More refactoring

README.md

@@ -24,7 +24,7 @@ entires sent by containers and writes them to disk on the host.
 
 **Running**
 
-* `loginjector_daemon -s unix://var/run/docker.sock -o /var/log/container/`
+* `loginjector -s unix://var/run/docker.sock -o /var/log/container/`
 
 (The above arguments are actually the defaults and need not be specified)
 

loginjector/loginjector.py

@@ -7,13 +7,14 @@ import socket
 import logging
 import argparse
 
-from time import sleep
 from select import select
 from threading import Thread, Lock, Timer
+from requests import exceptions as requests_exc
 from collections import defaultdict, namedtuple
 
 from docker import tls  # NOQA
-from docker import Client, errors
+from docker import Client
+from docker import errors as docker_exc
 
 from jinja2 import Environment
 
@@ -82,8 +83,8 @@ class LogInjectorDaemon(object):
         self.loggers_lock = Lock()
         self.container_names = {}
 
-        self.rescan_delay = 10
+        self.rescan_delay = 30
-        self.rescans = 1
+        self.rescans = 2
 
         signal.signal(signal.SIGTERM, self.signal_handler)
 
@@ -113,7 +114,7 @@ class LogInjectorDaemon(object):
                 change_listner.join(0.1)
                 message_recvr.join(0.1)
         except KeyboardInterrupt:
-            pass
+            self.signal_handler(None, None)
 
         self.docker.close()
 
@@ -167,13 +168,15 @@ class LogInjectorDaemon(object):
             Thread(target=self.relisten_on, args=(event["id"],)).start()
 
         elif event["status"] == "die":
-            Thread(target=self.end_listen_on, args=(event["id"],)).start()
+            # delay ending listener so remaining messages have time to flush
+            t = Timer(10, self.end_listen_on, args=(event["id"],))
+            t.daemon = True
+            t.start()
 
     def end_listen_on(self, container_id):
         """
         Kill local listener for container_id
         """
-        sleep(10)  # hack: kill some time for any straggling log messages to be flushed out
         with self.loggers_lock:
             loggers_to_close = [l for l in self.loggers.keys() if self.loggers[l]["container_id"] == container_id]
 
@@ -208,17 +211,14 @@ class LogInjectorDaemon(object):
                 self.container_names[container_id] = raw_name
                 logging.info("{}: is named {}".format(container_id, raw_name))
 
-        except errors.NotFound:
+        except (docker_exc.NotFound, requests_exc.ReadTimeout):
             logging.info("{}: no longer exists, aborting".format(container_id))
             return
 
         logging.info("{}: setup".format(container_id))
 
         # Check for commonly know processes in the container
-        ps_output = self.exec_in_container(container_id,
+        ps_lines = self.get_running_procs(container_id)
-                                           "ps --ppid 2 -p 2 --deselect -o cmd --no-headers").decode('utf-8')
-        ps_lines = [line.strip() for line in ps_output.split("\n") if line]
-        # logging.info("{}: running procs: {}".format(container_id, str(ps_lines)))
 
         # look at ps, see no syslog
         if any(["rsyslogd" in i for i in ps_lines]):
@@ -240,9 +240,12 @@ class LogInjectorDaemon(object):
                 logging.info("{}: no log files found, ignoring".format(container_id))
                 return None
 
-            logging.info("{}: no log files found, scheduling rescan #{} in {} seconds".format(container_id, rescan_num,
+            logging.info("{}: no log files found, scheduling rescan #{} in {} seconds".format(container_id,
+                                                                                              rescan_num,
                                                                                               self.rescan_delay))
-            Timer(self.rescan_delay, self.relisten_on, args=[container_id, rescan_num - 1]).start()
+            t = Timer(self.rescan_delay, self.relisten_on, args=[container_id, rescan_num - 1])
+            t.daemon = True
+            t.start()
             return None
 
         syslog_conf = self.render_template(container_id, self.template, modules_use)
@@ -254,6 +257,14 @@ class LogInjectorDaemon(object):
         logging.info("{}: spawning rsyslogd".format(container_id))
         self.exec_in_container(container_id, '/usr/sbin/rsyslogd')
 
+    def get_running_procs(self, container_id):
+        """
+        Runs `ps` in a container to get a list of processes
+        """
+        ps_output = self.exec_in_container(container_id,
+                                           "ps --ppid 2 -p 2 --deselect -o cmd --no-headers").decode('utf-8')
+        return [line.strip() for line in ps_output.split("\n") if line]
+
     def render_template(self, container_id, template_contents, log_modules):
         """
         Create a rsyslog config from template

setup.py

@@ -12,8 +12,6 @@ setup(name='loginjector',
       packages=['loginjector'],
       entry_points={
           'console_scripts': [
-              'loginjector_daemon = loginjector.loginjector:shell',
+              'loginjector = loginjector.loginjector:shell',
           ]
-      },
+      })
-      #install_requires=['requests==2.10.0']
-      )