node.rb in arborist-0.1.0

- old
+ new

@@ -42,15 +42,23 @@
 		description
 		dependencies
 		status_changed
 		last_contacted
 		ack
-		error
+		errors
 		quieted_reasons
 		config
 	]
 
+	# Node states that are unreachable by default.
+	UNREACHABLE_STATES = %w[
+		down
+		disabled
+		quieted
+	]
+
+
 	autoload :Root, 'arborist/node/root'
 	autoload :Ack, 'arborist/node/ack'
 
 
 	# Log via the Arborist logger
@@ -112,12 +120,12 @@
 			:disabled,
 			:quieted
 
 		event :update do
 			transition [:up, :unknown] => :disabled, if: :ack_set?
-			transition [:down, :unknown, :acked] => :up, if: :last_contact_successful?
-			transition [:up, :unknown] => :down, unless: :last_contact_successful?
+			transition [:down, :unknown, :acked] => :up, unless: :has_errors?
+			transition [:up, :unknown, :acked] => :down, if: :has_errors?
 			transition :down => :acked, if: :ack_set?
 			transition :disabled => :unknown, unless: :ack_set?
 		end
 
 		event :handle_event do
@@ -272,11 +280,11 @@
 		# Primary state
 		@status          = 'unknown'
 		@status_changed  = Time.at( 0 )
 
 		# Attributes that govern state
-		@error           = nil
+		@errors          = {}
 		@ack             = nil
 		@last_contacted  = Time.at( 0 )
 		@quieted_reasons = {}
 
 		# Event-handling
@@ -319,12 +327,13 @@
 	##
 	# The Time the node's status last changed.
 	attr_accessor :status_changed
 
 	##
-	# The last error encountered by a monitor attempting to update this node.
-	attr_accessor :error
+	# The Hash of last errors encountered by a monitor attempting to update this
+	# node, keyed by the monitor's `key`.
+	attr_accessor :errors
 
 	##
 	# The acknowledgement currently in effect. Should be an instance of Arborist::Node::ACK
 	attr_accessor :ack
 
@@ -476,17 +485,21 @@
 
 
 	### Update specified +properties+ for the node.
 	def update( new_properties )
 		new_properties = stringify_keys( new_properties )
-		self.log.debug "Updated: %p" % [ new_properties ]
+		monitor_key = new_properties[ '_monitor_key' ] || '_'
 
+		self.log.debug "Updated via a %s monitor: %p" % [ monitor_key, new_properties ]
 		self.last_contacted = Time.now
+
 		if new_properties.key?( 'ack' )
 			self.ack = new_properties.delete( 'ack' )
+		elsif new_properties['error']
+			self.errors[ monitor_key ] = new_properties.delete( 'error' )
 		else
-			self.error = new_properties.delete( 'error' )
+			self.errors.delete( monitor_key )
 		end
 
 		self.properties.merge!( new_properties, &self.method(:merge_and_record_delta) )
 		compact_hash( self.properties )
 
@@ -585,10 +598,12 @@
 			when 'status'
 				self.status == val
 			when 'type'
 				self.log.debug "Checking node type %p against %p" % [ self.type, val ]
 				self.type == val
+			when 'parent'
+				self.parent == val
 			when 'tag' then @tags.include?( val.to_s )
 			when 'tags' then Array(val).all? {|tag| @tags.include?(tag) }
 			when 'identifier' then @identifier == val
 			when 'config'
 				val.all? {|ikey, ival| hash_matches(@config, ikey, ival) }
@@ -678,11 +693,12 @@
 			self.log.debug "No handler for a %s event!" % [ event.type ]
 		end
 
 		super # to state-machine
 
-		return self.collect_events
+		self.publish_events( event, *self.pending_update_events )
+		self.collect_events
 	end
 
 
 	### Returns +true+ if this node's dependencies are not met.
 	def dependencies_down?
@@ -790,10 +806,24 @@
 	def operational?
 		return self.identifier.start_with?( '_' )
 	end
 
 
+	### Returns +true+ if the node's status indicates it shouldn't be
+	### included by default when traversing nodes.
+	def unreachable?
+		return UNREACHABLE_STATES.include?( self.status )
+	end
+
+
+	### Returns +true+ if the node's status indicates it is included by
+	### default when traversing nodes.
+	def reachable?
+		return !self.unreachable?
+	end
+
+
 	### Register the specified +node+ as a child of this node, replacing any existing
 	### node with the same identifier.
 	def add_child( node )
 		self.log.debug "Adding node %p as a child. Parent = %p" % [ node, node.parent ]
 		raise "%p is not a child of %p" % [ node, self ] if
@@ -878,11 +908,11 @@
 		@status          = old_node.status
 		@properties      = old_node.properties.dup
 		@ack             = old_node.ack.dup if old_node.ack
 		@last_contacted  = old_node.last_contacted
 		@status_changed  = old_node.status_changed
-		@error           = old_node.error
+		@errors          = old_node.errors
 		@quieted_reasons = old_node.quieted_reasons
 
 		# Only merge in downed dependencies.
 		old_node.dependencies.each_downed do |identifier, time|
 			@dependencies.mark_down( identifier, time )
@@ -902,11 +932,11 @@
 			status: self.status,
 			properties: self.properties.dup,
 			ack: self.ack ? self.ack.to_h : nil,
 			last_contacted: self.last_contacted ? self.last_contacted.iso8601 : nil,
 			status_changed: self.status_changed ? self.status_changed.iso8601 : nil,
-			error: self.error,
+			errors: self.errors,
 			dependencies: self.dependencies.to_h,
 			quieted_reasons: self.quieted_reasons,
 		}
 	end
 
@@ -932,11 +962,11 @@
 
 		@status          = hash[:status]
 		@status_changed  = Time.parse( hash[:status_changed] )
 		@ack             = Arborist::Node::Ack.from_hash( hash[:ack] ) if hash[:ack]
 
-		@error           = hash[:error]
+		@errors          = hash[:errors]
 		@properties      = hash[:properties] || {}
 		@last_contacted  = Time.parse( hash[:last_contacted] )
 		@quieted_reasons = hash[:quieted_reasons] || {}
 		self.log.debug "Deps are: %p" % [ hash[:dependencies] ]
 		@dependencies    = hash[:dependencies]
@@ -986,17 +1016,27 @@
 	end
 
 
 	### State machine guard predicate -- Returns +true+ if the last time the node
 	### was monitored resulted in an update.
-	def last_contact_successful?
-		self.log.debug "Checking to see if last contact was successful (it %s)" %
-			[ self.error ? "wasn't" : "was" ]
-		return !self.error
+	def has_errors?
+		has_errors = ! self.errors.empty?
+		self.log.debug "Checking to see if last contact cleared remaining errors (it %s)" %
+			[ has_errors ? "did not" : "did" ]
+		self.log.debug "Errors are: %p" % [ self.errors ]
+		return has_errors
 	end
 
 
+	### Return a string describing the errors that are set on the node.
+	def errors_description
+		return "No errors" if self.errors.empty?
+		return self.errors.map do |key, msg|
+			"%s: %s" % [ key, msg ]
+		end.join( '; ' )
+	end
+
 	#
 	# :section: State Callbacks
 	#
 
 	### Log every status transition
@@ -1033,18 +1073,18 @@
 	end
 
 
 	### Callback for when a node goes from down to up
 	def on_node_up( transition )
-		self.error = nil
+		self.errors.clear
 		self.log.warn "%s is %s" % [ self.identifier, self.status_description ]
 	end
 
 
 	### Callback for when a node goes from up to down
 	def on_node_down( transition )
 		self.log.error "%s is %s" % [ self.identifier, self.status_description ]
-		self.update_delta[ 'error' ] = [ nil, self.error ]
+		self.update_delta[ 'errors' ] = [ nil, self.errors_description ]
 	end
 
 
 	### Callback for when a node goes from up to disabled
 	def on_node_disabled( transition )