From ec71a8463ca092367847d6bfc40c20805b3cdb29 Mon Sep 17 00:00:00 2001
From: Lance Edgar <lance@edbob.org>
Date: Fri, 10 Aug 2012 22:44:43 -0700
Subject: [PATCH] add errors module (sys.excepthook), made win32 filemon use it

---
 edbob/errors.py               | 72 +++++++++++++++++++++++++++++++++++
 edbob/filemon/win32_server.py | 37 ++++++++++++++++--
 2 files changed, 105 insertions(+), 4 deletions(-)
 create mode 100644 edbob/errors.py

diff --git a/edbob/errors.py b/edbob/errors.py
new file mode 100644
index 0000000..66a1ab6
--- /dev/null
+++ b/edbob/errors.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python
+# -*- coding: utf-8  -*-
+################################################################################
+#
+#  edbob -- Pythonic Software Framework
+#  Copyright © 2010-2012 Lance Edgar
+#
+#  This file is part of edbob.
+#
+#  edbob is free software: you can redistribute it and/or modify it under the
+#  terms of the GNU Affero General Public License as published by the Free
+#  Software Foundation, either version 3 of the License, or (at your option)
+#  any later version.
+#
+#  edbob is distributed in the hope that it will be useful, but WITHOUT ANY
+#  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+#  FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for
+#  more details.
+#
+#  You should have received a copy of the GNU Affero General Public License
+#  along with edbob.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+
+"""
+``edbob.errors`` -- Error Alert Emails
+"""
+
+import sys
+import socket
+import logging
+from traceback import format_exception
+from cStringIO import StringIO
+
+import edbob
+from edbob.mail import sendmail_with_config
+
+
+log = logging.getLogger(__name__)
+
+
+def init(config):
+    """
+    Creates a system-wide exception hook which logs exceptions and emails them
+    to configured recipient(s).
+    """
+
+    def excepthook(type, value, traceback):
+        log.exception("An exception occurred")
+        email_exception(type, value, traceback)
+        sys.__excepthook__(type, value, traceback)
+
+    sys.excepthook = excepthook
+
+
+def email_exception(type, value, traceback):
+    """
+    Sends an email containing a traceback to the configured recipient(s).
+    """
+
+    body = StringIO()
+
+    hostname = socket.gethostname()
+    body.write("An exception occurred.\n")
+    body.write("\n")
+    body.write("Machine Name:  %s (%s)\n" % (hostname, socket.gethostbyname(hostname)))
+    body.write("Local Time:    %s\n" % (edbob.local_time().strftime('%Y-%m-%d %H:%M:%S %Z%z')))
+    body.write("\n")
+    body.write("%s\n" % ''.join(format_exception(type, value, traceback)))
+
+    sendmail_with_config('errors', body.getvalue())
+    body.close()
diff --git a/edbob/filemon/win32_server.py b/edbob/filemon/win32_server.py
index 8e5c150..03e5c0a 100644
--- a/edbob/filemon/win32_server.py
+++ b/edbob/filemon/win32_server.py
@@ -27,16 +27,17 @@
 """
 
 import os.path
+import sys
 import socket
 import time
 import Queue
+from traceback import format_exception
 
 import edbob
 from edbob.filemon import MonitorProfile
 from edbob.filemon.win32 import WatcherWin32, ACTION_CREATE, ACTION_UPDATE
 from edbob.win32 import file_is_free
 
-import sys
 if sys.platform == 'win32': # docs should build for everyone
     import win32serviceutil
     import win32service
@@ -94,8 +95,9 @@ class FileMonitorService(win32serviceutil.ServiceFramework):
             except Queue.Empty:
                 pass
             else:
-                if ftype == 'file' and action in (
-                    ACTION_CREATE, ACTION_UPDATE):
+                # if ftype == 'file' and action in (
+                #     ACTION_CREATE, ACTION_UPDATE):
+                if ftype == 'file' and action == ACTION_CREATE:
                     self.do_actions(key, fpath)
             win32api.SleepEx(250, True)
 
@@ -118,7 +120,34 @@ class FileMonitorService(win32serviceutil.ServiceFramework):
                 func = action
                 args = []
             func = edbob.load_spec(func)
-            func(path, *args)
+
+            try:
+                func(path, *args)
+            except:
+
+                exc_info = sys.exc_info()
+
+                # Call the system exception hook in case anything special has
+                # been registered there, e.g. if edbob.errors.init() has
+                # happened.  Note that this is especially necessary since
+                # PythonService.exe doesn't seem to honor sys.excepthook.
+                sys.excepthook(*exc_info)
+
+                # Go ahead and write exception info to the Windows Event Log
+                # while we're at it.
+                msg = "File monitor action failed.\n"
+                msg += "\n"
+                msg += "Profile:  %s\n" % key
+                msg += "Action:  %s\n" % action
+                msg += "File Path:  %s\n" % path
+                msg += "\n"
+                msg += ''.join(format_exception(*exc_info))
+                servicemanager.LogErrorMsg(msg)
+
+                # Don't re-raise the exception since the service should
+                # continue running despite any problems it encounters.  But
+                # this file probably shouldn't be processed any further.
+                break
 
     
 if __name__ == '__main__':