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.backtrace.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