Class: MCollective::Client

Inherits:
Object
  • Object
show all
Defined in:
lib/mcollective/client.rb

Overview

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(configfile) ⇒ Client

Returns a new instance of Client.



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# File 'lib/mcollective/client.rb', line 6

def initialize(configfile)
  @config = Config.instance
  @config.loadconfig(configfile) unless @config.configured

  @connection = PluginManager["connector_plugin"]
  @security = PluginManager["security_plugin"]

  @security.initiated_by = :client
  @options = nil
  @subscriptions = {}

  @discoverer = Discovery.new(self)
  @connection.connect
end

Instance Attribute Details

#discoverer ⇒ Object

Returns the value of attribute discoverer.



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# File 'lib/mcollective/client.rb', line 4

def discoverer
  @discoverer
end

#options ⇒ Object

Returns the value of attribute options.



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# File 'lib/mcollective/client.rb', line 4

def options
  @options
end

#stats ⇒ Object

Returns the value of attribute stats.



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# File 'lib/mcollective/client.rb', line 4

def stats
  @stats
end

Instance Method Details

#collective ⇒ Object

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



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# File 'lib/mcollective/client.rb', line 23

def collective
  if @options[:collective].nil?
    @config.main_collective
  else
    @options[:collective]
  end
end

#disconnect ⇒ Object

Disconnects cleanly from the middleware



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# File 'lib/mcollective/client.rb', line 32

def disconnect
  Log.debug("Disconnecting from the middleware")
  @connection.disconnect
end

#discover(filter, timeout, limit = 0) ⇒ Object

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



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# File 'lib/mcollective/client.rb', line 115

def discover(filter, timeout, limit=0)
  discovered = @discoverer.discover(filter, timeout, limit)
end

#discovered_req(body, agent, options = false) ⇒ Object 



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# File 'lib/mcollective/client.rb', line 177

def discovered_req(body, agent, options=false)
  raise "Client#discovered_req has been removed, please port your agent and client to the SimpleRPC framework"
end

#display_stats(stats, options = false, caption = "stomp call summary") ⇒ Object

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



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# File 'lib/mcollective/client.rb', line 182

def display_stats(stats, options=false, caption="stomp call summary")
  options = @options unless options

  if options[:verbose]
    puts("\n---- #{caption} ----")

    if stats[:discovered]
      puts("           Nodes: #{stats[:discovered]} / #{stats[:responses]}")
    else
      puts("           Nodes: #{stats[:responses]}")
    end

    printf("      Start Time: %s\n", Time.at(stats[:starttime]))
    printf("  Discovery Time: %.2fms\n", stats[:discoverytime] * 1000)
    printf("      Agent Time: %.2fms\n", stats[:blocktime] * 1000)
    printf("      Total Time: %.2fms\n", stats[:totaltime] * 1000)

  else
    if stats[:discovered]
      printf("\nFinished processing %d / %d hosts in %.2f ms\n\n", stats[:responses], stats[:discovered], stats[:blocktime] * 1000)
    else
      printf("\nFinished processing %d hosts in %.2f ms\n\n", stats[:responses], stats[:blocktime] * 1000)
    end
  end

  if stats[:noresponsefrom].size > 0
    puts("\nNo response from:\n")

    stats[:noresponsefrom].each do |c|
      puts if c % 4 == 1
      printf("%30s", c)
    end

    puts
  end
end

#receive(requestid = nil) ⇒ Object

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.



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# File 'lib/mcollective/client.rb', line 85

def receive(requestid = nil)
  reply = nil

  begin
    reply = @connection.receive
    reply.type = :reply
    reply.expected_msgid = requestid

    reply.decode!

    reply.payload[:senderid] = Digest::MD5.hexdigest(reply.payload[:senderid]) if ENV.include?("MCOLLECTIVE_ANON")

    raise(MsgDoesNotMatchRequestID, "Message reqid #{requestid} does not match our reqid #{reply.requestid}") unless reply.requestid == requestid
  rescue SecurityValidationFailed => e
    Log.warn("Ignoring a message that did not pass security validations")
    retry
  rescue MsgDoesNotMatchRequestID => e
    Log.debug("Ignoring a message for some other client")
    retry
  end

  reply
end

#req(body, agent = nil, options = false, waitfor = 0) ⇒ Object

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



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# File 'lib/mcollective/client.rb', line 127

def req(body, agent=nil, options=false, waitfor=0)
  if body.is_a?(Message)
    agent = body.agent
    waitfor = body.discovered_hosts.size || 0
    @options = body.options
  end

  @options = options if options

  stat = {:starttime => Time.now.to_f, :discoverytime => 0, :blocktime => 0, :totaltime => 0}

  timeout = @discoverer.discovery_timeout(@options[:timeout], @options[:filter])

  STDOUT.sync = true

  hosts_responded = 0
  reqid = nil

  begin
    Log.debug("Publishing request to agent %s with timeout %d" % [agent, timeout])

    Timeout.timeout(timeout) do
      reqid = sendreq(body, agent, @options[:filter])

      loop do
        resp = receive(reqid)

        hosts_responded += 1

        yield(resp.payload)

        break if (waitfor != 0 && hosts_responded >= waitfor)
      end
    end
  rescue Interrupt => e
  rescue Timeout::Error => e
  ensure
    unsubscribe(agent, :reply)
  end

  stat[:totaltime] = Time.now.to_f - stat[:starttime]
  stat[:blocktime] = stat[:totaltime] - stat[:discoverytime]
  stat[:responses] = hosts_responded
  stat[:noresponsefrom] = []
  stat[:requestid] = reqid

  @stats = stat
  return stat
end

#sendreq(msg, agent, filter = {}) ⇒ Object

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



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# File 'lib/mcollective/client.rb', line 39

def sendreq(msg, agent, filter = {})
  if msg.is_a?(Message)
    request = msg
    agent = request.agent
  else
    ttl = @options[:ttl] || @config.ttl
    request = Message.new(msg, nil, {:agent => agent, :type => :request, :collective => collective, :filter => filter, :ttl => ttl})
    request.reply_to = @options[:reply_to] if @options[:reply_to]
  end

  request.encode!

  Log.debug("Sending request #{request.requestid} to the #{request.agent} agent with ttl #{request.ttl} in collective #{request.collective}")

  subscribe(agent, :reply) unless request.reply_to

  request.publish

  request.requestid
end

#subscribe(agent, type) ⇒ Object 



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# File 'lib/mcollective/client.rb', line 60

def subscribe(agent, type)
  unless @subscriptions.include?(agent)
    subscription = Util.make_subscriptions(agent, type, collective)
    Log.debug("Subscribing to #{type} target for agent #{agent}")

    Util.subscribe(subscription)
    @subscriptions[agent] = 1
  end
end

#unsubscribe(agent, type) ⇒ Object 



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# File 'lib/mcollective/client.rb', line 70

def unsubscribe(agent, type)
  if @subscriptions.include?(agent)
    subscription = Util.make_subscriptions(agent, type, collective)
    Log.debug("Unsubscribing #{type} target for #{agent}")

    Util.unsubscribe(subscription)
    @subscriptions.delete(agent)
  end
end