Added inotify filemonitor driver

Moved list of files to ignore into config

5 files changed, 379 insertions, 0 deletions

diff --git a/src/lib/Bcfg2/Server/FileMonitor/Fam.py b/src/lib/Bcfg2/Server/FileMonitor/Fam.py
new file mode 100644
index 000000000..1a00fffa0
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/Fam.py
@@ -0,0 +1,82 @@
+""" Fam provides FAM support for file alteration events """
+
+import os
+import _fam
+import stat
+import logging
+from time import time
+from Bcfg2.Server.FileMonitor import FileMonitor
+
+logger = logging.getLogger(__name__)
+
+class Fam(FileMonitor):
+    __priority__ = 90
+
+    def __init__(self, ignore=None, debug=False):
+        FileMonitor.__init__(self, ignore=ignore, debug=debug)
+        self.fm = _fam.open()
+        self.users = {}
+
+    def fileno(self):
+        """Return fam file handle number."""
+        return self.fm.fileno()
+
+    def handle_event_set(self, _):
+        self.Service()
+
+    def handle_events_in_interval(self, interval):
+        now = time()
+        while (time() - now) < interval:
+            if self.Service():
+                now = time()
+
+    def AddMonitor(self, path, obj):
+        """Add a monitor to path, installing a callback to obj.HandleEvent."""
+        mode = os.stat(path)[stat.ST_MODE]
+        if stat.S_ISDIR(mode):
+            handle = self.fm.monitorDirectory(path, None)
+        else:
+            handle = self.fm.monitorFile(path, None)
+        self.handles[handle.requestID()] = handle
+        if obj != None:
+            self.users[handle.requestID()] = obj
+        return handle.requestID()
+
+    def Service(self, interval=0.50):
+        """Handle all fam work."""
+        count = 0
+        collapsed = 0
+        rawevents = []
+        start = time()
+        now = time()
+        while (time() - now) < interval:
+            if self.fm.pending():
+                while self.fm.pending():
+                    count += 1
+                    rawevents.append(self.fm.nextEvent())
+                now = time()
+        unique = []
+        bookkeeping = []
+        for event in rawevents:
+            if self.should_ignore(event):
+                continue
+            if event.code2str() != 'changed':
+                # process all non-change events
+                unique.append(event)
+            else:
+                if (event.filename, event.requestID) not in bookkeeping:
+                    bookkeeping.append((event.filename, event.requestID))
+                    unique.append(event)
+                else:
+                    collapsed += 1
+        for event in unique:
+            if event.requestID in self.users:
+                try:
+                    self.users[event.requestID].HandleEvent(event)
+                except:
+                    logger.error("Handling event for file %s" % event.filename,
+                                 exc_info=1)
+        end = time()
+        logger.info("Processed %s fam events in %03.03f seconds. %s coalesced" %
+                    (count, (end - start), collapsed))
+        return count
diff --git a/src/lib/Bcfg2/Server/FileMonitor/Gamin.py b/src/lib/Bcfg2/Server/FileMonitor/Gamin.py
new file mode 100644
index 000000000..60f80c9c3
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/Gamin.py
@@ -0,0 +1,64 @@
+""" Gamin driver for file alteration events """
+
+import os
+import stat
+import logging
+from gamin import WatchMonitor, GAMCreated, GAMExists, GAMEndExist, \
+    GAMChanged, GAMDeleted
+from Bcfg2.Server.FileMonitor import Event, FileMonitor
+
+logger = logging.getLogger(__name__)
+
+class GaminEvent(Event):
+    """
+    This class provides an event analogous to
+    python-fam events based on gamin sources.
+    """
+    action_map = {GAMCreated: 'created', GAMExists: 'exists',
+                  GAMChanged: 'changed', GAMDeleted: 'deleted',
+                  GAMEndExist: 'endExist'}
+
+    def __init__(self, request_id, filename, code):
+        Event.__init__(self, request_id, filename, code)
+        if code in self.action_map:
+            self.action = self.action_map[code]
+
+class Gamin(FileMonitor):
+    __priority__ = 10
+
+    def __init__(self, ignore=None, debug=False):
+        FileMonitor.__init__(self, ignore=ignore, debug=debug)
+        self.mon = WatchMonitor()
+        self.counter = 0
+
+    def fileno(self):
+        return self.mon.get_fd()
+
+    def queue(self, path, action, request_id):
+        """queue up the event for later handling"""
+        self.events.append(GaminEvent(request_id, path, action))
+
+    def AddMonitor(self, path, obj):
+        """Add a monitor to path, installing a callback to obj."""
+        handle = self.counter
+        self.counter += 1
+        mode = os.stat(path)[stat.ST_MODE]
+
+        # Flush queued gamin events
+        while self.mon.event_pending():
+            self.mon.handle_one_event()
+
+        if stat.S_ISDIR(mode):
+            self.mon.watch_directory(path, self.queue, handle)
+        else:
+            self.mon.watch_file(path, self.queue, handle)
+        self.handles[handle] = obj
+        return handle
+
+    def pending(self):
+        return FileMonitor.pending(self) or self.mon.event_pending()
+
+    def get_event(self):
+        if self.mon.event_pending():
+            self.mon.handle_one_event()
+        return FileMonitor.get_event(self)
diff --git a/src/lib/Bcfg2/Server/FileMonitor/Inotify.py b/src/lib/Bcfg2/Server/FileMonitor/Inotify.py
new file mode 100644
index 000000000..9743d868d
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/Inotify.py
@@ -0,0 +1,60 @@
+""" Inotify driver for file alteration events """
+
+import os
+import stat
+import logging
+import operator
+import pyinotify
+from Bcfg2.Server.FileMonitor import FileMonitor, Event
+
+logger = logging.getLogger(__name__)
+
+class InotifyEvent(Event):
+    action_map = {pyinotify.IN_CREATE: 'created',
+                  pyinotify.IN_DELETE: 'deleted',
+                  pyinotify.IN_MODIFY: 'changed'}
+
+    def __init__(self, event):
+        Event.__init__(self, event.wd, event.pathname, event.mask)
+        if event.mask in self.action_map:
+            self.action = self.action_map[event.mask]
+
+
+class Inotify(FileMonitor, pyinotify.ProcessEvent):
+    __priority__ = 1
+    mask = pyinotify.IN_CREATE | pyinotify.IN_DELETE | pyinotify.IN_MODIFY
+
+    def __init__(self, ignore=None, debug=False):
+        FileMonitor.__init__(self, ignore=ignore, debug=debug)
+        self.wm = pyinotify.WatchManager()
+        self.notifier = pyinotify.ThreadedNotifier(self.wm, self)
+        self.notifier.start()
+
+    def fileno(self):
+        return self.wm.get_fd()
+
+    def process_default(self, event):
+        self.events.append(InotifyEvent(event))
+
+    def AddMonitor(self, path, obj):
+        res = self.wm.add_watch(path, self.mask, quiet=False)
+        if not res:
+            # if we didn't get a return, but we also didn't get an
+            # exception, we're already watching this directory, so we
+            # need to find the watch descriptor for it
+            for wd, watch in self.wm.watches.items():
+                if watch.path == path:
+                    wd = watch.wd
+        else:
+            wd = res[path]
+        self.handles[wd] = obj
+        self.events.append(Event(wd, path, "exists"))
+
+        mode = os.stat(path)[stat.ST_MODE]
+        if stat.S_ISDIR(mode):
+            for wname in os.listdir(path):
+                self.events.append(Event(wd, wname, "exists"))
+        return wd
+
+    def shutdown(self):
+        self.notifier.stop()
diff --git a/src/lib/Bcfg2/Server/FileMonitor/Pseudo.py b/src/lib/Bcfg2/Server/FileMonitor/Pseudo.py
new file mode 100644
index 000000000..4c2d90250
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/Pseudo.py
@@ -0,0 +1,30 @@
+""" Pseudo provides static monitor support for file alteration events """
+
+import os
+import stat
+import logging
+from Bcfg2.Server.FileMonitor import FileMonitor, Event
+
+logger = logging.getLogger(__name__)
+
+class Pseudo(FileMonitor):
+    __priority__ = 99
+
+    def AddMonitor(self, path, obj):
+        """add a monitor to path, installing a callback to obj.HandleEvent"""
+        handleID = len(list(self.handles.keys()))
+        mode = os.stat(path)[stat.ST_MODE]
+        handle = Event(handleID, path, 'exists')
+        if stat.S_ISDIR(mode):
+            dirList = os.listdir(path)
+            self.pending_events.append(handle)
+            for includedFile in dirList:
+                self.pending_events.append(Event(handleID,
+                                                 includedFile,
+                                                 'exists'))
+            self.pending_events.append(Event(handleID, path, 'endExist'))
+        else:
+            self.pending_events.append(Event(handleID, path, 'exists'))
+        if obj != None:
+            self.handles[handleID] = obj
+        return handleID
diff --git a/src/lib/Bcfg2/Server/FileMonitor/__init__.py b/src/lib/Bcfg2/Server/FileMonitor/__init__.py
new file mode 100644
index 000000000..40c3253b9
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/__init__.py
@@ -0,0 +1,143 @@
+"""Bcfg2.Server.FileMonitor provides the support for monitoring files."""
+
+import os
+import fnmatch
+import logging
+import pkgutil
+from time import sleep, time
+
+logger = logging.getLogger(__name__)
+
+class Event(object):
+    def __init__(self, request_id, filename, code):
+        self.requestID = request_id
+        self.filename = filename
+        self.action = code
+
+    def code2str(self):
+        """return static code for event"""
+        return self.action
+
+    def __str__(self):
+        return "%s: %s %s" % (self.__class__.__name__,
+                              self.filename, self.action)
+
+    def __repr__(self):
+        return "%s (request ID %s)" % (str(self), self.requestID)
+
+
+class FileMonitor(object):
+    """File Monitor baseclass."""
+    def __init__(self, ignore=None, debug=False):
+        object.__init__(self)
+        self.debug = debug
+        self.handles = dict()
+        self.events = []
+        if ignore is None:
+            ignore = []
+        self.ignore = ignore
+
+    def __str__(self):
+        return "%s: %s" % (__name__, self.__class__.__name__)
+
+    def __repr__(self):
+        if self.pending():
+            events = "has"
+        else:
+            events = "no"
+        return "%s (%s events, fd %s)" % (str(self), events, self.fileno)
+
+    def should_ignore(self, event):
+        for pattern in self.ignore:
+            if (fnmatch.fnmatch(event.filename, pattern) or 
+                fnmatch.fnmatch(os.path.split(event.filename)[-1], pattern)):
+                if self.debug:
+                    logger.info("Ignoring %s" % event)
+                return True
+        return False
+
+    def pending(self):
+        return bool(self.events)
+
+    def get_event(self):
+        return self.events.pop(0)
+
+    def fileno(self):
+        return 0
+
+    def handle_one_event(self, event):
+        if self.should_ignore(event):
+            return
+        if event.requestID not in self.handles:
+            logger.info("Got event for unexpected id %s, file %s" %
+                        (event.requestID, event.filename))
+            return
+        if self.debug:
+            logger.info("Dispatching event %s %s to obj %s" %
+                        (event.code2str(), event.filename,
+                         self.handles[event.requestID]))
+        try:
+            self.handles[event.requestID].HandleEvent(event)
+        except:
+            logger.error("Error in handling of event for %s" %
+                         event.filename, exc_info=1)
+
+    def handle_event_set(self, lock=None):
+        count = 1
+        event = self.get_event()
+        start = time()
+        if lock:
+            lock.acquire()
+        try:
+            self.handle_one_event(event)
+            while self.pending():
+                self.handle_one_event(self.get_event())
+                count += 1
+        except:
+            pass
+        if lock:
+            lock.release()
+        end = time()
+        logger.info("Handled %d events in %.03fs" % (count, (end - start)))
+
+    def handle_events_in_interval(self, interval):
+        end = time() + interval
+        while time() < end:
+            if self.pending():
+                self.handle_event_set()
+                end = time() + interval
+            else:
+                sleep(0.5)
+
+    def shutdown(self):
+        pass
+
+
+available = dict()
+
+# todo: loading the monitor drivers should be automatic
+from Bcfg2.Server.FileMonitor.Pseudo import Pseudo
+available['pseudo'] = Pseudo
+
+try:
+    from Bcfg2.Server.FileMonitor.Fam import Fam
+    available['fam'] = Fam
+except ImportError:
+    pass
+
+try:
+    from Bcfg2.Server.FileMonitor.Gamin import Gamin
+    available['gamin'] = Gamin
+except ImportError:
+    pass
+
+try:
+    from Bcfg2.Server.FileMonitor.Inotify import Inotify
+    available['inotify'] = Inotify
+except ImportError:
+    pass    
+
+for fdrv in sorted(available.keys(), key=lambda k: available[k].__priority__):
+    if fdrv in available:
+        available['default'] = available[fdrv]
+        break