too since no response will ever reach us - it 308: # will go to the reply-to destination 309: if args[:process_results] == false || @reply_to 310: return fire_and_forget_request(action, args, custom_filter) 311: end 312: 313: # Now do a call pretty much exactly like in method_missing except with our own 314: # options and discovery magic 315: if block_given? 316: call_agent(action, args, custom_options, [expected_agents].flatten) do |r| 317: block.call(r) 318: end 319: else 320: call_agent(action, args, custom_options, [expected_agents].flatten) 321: end 322: 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 447 447: def discover(flags={}) 448: flags.keys.each do |key| 449: raise "Unknown option #{key} passed to discover" unless [:verbose, :hosts, :nodes, :json].include?(key) 450: end 451: 452: flags.include?(:verbose) ? verbose = flags[:verbose] : verbose = @verbose 453: 454: verbose = false unless @output_format == :console 455: 456: # flags[:nodes] and flags[:hosts] are the same thing, we should never have 457: # allowed :hosts as that was inconsistent with the established terminology 458: flags[:nodes] = flags.delete(:hosts) if flags.include?(:hosts) 459: 460: reset if flags[:nodes] || flags[:json] 461: 462: unless @discovered_agents 463: # if either hosts or JSON is supplied try to figure out discovery data from there 464: # if direct_addressing is not enabled this is a critical error as the user might 465: # not have supplied filters so raise an exception 466: if flags[:nodes] || flags[:json] 467: raise "Can only supply discovery data if direct_addressing is enabled" unless Config.instance.direct_addressing 468: 469: hosts = [] 470: 471: if flags[:nodes] 472: hosts = Helpers.extract_hosts_from_array(flags[:nodes]) 473: elsif flags[:json] 474: hosts = Helpers.extract_hosts_from_json(flags[:json]) 475: end 476: 477: raise "Could not find any hosts in discovery data provided" if hosts.empty? 478: 479: @discovered_agents = hosts 480: @force_direct_request = true 481: 482: # if an identity filter is supplied and it is all strings no regex we can use that 483: # as discovery data, technically the identity filter is then redundant if we are 484: # in direct addressing mode and we could empty it out but this use case should 485: # only really be for a few -I's on the CLI 486: # 487: # For safety we leave the filter in place for now, that way we can support this 488: # enhancement also in broadcast mode. 489: # 490: # This is only needed for the 'mc' discovery method, other methods might change 491: # the concept of identity to mean something else so we should pass the full 492: # identity filter to them 493: elsif options[:filter]["identity"].size > 0 && @discovery_method == "mc" 494: regex_filters = options[:filter]["identity"].select{|i| i.match("^\/")}.size 495: 496: if regex_filters == 0 497: @discovered_agents = options[:filter]["identity"].clone 498: @force_direct_request = true if Config.instance.direct_addressing 499: end 500: end 501: end 502: 503: # All else fails we do it the hard way using a traditional broadcast 504: unless @discovered_agents 505: @stats.time_discovery :start 506: 507: @client.options = options 508: 509: # if compound filters are used the only real option is to use the mc 510: # discovery plugin since its the only capable of using data queries etc 511: # and we do not want to degrade that experience just to allow compounds 512: # on other discovery plugins the UX would be too bad raising complex sets 513: # of errors etc. 514: @client.discoverer.force_discovery_method_by_filter(options[:filter]) 515: 516: if verbose 517: actual_timeout = @client.discoverer.discovery_timeout(discovery_timeout, options[:filter]) 518: 519: if actual_timeout > 0 520: @stderr.print("Discovering hosts using the %s method for %d second(s) .... " % [@client.discoverer.discovery_method, actual_timeout]) 521: else 522: @stderr.print("Discovering hosts using the %s method .... " % [@client.discoverer.discovery_method]) 523: end 524: end 525: 526: # if the requested limit is a pure number and not a percent 527: # and if we're configured to use the first found hosts as the 528: # limit method then pass in the limit thus minimizing the amount 529: # of work we do in the discover phase and speeding it up significantly 530: if @limit_method == :first and @limit_targets.is_a?(Fixnum) 531: @discovered_agents = @client.discover(@filter, discovery_timeout, @limit_targets) 532: else 533: @discovered_agents = @client.discover(@filter, discovery_timeout) 534: end 535: 536: @stderr.puts(@discovered_agents.size) if verbose 537: 538: @force_direct_request = @client.discoverer.force_direct_mode? 539: 540: @stats.time_discovery :end 541: end 542: 543: @stats.discovered_agents(@discovered_agents) 544: RPC.discovered(@discovered_agents) 545: 546: @discovered_agents 547: 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 357 357: def discovery_method=(method) 358: @discovery_method = method 359: 360: if @initial_options[:discovery_options] 361: @discovery_options = @initial_options[:discovery_options] 362: else 363: @discovery_options.clear 364: end 365: 366: @client.options = options 367: 368: reset 369: end
# File lib/mcollective/rpc/client.rb, line 371 371: def discovery_options=(options) 372: @discovery_options = [options].flatten 373: reset 374: end
# File lib/mcollective/rpc/client.rb, line 324 324: def discovery_timeout 325: return @discovery_timeout if @discovery_timeout 326: return @client.discoverer.ddl.meta[:timeout] 327: end
# File lib/mcollective/rpc/client.rb, line 329 329: def discovery_timeout=(timeout) 330: @discovery_timeout = Float(timeout) 331: 332: # we calculate the overall timeout from the DDL of the agent and 333: # the supplied discovery timeout unless someone specifically 334: # specifies a timeout to the constructor 335: # 336: # But if we also then specifically set a discovery_timeout on the 337: # agent that has to override the supplied timeout so we then 338: # calculate a correct timeout based on DDL timeout and the 339: # supplied discovery timeout 340: @timeout = @ddl.meta[:timeout] + discovery_timeout 341: end
Sets the fact filter
# File lib/mcollective/rpc/client.rb, line 384 384: def fact_filter(fact, value=nil, operator="=") 385: return if fact.nil? 386: return if fact == false 387: 388: if value.nil? 389: parsed = Util.parse_fact_string(fact) 390: @filter["fact"] << parsed unless parsed == false 391: else 392: parsed = Util.parse_fact_string("#{fact}#{operator}#{value}") 393: @filter["fact"] << parsed unless parsed == false 394: end 395: 396: @filter["fact"].compact! 397: reset 398: 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 703 703: def fire_and_forget_request(action, args, filter=nil) 704: @ddl.validate_rpc_request(action, args) if @ddl 705: 706: req = new_request(action.to_s, args) 707: 708: filter = options[:filter] unless filter 709: 710: message = Message.new(req, nil, {:agent => @agent, :type => :request, :collective => @collective, :filter => filter, :options => options}) 711: message.reply_to = @reply_to if @reply_to 712: 713: return @client.sendreq(message, nil) 714: end
Sets the identity filter
# File lib/mcollective/rpc/client.rb, line 408 408: def identity_filter(identity) 409: @filter["identity"] << identity 410: @filter["identity"].compact! 411: reset 412: 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 592 592: def limit_method=(method) 593: method = method.to_sym unless method.is_a?(Symbol) 594: 595: raise "Unknown limit method #{method} must be :random or :first" unless [:random, :first].include?(method) 596: 597: @limit_method = method 598: 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 576 576: def limit_targets=(limit) 577: if limit.is_a?(String) 578: raise "Invalid limit specified: #{limit} valid limits are /^\d+%*$/" unless limit =~ /^\d+%*$/ 579: 580: begin 581: @limit_targets = Integer(limit) 582: rescue 583: @limit_targets = limit 584: end 585: else 586: @limit_targets = Integer(limit) 587: end 588: end
# File lib/mcollective/rpc/client.rb, line 669 669: def load_aggregate_functions(action, ddl) 670: return nil unless ddl 671: return nil unless ddl.action_interface(action).keys.include?(:aggregate) 672: 673: return Aggregate.new(ddl.action_interface(action)) 674: 675: rescue => e 676: Log.error("Failed to load aggregate functions, calculating summaries disabled: %s: %s (%s)" % [e.backtrace.first, e.to_s, e.class]) 677: return nil 678: 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 211 211: def method_missing(method_name, *args, &block) 212: # set args to an empty hash if nothings given 213: args = args[0] 214: args = {} if args.nil? 215: 216: action = method_name.to_s 217: 218: @stats.reset 219: 220: @ddl.validate_rpc_request(action, args) if @ddl 221: 222: # if a global batch size is set just use that else set it 223: # in the case that it was passed as an argument 224: batch_mode = args.include?(:batch_size) || @batch_mode 225: batch_size = args.delete(:batch_size) || @batch_size 226: batch_sleep_time = args.delete(:batch_sleep_time) || @batch_sleep_time 227: 228: # if we were given a batch_size argument thats 0 and batch_mode was 229: # determined to be on via global options etc this will allow a batch_size 230: # of 0 to disable or batch_mode for this call only 231: batch_mode = (batch_mode && Integer(batch_size) > 0) 232: 233: # Handle single target requests by doing discovery and picking 234: # a random node. Then do a custom request specifying a filter 235: # that will only match the one node. 236: if @limit_targets 237: target_nodes = pick_nodes_from_discovered(@limit_targets) 238: Log.debug("Picked #{target_nodes.join(',')} as limited target(s)") 239: 240: custom_request(action, args, target_nodes, {"identity" => /^(#{target_nodes.join('|')})$/}, &block) 241: elsif batch_mode 242: call_agent_batched(action, args, options, batch_size, batch_sleep_time, &block) 243: else 244: call_agent(action, args, options, :auto, &block) 245: end 246: 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 551 551: def options 552: {:disctimeout => discovery_timeout, 553: :timeout => @timeout, 554: :verbose => @verbose, 555: :filter => @filter, 556: :collective => @collective, 557: :output_format => @output_format, 558: :ttl => @ttl, 559: :discovery_method => @discovery_method, 560: :discovery_options => @discovery_options, 561: :force_display_mode => @force_display_mode, 562: :config => @config} 563: 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 628 628: def pick_nodes_from_discovered(count) 629: if count =~ /%$/ 630: pct = Integer((discover.size * (count.to_f / 100))) 631: pct == 0 ? count = 1 : count = pct 632: else 633: count = Integer(count) 634: end 635: 636: return discover if discover.size <= count 637: 638: result = [] 639: 640: if @limit_method == :first 641: return discover[0, count] 642: else 643: # we delete from the discovered list because we want 644: # to be sure there is no chance that the same node will 645: # be randomly picked twice. So we have to clone the 646: # discovered list else this method will only ever work 647: # once per discovery cycle and not actually return the 648: # right nodes. 649: haystack = discover.clone 650: 651: if @limit_seed 652: haystack.sort! 653: srand(@limit_seed) 654: end 655: 656: count.times do 657: rnd = rand(haystack.size) 658: result << haystack.delete_at(rnd) 659: end 660: 661: # Reset random number generator to fresh seed 662: # As our seed from options is most likely short 663: srand if @limit_seed 664: end 665: 666: [result].flatten 667: 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 908 908: def process_results_with_block(action, resp, block, aggregate) 909: @stats.node_responded(resp[:senderid]) 910: 911: result = rpc_result_from_reply(@agent, action, resp) 912: aggregate = aggregate_reply(result, aggregate) if aggregate 913: 914: if resp[:body][:statuscode] == 0 || resp[:body][:statuscode] == 1 915: @stats.ok if resp[:body][:statuscode] == 0 916: @stats.fail if resp[:body][:statuscode] == 1 917: @stats.time_block_execution :start 918: 919: case block.arity 920: when 1 921: block.call(resp) 922: when 2 923: block.call(resp, result) 924: end 925: 926: @stats.time_block_execution :end 927: else 928: @stats.fail 929: 930: case resp[:body][:statuscode] 931: when 2 932: raise UnknownRPCAction, resp[:body][:statusmsg] 933: when 3 934: raise MissingRPCData, resp[:body][:statusmsg] 935: when 4 936: raise InvalidRPCData, resp[:body][:statusmsg] 937: when 5 938: raise UnknownRPCError, resp[:body][:statusmsg] 939: end 940: end 941: 942: return aggregate 943: 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 888 888: def process_results_without_block(resp, action, aggregate) 889: @stats.node_responded(resp[:senderid]) 890: 891: result = rpc_result_from_reply(@agent, action, resp) 892: aggregate = aggregate_reply(result, aggregate) if aggregate 893: 894: if resp[:body][:statuscode] == 0 || resp[:body][:statuscode] == 1 895: @stats.ok if resp[:body][:statuscode] == 0 896: @stats.fail if resp[:body][:statuscode] == 1 897: else 898: @stats.fail 899: end 900: 901: [result, aggregate] 902: end
Resets various internal parts of the class, most importantly it clears out the cached discovery
# File lib/mcollective/rpc/client.rb, line 422 422: def reset 423: @discovered_agents = nil 424: end
Reet the filter to an empty one
# File lib/mcollective/rpc/client.rb, line 427 427: def reset_filter 428: @filter = Util.empty_filter 429: agent_filter @agent 430: end