Added helper functions for logging fatal error in ForkedJob

cloudcontrol/node/jobs.py

@@ -5,7 +5,9 @@ import resource
 import signal
 import subprocess
 import sys
+import traceback
 from threading import Thread, Event
+from StringIO import StringIO
 
 from cloudcontrol.node.exc import JobError
 from cloudcontrol.node.utils import num_to_sig
@@ -181,6 +183,47 @@ class ForkedJob(object):
         # overide in sub class
         pass
 
+    def fatal(self, fmt, *args, **kwargs):
+        """Write error message in stderr and exit.
+
+        :param str fmt: format string
+        :param \*args: arguments for format string
+        :param \*\*kwargs: can contain ('status', :int:) -> exit status of process
+        """
+        try:
+            status = int(kwargs.get('status', 1))
+        except (ValueError, TypeError):
+            sys.stderr.write('Bad status argument %s' % status)
+            os._exit(42)
+
+        try:
+            fmt = fmt % args
+        except (ValueError, TypeError):
+            sys.stderr.write('Bad formatting for string: %s' % fmt)
+            os._exit(42)
+
+        try:
+            sys.stderr.write(fmt)
+        except IOError:
+            os._exit(42)
+
+        os._exit(status)
+
+    def fatal_exc(self, fmt, *args, **kwargs):
+        """Write error message and traceback and exit.
+
+        :param str fmt: format string
+        :param \*args: arguments for format string
+        :param \*\*kwargs: can contain ('status', :int:) -> exit status of process
+        """
+        tb = StringIO()
+        tb.write('\n')
+        traceback.print_exc(file=tb)
+        tb.write('\n')
+        fmt += '%s'
+        args = args + (tb.getvalue(),)
+        self.fatal(fmt, *args, status=kwargs.get('status', 1))
+
     def close_fds(self):
         """Close all fds uneeded fds in children."""
         # get max fd