Merge branch 'master' into get_ips_per_net

docs/Templates.rst

@@ -20,6 +20,8 @@ Available templates
 +------------------+--------------+
 | el7.3-base       | CentOS 7.3   |
 +------------------+--------------+
+| el7.4-base       | CentOS 7.4   |
++------------------+--------------+
 | fc23-base        | Fedora 23    |
 +------------------+--------------+
 | fc24-base        | Fedora 24    |

lago/cmd.py

@@ -27,6 +27,7 @@
 import sys
 from textwrap import dedent
 import warnings
+from signal import signal, SIGTERM, SIGHUP
 
 import lago
 import lago.plugins
@@ -899,7 +900,30 @@ def create_parser(cli_plugins, out_plugins):
     return parser
 
 
+def exit_handler(signum, frame):
+    """
+    Catch SIGTERM and SIGHUP and call "sys.exit" which raises
+    "SystemExit" exception.
+    This will trigger all the cleanup code defined in ContextManagers
+    and "finally" statements.
+
+    For more details about the arguments see "signal" documentation.
+
+    Args:
+        signum(int): The signal's number
+        frame(frame): The current stack frame, can be None
+    """
+
+    LOGGER.debug('signal {} was caught'.format(signum))
+    sys.exit(128 + signum)
+
+
 def main():
+
+    # Trigger cleanup on SIGTERM and SIGHUP
+    signal(SIGTERM, exit_handler)
+    signal(SIGHUP, exit_handler)
+
     cli_plugins = lago.plugins.load_plugins(
         lago.plugins.PLUGIN_ENTRY_POINTS['cli']
     )

lago/utils.py

@@ -390,6 +390,7 @@ def __enter__(self):
             with ExceptionTimer(timeout=self.timeout):
                 LOGGER.debug('Acquiring lock for {}'.format(self.path))
                 self.lock.acquire()
+                LOGGER.debug('Holding the lock for {}'.format(self.path))
         except TimerException:
             raise TimerException(
                 'Unable to acquire lock for %s in %s secs',
@@ -398,7 +399,10 @@ def __enter__(self):
             )
 
     def __exit__(self, *_):
-        self.lock.release()
+        if self.lock.is_locked():
+            LOGGER.debug('Trying to release lock {}'.format(self.path))
+            self.lock.release()
+            LOGGER.debug('Lock {} was released')
 
 
 def read_nonblocking(file_descriptor):