BF+RF: pyinotify refreshes watcher upon CREATE, unified/simplified *(add|del)LogPath among *Filters

* all of the *Filters had too much of common logic in their *LogPath
  methods, which is now handled by FileFilter and derived classes only
  add custom actions in corresponding _(add|del)LogPath methods

pyinotify:

* upon CREATE event:
  - unknown files should not be handled at all
  - "watcher" for the monitored files should be recreated.
    Lead to adding _(add|del)FileWatcher helper methods
* callback now obtains full event to judge what to do

server/filter.py

@@ -395,8 +395,19 @@ class FileFilter(Filter):
 	# @param path log file path
 
 	def addLogPath(self, path, tail = False):
-		container = FileContainer(path, tail)
-		self.__logPath.append(container)
+		if self.containsLogPath(path):
+			logSys.error(path + " already exists")
+		else:
+			container = FileContainer(path, tail)
+			self.__logPath.append(container)
+			logSys.info("Added logfile = %s" % path)
+			self._addLogPath(path)			# backend specific
+
+	def _addLogPath(self, path):
+		# nothing to do by default
+		# to be overriden by backends
+		pass
+
 
 	##
 	# Delete a log path
@@ -407,8 +418,15 @@ class FileFilter(Filter):
 		for log in self.__logPath:
 			if log.getFileName() == path:
 				self.__logPath.remove(log)
+				logSys.info("Removed logfile = %s" % path)
+				self._delLogPath(path)
 				return
 
+	def _delLogPath(self, path):
+		# nothing to do by default
+		# to be overriden by backends
+		pass
+
 	##
 	# Get the log file path
 	#

server/filtergamin.py

@@ -72,27 +72,17 @@ class FilterGamin(FileFilter):
 	#
 	# @param path log file path
 
-	def addLogPath(self, path, tail = False):
-		if self.containsLogPath(path):
-			logSys.error(path + " already exists")
-		else:
-			self.monitor.watch_file(path, self.callback)
-			FileFilter.addLogPath(self, path, tail)
-			logSys.info("Added logfile = %s" % path)			
-	
+	def _addLogPath(self, path):
+		self.monitor.watch_file(path, self.callback)
+
 	##
 	# Delete a log path
 	#
 	# @param path the log file to delete
-	
+
 	def delLogPath(self, path):
-		if not self.containsLogPath(path):
-			logSys.error(path + " is not monitored")
-		else:
-			self.monitor.stop_watch(path)
-			FileFilter.delLogPath(self, path)
-			logSys.info("Removed logfile = %s" % path)
-		
+		self.monitor.stop_watch(path)
+
 	##
 	# Main loop.
 	#

server/filterpoll.py

@@ -63,28 +63,18 @@ class FilterPoll(FileFilter):
 	#
 	# @param path log file path
 
-	def addLogPath(self, path, tail = False):
-		if self.containsLogPath(path):
-			logSys.error(path + " already exists")
-		else:
-			self.__lastModTime[path] = 0
-			self.__file404Cnt[path] = 0
-			FileFilter.addLogPath(self, path, tail)
-			logSys.info("Added logfile = %s" % path)
+	def _addLogPath(self, path):
+		self.__lastModTime[path] = 0
+		self.__file404Cnt[path] = 0
 
 	##
 	# Delete a log path
 	#
 	# @param path the log file to delete
 
-	def delLogPath(self, path):
-		if not self.containsLogPath(path):
-			logSys.error(path + " is not monitored")
-		else:
-			del self.__lastModTime[path]
-			del self.__file404Cnt[path]
-			FileFilter.delLogPath(self, path)
-			logSys.info("Removed logfile = %s" % path)
+	def _delLogPath(self, path):
+		del self.__lastModTime[path]
+		del self.__file404Cnt[path]
 
 	##
 	# Main loop.

server/filterpyinotify.py

@@ -57,7 +57,29 @@ class FilterPyinotify(FileFilter):
 		logSys.debug("Created FilterPyinotify")
 
 
-	def callback(self, path):
+	def callback(self, event):
+		path = event.pathname
+		if event.mask == pyinotify.IN_CREATE:
+			# check if that is a file we care about
+			if not path in self.__watches:
+				logSys.debug("Ignoring creation of %s we do not monitor" % path)
+				return
+			else:
+				# we need to substitute the watcher with a new one, so first
+				# remove old one
+				self._delFileWatcher(path)
+				# place a new one
+				self._addFileWatcher(path)
+
+		self._process_file(path)
+
+
+	def _process_file(self, path):
+		"""Process a given file
+
+		TODO -- RF:
+		this is a common logic and must be shared/provided by FileFilter
+		"""
 		self.getFailures(path)
 		try:
 			while True:
@@ -68,57 +90,58 @@ class FilterPyinotify(FileFilter):
 		self.dateDetector.sortTemplate()
 		self.__modified = False
 
+
+	def _addFileWatcher(self, path):
+		wd = self.__monitor.add_watch(path, pyinotify.IN_MODIFY)
+		self.__watches.update(wd)
+		logSys.debug("Added file watcher for %s" % path)
+		# process the file since we did get even 
+		self._process_file(path)
+
+
+	def _delFileWatcher(self, path):
+		wdInt = self.__watches[path]
+		wd = self.__monitor.rm_watch(wdInt)
+		if wd[wdInt]:
+			del self.__watches[path]
+			logSys.debug("Removed file watcher for %s" % path)
+			return True
+		else:
+			return False
+
 	##
 	# Add a log file path
 	#
 	# @param path log file path
 
-	def addLogPath(self, path, tail=False):
-		if self.containsLogPath(path):
-			logSys.error(path + " already exists")
-		else:
-			wd = self.__monitor.add_watch(path, pyinotify.IN_MODIFY)
-			self.__watches.update(wd)
+	def _addLogPath(self, path):
+		path_dir = dirname(path)
+		if not (path_dir in self.__watches):
+			# we need to watch also  the directory for IN_CREATE
+			self.__watches.update(
+				self.__monitor.add_watch(path_dir, pyinotify.IN_CREATE))
+			logSys.debug("Added monitor for the parent directory %s" % path_dir)
 
-			FileFilter.addLogPath(self, path, tail)
-			logSys.info("Added logfile = %s" % path)
+		self._addFileWatcher(path)
 
-			path_dir = dirname(path)
-			if not (path_dir in self.__watches):
-				# we need to watch also  the directory for IN_CREATE
-				self.__watches.update(
-					self.__monitor.add_watch(path_dir, pyinotify.IN_CREATE))
-				logSys.debug("Monitor also parent directory %s" % path_dir)
-
-		# sniff the file
-		self.callback(path)
 
     ##
 	# Delete a log path
 	#
 	# @param path the log file to delete
 
-	def delLogPath(self, path):
-		if not self.containsLogPath(path):
-			logSys.error(path + " is not monitored")
-		else:
-			wdInt = self.__watches[path]
-			wd = self.__monitor.rm_watch(wdInt)
-			if wd[wdInt]:
-				del self.__watches[path]
-				FileFilter.delLogPath(self, path)
-				logSys.info("Removed logfile = %s" % path)
-			else:
-				logSys.error("Failed to remove watch on path: %s", path)
+	def _delLogPath(self, path):
+		if not self._delFileWatcher(path):
+			logSys.error("Failed to remove watch on path: %s", path)
 
-			path_dir = dirname(path)
-			if not len([k for k in self.__watches
-						if k.startswith(path_dir + pathsep)]):
-				# Remove watches for the directory
-				# since there is no other monitored file under this directory
-				wdInt = self.__watches.pop(path_dir)
-				_ = self.__monitor.rm_watch(wdInt)
-				logSys.debug("Remove monitor for the parent directory %s" % path_dir)
+		path_dir = dirname(path)
+		if not len([k for k in self.__watches
+					if k.startswith(path_dir + pathsep)]):
+			# Remove watches for the directory
+			# since there is no other monitored file under this directory
+			wdInt = self.__watches.pop(path_dir)
+			_ = self.__monitor.rm_watch(wdInt)
+			logSys.debug("Removed monitor for the parent directory %s" % path_dir)
 
 
 	##
@@ -169,4 +192,4 @@ class ProcessPyinotify(pyinotify.ProcessEvent):
 	# just need default, since using mask on watch to limit events
 	def process_default(self, event):
 		logSys.debug("Callback for Event: %s" % event)
-		self.__FileFilter.callback(event.pathname)
+		self.__FileFilter.callback(event)