From d15abaa25fc374830163147345ec3688102b2bb1 Mon Sep 17 00:00:00 2001
From: Clark Boylan <clark.boylan@gmail.com>
Date: Tue, 31 Jul 2012 09:35:19 -0700
Subject: [PATCH] Use gerritlib for event-stream consumption.

Gerritlib is now available for Gerrit event stream consumption. Use
it. This should fix the bug where events are missed due to the
connection dying and the resulting wait for five seconds.

Change-Id: I63e7c3064a42379c985f1a0a723d08c15a1be003
---
 gerritbot/bot.py   | 98 ++++++++++++++--------------------------------
 tools/pip-requires |  3 +-
 2 files changed, 32 insertions(+), 69 deletions(-)

diff --git a/gerritbot/bot.py b/gerritbot/bot.py
index eff76a5..53eff5e 100755
--- a/gerritbot/bot.py
+++ b/gerritbot/bot.py
@@ -29,17 +29,14 @@ openstack-dev:
       - master
 """
 
-import irc.bot
-import time
-import subprocess
-import threading
-import select
-import json
-import sys
-import os
 import ConfigParser
 import daemon
-import traceback
+import irc.bot
+import logging.config
+import os
+import sys
+import threading
+import time
 import yaml
 
 try:
@@ -80,40 +77,14 @@ class GerritBot(irc.bot.SingleServerIRCBot):
 
 
 class Gerrit(threading.Thread):
-    def __init__(self, ircbot, channel_config,
-                 username, keyfile, server, port=29418):
+    def __init__(self, ircbot, channel_config, server,
+                 username, port=29418, keyfile=None):
         threading.Thread.__init__(self)
         self.ircbot = ircbot
         self.channel_config = channel_config
-        self.username = username
-        self.keyfile = keyfile
-        self.server = server
-        self.port = port
-        self.proc = None
-        self.poll = select.poll()
-
-    def _open(self):
-        self.proc = subprocess.Popen(['/usr/bin/ssh', '-p', str(self.port),
-                                      '-i', self.keyfile,
-                                      '-l', self.username, self.server,
-                                      'gerrit', 'stream-events'],
-                                     bufsize=1,
-                                     stdin=None,
-                                     stdout=subprocess.PIPE,
-                                     stderr=None,
-                                     )
-        self.poll.register(self.proc.stdout)
-
-    def _close(self):
-        try:
-            self.poll.unregister(self.proc.stdout)
-        except:
-            pass
-        try:
-            self.proc.kill()
-        except:
-            pass
-        self.proc = None
+        # Import here because it needs to happen after daemonization
+        import gerritlib.gerrit
+        self.gerrit = gerritlib.gerrit.Gerrit(server, username, port, keyfile)
 
     def patchset_created(self, channel, data):
         msg = '%s proposed a change to %s: %s  %s' % (
@@ -174,9 +145,7 @@ class Gerrit(threading.Thread):
             data['change']['url'])
         self.ircbot.send(channel, msg)
 
-    def _read(self):
-        l = self.proc.stdout.readline()
-        data = json.loads(l)
+    def _read(self, data):
         channel_set = (self.channel_config.projects.get(
                             data['change']['project'], set()) &
                        self.channel_config.events.get(
@@ -191,30 +160,11 @@ class Gerrit(threading.Thread):
             elif data['type'] == 'change-merged':
                 self.change_merged(channel, data)
 
-    def _listen(self):
-        while True:
-            ret = self.poll.poll()
-            for (fd, event) in ret:
-                if fd == self.proc.stdout.fileno():
-                    if event == select.POLLIN:
-                        self._read()
-                    else:
-                        raise Exception("event on ssh connection")
-
-    def _run(self):
-        try:
-            if not self.proc:
-                self._open()
-            self._listen()
-        except:
-            traceback.print_exc()
-            self._close()
-            time.sleep(5)
-
     def run(self):
-        time.sleep(5)
+        self.gerrit.startWatching()
         while True:
-            self._run()
+            event = self.gerrit.getEvent()
+            self._read(event)
 
 
 class ChannelConfig(object):
@@ -246,6 +196,7 @@ class ChannelConfig(object):
 def _main():
     config = ConfigParser.ConfigParser()
     config.read(sys.argv[1])
+    setup_logging(config)
 
     fp = config.get('ircbot', 'channel_config')
     if fp:
@@ -264,10 +215,10 @@ def _main():
                     config.getint('ircbot', 'port'))
     g = Gerrit(bot,
                channel_config,
-               config.get('gerrit', 'user'),
-               config.get('gerrit', 'key'),
                config.get('gerrit', 'host'),
-               config.getint('gerrit', 'port'))
+               config.get('gerrit', 'user'),
+               config.getint('gerrit', 'port'),
+               config.get('gerrit', 'key'))
     g.start()
     bot.start()
 
@@ -283,5 +234,16 @@ def main():
         _main()
 
 
+def setup_logging(config):
+    if config.has_option('gerrit', 'log_config'):
+        log_config = config.get('gerrit', 'log_config')
+        fp = os.path.expanduser(log_config)
+        if not os.path.exists(fp):
+            raise Exception("Unable to read logging config file at %s" % fp)
+        logging.config.fileConfig(fp)
+    else:
+        logging.basicConfig(level=logging.DEBUG)
+
+
 if __name__ == "__main__":
     main()
diff --git a/tools/pip-requires b/tools/pip-requires
index ddf5b57..efecad9 100644
--- a/tools/pip-requires
+++ b/tools/pip-requires
@@ -1,3 +1,4 @@
+gerritlib
+irc
 pyyaml
 python-daemon
-irc