Add hook for logging.

This may help to debug problems in QA tests.

Reviewed-by: schreiberal

qa/hooks/Makefile.am

-EXTRA_DIST = datehook.py
+EXTRA_DIST = datehook.py loghook.py
 CLEANFILES = *.py[co]

qa/hooks/loghook.py

+# Copyright (C) 2007 Google Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program 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
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+# 02110-1301, USA.
+
+
+"""QA hook to log all function calls.
+
+"""
+
+from ganeti import utils
+
+import qa_utils
+import qa_config
+
+from qa_utils import AssertEqual, StartSSH
+
+
+class LogHook:
+  def __init__(self):
+    file_name = qa_config.get('options', {}).get('hook-logfile', None)
+    if file_name:
+      self.log = open(file_name, "a+")
+    else:
+      self.log = None
+
+  def __del__(self):
+    if self.log:
+      self.log.close()
+
+  def run(self, ctx):
+    if not self.log:
+      return
+
+    msg = "%s-%s" % (ctx.phase, ctx.name)
+    if ctx.phase == 'post':
+      msg += " success=%s" % ctx.success
+    if ctx.args:
+      msg += " %s" % repr(ctx.args)
+    if ctx.kwargs:
+      msg += " %s" % repr(ctx.kwargs)
+    if ctx.phase == 'pre':
+      self.log.write("---\n")
+    self.log.write(msg)
+    self.log.write("\n")
+    self.log.flush()
+
+
+hook = LogHook

qa/qa-sample.yaml

@@ -76,3 +76,6 @@ options:
 
   # Directory containing QA hooks
   #hooks-dir: hooks/
+
+  # Logfile for loghook.py
+  hook-logfile: /tmp/qa.log