Class: Sfp::BSig

Inherits:
Object
  • Object
show all
Includes:
Helper::Net
Defined in:
lib/sfpagent/bsig.rb

Constant Summary collapse

SleepTime = 
5
MaxTries = 
5
SatisfierPath = 
'/bsig/satisfier'
Home = 
((Process.euid == 0 and File.directory?('/var')) ? '/var/sfpagent' : File.expand_path(Dir.home + '/.sfpagent'))
SatisfierLockFile = 
"#{Home}/bsig.satisfier.lock.#{Time.now.to_i}"

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Helper::Net

#delete_data, #get_data, #post_data, #put_data

Constructor Details

#initialize(p = {}) ⇒ BSig

Returns a new instance of BSig.



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# File 'lib/sfpagent/bsig.rb', line 15

def initialize(p={})
  @lock = Mutex.new
  @enabled = false
  @status = :stopped
end

Instance Attribute Details

#enabled ⇒ Object (readonly)

Returns the value of attribute enabled.



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# File 'lib/sfpagent/bsig.rb', line 13

def enabled
  @enabled
end

#mode ⇒ Object (readonly)

Returns the value of attribute mode.



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# File 'lib/sfpagent/bsig.rb', line 13

def mode
  @mode
end

#status ⇒ Object (readonly)

Returns the value of attribute status.



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# File 'lib/sfpagent/bsig.rb', line 13

def status
  @status
end

Instance Method Details

#achieve_local_goal(id, goal, operators, pi, mode) ⇒ Object

 @return

:no_flaw  => there is no goal-flaw
:failure  => there is a failure on achieving the goal
:pending  => the selected operator is being executed
:repaired => some goal-flaws have been repaired, but the goal may have other flaws

Parameters:

  • id —

    BSig’s id

  • goal —

    goal state

  • operators —

    an array of sorted (by ‘pi’) operators

  • pi —

    current priority index value

  • modethreadorthread ('main''satisfier') —

    ode ‘main’ thread or ‘satisfier’ thread



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# File 'lib/sfpagent/bsig.rb', line 149

def achieve_local_goal(id, goal, operators, pi, mode)
  parallel_achieve_local_goal(id, goal, operators, pi, mode)
end

#achieve_remote_agent_goal(agents, name, goal, id, pi, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 265

def achieve_remote_agent_goal(agents, name, goal, id, pi, mode)
  if agents.has_key?(name)
    return false if agents[name]['sfpAddress'].to_s == ''
    return false if not send_goal_to_agent(agents[name], id, goal, pi, name, mode)
  else
    return false if not verify_state_of_not_exist_agent(name, goal)
  end
  true
end

#achieve_remote_goal(id, goal, pi, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 240

def achieve_remote_goal(id, goal, pi, mode)
  if goal.length > 0
    agents = Sfp::Agent.get_agents
    status = []
    lock = Mutex.new
    agents_goal = split_goal_by_agent(goal)
    agents_goal.each do |agent_name,agent_goal|
      Thread.new {
        begin
          stat = achieve_remote_agent_goal(agents, agent_name, agent_goal, id, pi, mode)
          Sfp::Agent.logger.info "[#{mode}] remote goal => #{agent_name}: #{agent_goal.inspect} - #{stat}"
        rescue Exception => exp
          stat = false
          Sfp::Agent.logger.error "[#{mode}] remote goal => #{agent_name}: #{agent_goal.inspect} - #{stat} - #{exp}\n#{exp.backtrace.join("\n")}"
        end
        lock.synchronize { status << stat }
      }
    end
    wait_until? { status.length >= agents_goal.length }
    Sfp::Agent.logger.info "[#{mode}] achieve_remote_goal: #{status}"
    status.each { |stat| return false if !stat }
  end
  true
end

#can_repair?(operator, flaws) ⇒ Boolean

An operator can repair the flaws iff there is an effect that fixes the flaw

Returns:

  • (Boolean) 


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# File 'lib/sfpagent/bsig.rb', line 493

def can_repair?(operator, flaws)
  operator['effect'].each { |variable,value| return true if flaws[variable] == value }
  false
end

#check_not_created_agent(agent_name, goal) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 389

def check_not_created_agent(agent_name, goal)
  state = Sfp::Agent.get_state
  vms = {}
  Sfp::Agent.runtime.cloudfinder.clouds.each { |cloud|
    cloud.sub!(/^\$\./, '')
    cloud_ref = "$.#{Sfp::Agent.whoami?}.#{cloud}"
    ref = "#{cloud_ref}.vms"
    vms = state.at?(ref)
    vms.each { |name,status| vms[name] = {'created' => true} } if vms.is_a?(Hash)
  } if Sfp::Agent.runtime
  if not vms.has_key?(agent_name)
    state = {agent_name => {'created' => false, 'in_cloud' => nil}}
    goal.each { |var,val| return false if state.at?(var) != val }
    return true
  end
  false
end

#compute_flaws(goal, current) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 429

def compute_flaws(goal, current)
  return goal.clone if current.nil?
  flaws = {}
  goal.each { |var,val|
    current_value = current.at?(var)
    if current_value.is_a?(Sfp::Unknown)
      _, agent_name, _ = var.split('.', 3)
      if agent_name != Sfp::Agent.whoami?
        s = {agent_name => {'created' => false, 'in_cloud' => nil}}
        current_value = s.at?(var)
      end
    end
    if current_value.is_a?(Sfp::Undefined)
      flaws[var] = val if not val.is_a?(Sfp::Undefined)
    else
      current_value.sort! if current_value.is_a?(Array)
      flaws[var]= val if current_value != val
    end
  }
  flaws
end

#execute_model ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 57

def execute_model
  Sfp::Agent.logger.info "[main] Executing BSig model"

  previous_exec_status = exec_status = nil

  while @enabled
    begin

      wait_for_satisfier?

      bsig = Sfp::Agent.get_bsig
      if bsig.nil?
        exec_status = :no_bsig
        sleep SleepTime
      else
        bsig['operators'].sort! { |op1,op2| op1['pi'] <=> op2['pi'] }
        exec_status = achieve_local_goal(bsig['id'], bsig['goal'], bsig['operators'], 1, :main)
        if exec_status == :failure
          Sfp::Agent.logger.error "[main] Executing BSig model [Failed]"
          sleep SleepTime
        elsif exec_status == :no_flaw or exec_status == :pending
          sleep SleepTime
        end
      end

      if previous_exec_status != exec_status
        Sfp::Agent.logger.info "[main] BSig engine - status: " + exec_status.to_s
        previous_exec_status = exec_status
      end
    rescue Exception => e
      Sfp::Agent.logger.error "[main] Error on executing BSig model\n#{e}\n#{e.backtrace.join("\n")}"
      sleep SleepTime
    end
  end
end

#execute_operator(operator, id, operators, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 193

def execute_operator(operator, id, operators, mode)
  return :pending if not lock_operator(operator)

  status = :failure

  begin
    Sfp::Agent.logger.info "[#{mode}] Selected operator: #{operator['id']}:#{operator['name']}#{JSON.generate(operator['parameters'])}"

    next_pi = operator['pi'] + 1
    pre_local, pre_remote = split_preconditions(operator)

    # debugging
    Sfp::Agent.logger.info "[#{mode}] local-flaws: #{JSON.generate(pre_local)}, remote-flaws: #{JSON.generate(pre_remote)}"

    status = nil
    tries = MaxTries
    begin
      status = achieve_local_goal(id, pre_local, operators, next_pi, mode)
      if status == :no_flaw or status == :failure or not @enabled
        break
      elsif status == :pending
        sleep SleepTime
        tries += 1
      elsif status == :repaired
        tries = MaxTries
      end
      tries -= 1
    end until tries <= 0 and @enabled

    Sfp::Agent.logger.info "[#{mode}] achieve_local_goal => #{status}"

    if status != :no_flaw or
      not achieve_remote_goal(id, pre_remote, next_pi, mode) or
      not invoke(operator, mode)

      status = :failure
    end

  rescue Exception => exp
    Sfp::Agent.logger.info "[#{mode}] Execute #{operator['name']}{#{operator['parameters']}} [Error]"
    status = :failure
  end

  unlock_operator(operator) if not operator.nil?
  status
end

#get_current_state ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 407

def get_current_state
  state = Sfp::Agent.get_state
  fail "BSig engine cannot get current state" if state == false

  Sfp::Agent.runtime.cloudfinder.clouds.each { |cloud|
    cloud.sub!(/^\$\./, '')
    cloud_ref = "$.#{Sfp::Agent.whoami?}.#{cloud}"
    ref = "#{cloud_ref}.vms"
    vms = state.at?(ref)
    if vms.is_a?(Hash)
      vms.each { |name,status|
        state[name] = { 'created' => true,
                        'in_cloud' => cloud_ref,
                        'sfpAddress' => status['ip'],
                        'sfpPort' => Sfp::Agent::DefaultPort }
      }
    end
  } if Sfp::Agent.runtime

  state
end

#get_flaws ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 93

def get_flaws
  bsig = Sfp::Agent.get_bsig
  if bsig.nil?
    {}
  else
    current = get_current_state
    compute_flaws(bsig['goal'], current)
  end
end

#get_local_module_hash(name, modules_dir) ⇒ Object

return the list of Hash value of all modules



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# File 'lib/sfpagent/bsig.rb', line 666

def get_local_module_hash(name, modules_dir)
  module_dir = File.expand_path("#{modules_dir}/#{name}")
  if File.directory? module_dir
    if `which md5sum`.strip.length > 0
      return `find #{module_dir} -type f -exec md5sum {} + | awk '{print $1}' | sort | md5sum | awk '{print $1}'`.strip
    elsif `which md5`.strip.length > 0
      return `find #{module_dir} -type f -exec md5 {} + | awk '{print $4}' | sort | md5`.strip
    end
  end
  nil
end

#invoke(operator, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 538

def invoke(operator, mode)
  Sfp::Agent.logger.info "[#{mode}] Invoking #{operator['name']}{#{operator['parameters']}}"

  begin
    status = Sfp::Agent.execute_action(operator)
    if status
      if operator['name'] =~ /^\$(\.[a-zA-Z0-9_]+)*\.(create_vm)/
        postprocess_create_vm(operator)
      elsif operator['name'] =~ /^\$(\.[a-zA-Z0-9_]+)*\.(delete_vm)/
        postprocess_delete_vm(operator)
      end
    end
  rescue Exception => e
    Sfp::Agent.logger.error "Error in invoking operator #{operator['name']}{#{operator['parameters']}}\n#{e}\n#{e.backtrace.join("\n")}"
    return false
  end

  status
end

#lock_operator(operator) ⇒ Object

lock given operator by creating a lock file to avoid another thread executing the same operator

Parameters:

  • operator —

    operator to be locked



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# File 'lib/sfpagent/bsig.rb', line 340

def lock_operator(operator)
  @lock.synchronize {
    operator_lock_file = "#{Home}/operator.#{operator['id']}.#{operator['name']}.lock"
    return false if File.exist?(operator_lock_file)
    File.open(operator_lock_file, 'w') { |f| f.write('1') }
    return true
  }
end

#parallel_achieve_local_goal(id, goal, operators, pi, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 153

def parallel_achieve_local_goal(id, goal, operators, pi, mode)
  current = get_current_state
  flaws = compute_flaws(goal, current)

  return :no_flaw if flaws.length <= 0
  
  selected_operators = select_operators(flaws, operators, pi)
  return :failure if selected_operators == :failure
  
  Sfp::Agent.logger.info "total operators: #{selected_operators.length}"

  status = []
  lock = Mutex.new
  selected_operators.each do |operator|
    Thread.new {
      begin
        stat = execute_operator(operator, id, operators, mode)
        Sfp::Agent.logger.info "[#{mode}] Execute_operator: #{operator['name']}#{JSON.generate(operator['parameters'])} => #{stat}"
      rescue Exception => exp
        stat = :failure
        Sfp::Agent.logger.error "[#{mode}] Execute_operator: #{operator['name']}#{JSON.generate(operator['parameters'])} => #{stat} - #{exp}\n#{exp.backtrace.join("\n")}"
      end
      lock.synchronize { status << stat }
    }
  end
  wait_until? { (status.length >= selected_operators.length) }
  Sfp::Agent.logger.info "[#{mode}] exec status: #{status.inspect}"
  status.each { |stat|
    return :failure if stat == :failure
    return :pending if stat == :pending
  }
  :repaired
end

#postprocess_create_vm(operator) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 567

def postprocess_create_vm(operator)
  3.times do |i|
    refs = operator['name'].split('.')
    vms_ref = refs[0..-2].join('.') + '.vms'

    _, agent_name, _ = operator['parameters']['$.vm'].split('.', 3)

    Sfp::Agent.logger.info "Postprocess create VM #{agent_name}"

    # update proxy component's state
    state = Sfp::Agent.get_state
    return false if not state.is_a?(Hash)

    # get VM's address
    vms = state.at?(vms_ref)
    return false if !vms.is_a?(Hash) or !vms[agent_name].is_a?(Hash) or vms[agent_name]['ip'].to_s.strip == ''
    data = {agent_name => {'sfpAddress' => vms[agent_name]['ip'], 'sfpPort' => Sfp::Agent::DefaultPort}}

    # update agents database
    Sfp::Agent.set_agents(data)

    # get new agent's model and BSig model from cache database
    model = Sfp::Agent.get_cache_model(agent_name)
    model['model']['in_cloud'] = refs[0..-2].join('.')
    model['model']['sfpAddress'] = vms[agent_name]['ip']
    model['model']['sfpPort'] = Sfp::Agent::DefaultPort
    
    if not model.nil?
      address = data[agent_name]['sfpAddress']
      port = data[agent_name]['sfpPort']

      # wait until agent is running
      wait_until? {
        begin
          code, _ = get_data(address, port, '/')
          true
        rescue
          false
        end
      }

      # push required modules
      push_modules(model, address, port)

      # push agent database to new agent
      code, _ = put_data(address, port, '/agents', {'agents' => JSON.generate(Sfp::Agent.get_agents)})

      # push new agent's model
      code1, _ = put_data(address, port, '/model', {'model' => JSON.generate({agent_name => model['model']})})

      # push new agent's BSig model
      code2, _ = put_data(address, port, '/bsig', {'bsig' => JSON.generate(model['bsig'])}) if code == '200'

      return (code1 == '200' and code2 == '200')
    end
  end
  false
end

#postprocess_delete_vm(operator) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 558

def postprocess_delete_vm(operator)
  _, agent_name, _ = operator['parameters']['$.vm'].split('.', 3)

  Sfp::Agent.logger.info "Postprocess delete VM #{agent_name}"

  # update agents database (automatically broadcast to other agents)
  Sfp::Agent.set_agents({agent_name => nil})
end

#push_modules(agent_model, address, port) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 626

def push_modules(agent_model, address, port)
  name = agent_model['_self']
  finder = Sfp::Helper::SchemaCollector.new
  {:agent => agent_model}.accept(finder)
  schemata = finder.schemata.uniq.map { |x| x.sub(/^\$\./, '').downcase }

  modules_dir = Sfp::Agent.config[:modules_dir]
  install_module = File.expand_path('../../../bin/install_module', __FILE__)

  begin
    # get modules list
    code, body = get_data(address, port, '/modules')
    raise Exception, "Unable to get modules list from #{name}" if code.to_i != 200

    modules = JSON[body]
    list = ''
    schemata.each { |m|
      list += "#{m} " if File.exist?("#{modules_dir}/#{m}") and
                         (not modules.has_key?(m) or modules[m] != get_local_module_hash(m, modules_dir).to_s)
    }

    return true if list == ''

    if system("cd #{modules_dir}; #{install_module} #{address} #{port} #{list} 1>/dev/null 2>/tmp/install_module.error")
      Sfp::Agent.logger.info "Push modules #{list}to #{name} [OK]"
    else
      Sfp::Agent.logger.warn "Push modules #{list}to #{name} [Failed]"
    end

    return true

  rescue Exception => e
    Sfp::Agent.logger.warn "[WARN] Cannot push module to #{name} - #{e}"
  end

  false
end

#receive_goal_from_agent(id, goal, pi, client = '') ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 283

def receive_goal_from_agent(id, goal, pi, client='')
  register_satisfier_thread

  return false if not @enabled

  bsig = Sfp::Agent.get_bsig
  return false if bsig.nil? or id < bsig['id']

  bsig['operators'].sort! { |op1,op2| op1['pi'] <=> op2['pi'] }
  status = nil
  tries = MaxTries
  begin
    status = achieve_local_goal(bsig['id'], goal, bsig['operators'], pi, "satisfier[#{client}]")
    if status == :no_flaw or status == :failure or not @enabled
      break
    elsif status == :pending
      sleep SleepTime
      tries += 1
    elsif status == :repaired
      tries = MaxTries
    end
    tries -= 1
  end until tries <= 0

  return (status == :no_flaw)

ensure
  unregister_satisfier_thread
end

#register_satisfier_thread(mode = nil) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 313

def register_satisfier_thread(mode=nil)
  File.open(SatisfierLockFile, File::RDWR|File::CREAT, 0644) { |f|
    f.flock(File::LOCK_EX)
    value = (mode == :reset ? 0 : (f.read.to_i + 1))
    f.rewind
    f.write(value.to_s)
    f.flush
    f.truncate(f.pos)
  }
end

#select_operator(flaws, operators, pi) ⇒ Object

Returns an operator that can repair the flaws.

Parameters:

  • flaws —

    a map of flaws (variable-value) that should be repaired

  • operators —

    a sorted-list of operators (sorted by ‘pi’)

  • pi —

    minimum priority-index value

Returns:

  • an operator that can repair the flaws



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# File 'lib/sfpagent/bsig.rb', line 483

def select_operator(flaws, operators, pi)
  operators.each do |op|
    next if op['pi'] < pi
    return op if can_repair?(op, flaws)
  end
  nil
end

#select_operators(flaws, operators, pi) ⇒ Object

Returns a list of applicable operators, or symbol :failure if all flaws cannot be repaired by available operators.

Parameters:

  • flaws —

    a map of flaws (variable-value) that should be repaired

  • operators —

    a sorted-list of operators (sorted by ‘pi’)

  • pi —

    minimum priority-index value

Returns:

  • a list of applicable operators, or symbol :failure if all flaws cannot be repaired by available operators



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# File 'lib/sfpagent/bsig.rb', line 458

def select_operators(flaws, operators, pi)
  selected_operators = []
  repaired = {}
  operators.each do |op|
    next if op['pi'] < pi
    if can_repair?(op, flaws) and                     # can the operator repair the flaws?
       not threat_operators?(op, selected_operators)  # does the operator threat other selected operators?
      selected_operators << op
      op['effect'].each { |var,val| repaired[var] = val if flaws[var] == val }
    end
    break if repaired.length >= flaws.length
  end
  if selected_operators.length <= 0 #repaired.length < flaws.length
    Sfp::Agent.logger.error "No flaws can be repaired - pi=#{pi}\nflaws: #{flaws.inspect}"
    return :failure
  end
  selected_operators
end

#send_goal_to_agent(agent, id, goal, pi, agent_name, mode) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 371

def send_goal_to_agent(agent, id, goal, pi, agent_name, mode)
  begin
    data = {
      'id' => id,
      'goal' => JSON.generate(goal),
      'pi' => pi
    }
    Sfp::Agent.logger.info "[#{mode}] Request goal to #{agent_name}@#{agent['sfpAddress']}:#{agent['sfpPort']} [WAIT]"
    code, _ = put_data(agent['sfpAddress'], agent['sfpPort'], SatisfierPath, data)
    Sfp::Agent.logger.info "[#{mode}] Request goal to #{agent_name}@#{agent['sfpAddress']}:#{agent['sfpPort']} #{code}"
    (code == '200')
  rescue Exception => exp
    Sfp::Agent.logger.info "[#{mode}] Request goal to #{agent_name} - error: #{exp}\n#{exp.bracktrace.join("\n")}"
    return true if check_not_created_agent(agent_name, goal)
    false
  end
end

#sequential_achieve_local_goal(id, goal, operators, pi, mode) ⇒ Object

 @return

:no_flaw  => there is no goal-flaw
:failure  => there is a failure on achieving the goal
:pending  => the selected operator is being executed
:repaired => some goal-flaws have been repaired, but the goal may have other flaws

Parameters:

  • id —

    BSig’s id

  • goal —

    goal state

  • operators —

    an array of sorted (by ‘pi’) operators

  • pi —

    current priority index value

  • modethreadorthread ('main''satisfier') —

    ode ‘main’ thread or ‘satisfier’ thread



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# File 'lib/sfpagent/bsig.rb', line 124

def sequential_achieve_local_goal(id, goal, operators, pi, mode)
  operator = nil

  current = get_current_state
  flaws = compute_flaws(goal, current)
  return :no_flaw if flaws.length <= 0

  operator = select_operator(flaws, operators, pi)
  return :failure if operator.nil?
  
  execute_operator(operator, id, operators, mode)
end

#split_goal_by_agent(goal) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 361

def split_goal_by_agent(goal)
  agent_goal = {}
  goal.each { |var,val|
    _, agent_name, _ = var.split('.', 3)
    agent_goal[agent_name] = {} if not agent_goal.has_key?(agent_name)
    agent_goal[agent_name][var] = val
  }
  agent_goal
end

#split_preconditions(operator) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 521

def split_preconditions(operator)
  local = {}
  remote = {}
  if not operator.nil?
    myself = Sfp::Agent.whoami?
    operator['condition'].each { |var,val|
      _, agent_name, _ = var.split('.', 3)
      if agent_name == myself
        local[var] = val
      else
        remote[var] = val
      end
    }
  end
  [local, remote]
end

#start ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 25

def start
  @enabled = true
  @lock.synchronize {
    return if @status == :running
    @status = :running
  }

  Thread.new {
    begin
      register_satisfier_thread(:reset)

      system("rm -f #{Home}/operator.*.lock")
      system("rm -f #{Home}/bsig.satisfier.lock.*")

      Sfp::Agent.logger.info "[main] BSig engine is running."

      puts "BSig Engine is running with PID #{$$}"
      File.open(Sfp::Agent::BSigPIDFile, 'w') { |f| f.write($$.to_s) }

      self.execute_model

      File.delete(SatisfierLockFile) if File.exist?(SatisfierLockFile)
      Sfp::Agent.logger.info "[main] BSig engine has stopped."

    rescue Exception => exp
      Sfp::Agent.logger.error "Cannot start BSig engine => #{exp}\n#{exp.backtrace.join("\n")}"
    end
    
    @status = :stopped
  }
end

#stop ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 21

def stop
  @enabled = false
end

#threat?(operator1, operator2) ⇒ Boolean

 Return true if operator1 threats operator2: there is an effect’s variable of operator1 is in condition’s or effect’s variable of operator2

Returns:

  • (Boolean) 


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# File 'lib/sfpagent/bsig.rb', line 513

def threat?(operator1, operator2)
  operator1['effect'].each_key do |variable1|
    return true if operator2['condition'].keys.include?(variable1) or
                   operator2['effect'].keys.include?(variable1)
  end
  false
end

#threat_operators?(operator, operators) ⇒ Boolean

Check if an operator threats a set of operators.

Parameters:

  • operator —

    operator to be checked

  • operators —

    a set of operators

Returns:

  • (Boolean) 


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# File 'lib/sfpagent/bsig.rb', line 503

def threat_operators?(operator, operators)
  operators.each do |op|
    return true if threat?(operator, op)
  end
  false
end

#unlock_operator(operator) ⇒ Object

unlock given operator by deleting lock file in order to allow another thread executing the operator

Parameters:

  • operator —

    operator to be unlocked



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# File 'lib/sfpagent/bsig.rb', line 354

def unlock_operator(operator)
  @lock.synchronize {
    operator_lock_file = "#{Home}/operator.#{operator['id']}.#{operator['name']}.lock"
    File.delete(operator_lock_file) if File.exist?(operator_lock_file)
  }
end

#unregister_satisfier_thread ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 324

def unregister_satisfier_thread
  File.open(SatisfierLockFile, File::RDWR|File::CREAT, 0644) { |f|
    f.flock(File::LOCK_EX)
    value = f.read.to_i - 1
    f.rewind
    f.write(value.to_s)
    f.flush
    f.truncate(f.pos)
  }
end

#verify_state_of_not_exist_agent(name, goal) ⇒ Object 



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# File 'lib/sfpagent/bsig.rb', line 275

def verify_state_of_not_exist_agent(name, goal)
  state = { name => { 'created' => false } }
  goal.each { |var,val|
    return false if state.at?(var) != val
  }
  true
end

#wait_for_satisfier? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/sfpagent/bsig.rb', line 103

def wait_for_satisfier?
  total_satisfier = 1
  loop do
    total_satisfier = (File.exist?(SatisfierLockFile) ? File.read(SatisfierLockFile).to_i : 0)
    return if total_satisfier <= 0 or not @enabled
    sleep 1
  end
end

#wait_until? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/sfpagent/bsig.rb', line 187

def wait_until?
  until yield do
    sleep 1
  end
end