Make message ID more easily greppable.

calico/felix/actor.py

@@ -103,6 +103,7 @@
 import gevent.local
 import logging
 import os
+import random
 import sys
 import traceback
 import weakref
@@ -395,7 +396,8 @@ def wait_and_check(async_results):
         r.get()
 
 
-next_message_id = 0
+# Start with a random offset to make the log easier to grep.
+next_message_id = random.randint(0, sys.maxint)
 
 
 class Message(object):
@@ -494,8 +496,11 @@ def queue_fn(self, *args, **kwargs):
             # Allocate a message ID.  We rely on there being no yield point
             # here for thread safety.
             global next_message_id
-            msg_id = next_message_id
-            next_message_id += 1
+            msg_id = "M%016x" % next_message_id
+            if next_message_id == sys.maxint:
+                next_message_id = 0
+            else:
+                next_message_id += 1
 
             if not on_same_greenlet and not async:
                 _stats.increment("Blocking calls started")

calico/felix/test/test_actor.py

@@ -22,7 +22,7 @@
 import logging
 import itertools
 import gc
-from contextlib import nested
+import sys
 
 from gevent.event import AsyncResult
 import mock
@@ -211,6 +211,23 @@ def test_yield(self, m_sleep):
     def test_wait_and_check_no_input(self):
         actor.wait_and_check([])
 
+    def test_wrap_msg_id(self):
+        with mock.patch("calico.felix.actor.next_message_id"):
+            with mock.patch("calico.felix.actor.Message", autospec=True) as m_msg:
+                actor.next_message_id = sys.maxint
+                self._actor.do_a(async=True)
+                self._actor.do_a(async=True)
+
+        self.assertEqual(
+            [c for c in m_msg.mock_calls if c[0] == ""],
+            [
+                mock.call("M" + hex(sys.maxint)[2:], mock.ANY, mock.ANY,
+                          mock.ANY, mock.ANY, needs_own_batch=mock.ANY),
+                mock.call("M0000000000000000", mock.ANY, mock.ANY,
+                          mock.ANY, mock.ANY, needs_own_batch=mock.ANY),
+            ]
+        )
+
 
 class TestExceptionTracking(BaseTestCase):