remove every-30-second SchedulerManager trigger, in favor of one

post-reconfig trigger

This revealed a bug in Periodic (not scheduling a wakeup for the next
periodic build), now fixed. Unit tests were updated too.

I left a "just_poll" flag in place for a future config knob to enable the
multiple-masters-sharing-one-DB mode.

buildbot/master.py

@@ -18,11 +18,9 @@
 from buildbot.util import now, safeTranslate
 from buildbot.pbutil import NewCredPerspective
 from buildbot.process.builder import Builder, IDLE
-from buildbot.buildrequest import BuildRequest
 from buildbot.status.builder import Status, BuildSetStatus
 from buildbot.changes.changes import Change
 from buildbot.changes.manager import ChangeManager
-from buildbot.sourcestamp import SourceStamp
 from buildbot.buildslave import BuildSlave
 from buildbot import interfaces, locks
 from buildbot.process.properties import Properties
@@ -442,10 +440,20 @@ def __init__(self, basedir, configFileName="master.cfg", db=None):
         self.db.subscribe_to("modify-buildset", sm.trigger_modify_buildset)
         self.scheduler_manager = sm
         sm.setServiceParent(self)
-        # it'd be nice if TimerService let us set now=False
-        t = internet.TimerService(30, sm.trigger)
-        t.setServiceParent(self)
-        # should we try to remove this? Periodic() requires at least one kick
+        # TODO: this will turn into a config knob somehow. Set it if you are
+        # using multiple buildmasters that share a common database, such that
+        # the masters need to discover what each other is doing by polling
+        # the database. TODO: this will turn into the DBNotificationServer.
+        just_poll = False
+        if just_poll:
+            # it'd be nice if TimerService let us set now=False
+            t1 = internet.TimerService(30, sm.trigger)
+            t1.setServiceParent(self)
+            t2 = internet.TimerService(30, self.botmaster.loop.trigger)
+            t2.setServiceParent(self)
+        # adding schedulers (like when loadConfig happens) will trigger the
+        # scheduler loop at least once, which we need to jump-start things
+        # like Periodic.
 
         self.status = Status(self.botmaster, self.db, self.basedir)
         self.statusTargets = []

buildbot/schedulers/manager.py

@@ -39,6 +39,7 @@
 from twisted.python import log
 from buildbot import loop
 from buildbot.util import defaultdict
+from buildbot.eventual import eventually
 
 class SchedulerManager(loop.MultiServiceLoop):
     def __init__(self, master, db, change_svc):
@@ -94,6 +95,7 @@ def _attach(ign):
             for s in list(self):
                 if s.upstream_name:
                     self.upstream_subscribers[s.upstream_name].append(s)
+            eventually(self.trigger)
         d.addCallback(_attach)
         d.addErrback(log.err)
         return d

buildbot/schedulers/timed.py

@@ -99,13 +99,14 @@ def _run(self, t):
         if last_build is None:
             self.start_HEAD_build(t)
             self.update_last_build(t, now)
-            return None
+            last_build = now
         when = last_build + self.periodicBuildTimer
         if when < now:
             self.start_HEAD_build(t)
             self.update_last_build(t, now)
-            return None
-        return when - now + 1.0
+            last_build = now
+            when = now + self.periodicBuildTimer
+        return when + 1.0
 
 
 class Nightly(_Base, ClassifierMixin, TimedBuildMixin):

buildbot/test/runs/test_db.py

@@ -48,6 +48,7 @@
 from buildbot.changes.manager import ChangeManager
 from buildbot.test.pollmixin import PollMixin
 from buildbot.test.runutils import RunMixin
+from buildbot.eventual import flushEventualQueue
 
 class ShouldFailMixin:
 
@@ -285,6 +286,7 @@ def _check4(ign):
             self.failUnlessEqual(all[0].name, "one")
             self.failUnlessEqual(all[1].builderNames, ["builder-two-other"])
         d.addCallback(_check4)
+        d.addCallback(flushEventualQueue)
         return d
 
     def stall(self, res, timeout):

buildbot/test/unit/test_scheduler.py

@@ -18,20 +18,26 @@ def setSchedulers(self, *schedulers):
     def testPeriodic1(self):
         self.basedir = 'scheduler/Scheduling/testPeriodic1'
         self.create_master()
+        # updateSchedulers itself fires the first trigger
         d = self.setSchedulers(scheduler.Periodic("quickly", ["a","b"], 2))
-        d.addCallback(lambda ign: self.master.scheduler_manager.trigger())
-        d.addCallback(self.stall, 2)
-        d.addCallback(lambda ign: self.master.scheduler_manager.when_quiet())
+        # there should be one buildset submitted at startup, and another a
+        # few seconds later. We wait until we've seen at least two.
+        def _pollf():
+            bsids = self.master.db.get_active_buildset_ids()
+            return bool(len(bsids) > 1)
+        d.addCallback(lambda ign: self.poll(_pollf, 0.1))
         d.addCallback(self._testPeriodic1_1)
         return d
     def _testPeriodic1_1(self, res):
         bsids = self.master.db.get_active_buildset_ids()
         self.failUnless(len(bsids) > 1)
 
-        (external_idstring, reason, ssid, complete, results) = self.master.db.get_buildset_info(bsids[0])
+        (external_idstring, reason, ssid,
+         complete, results) = self.master.db.get_buildset_info(bsids[0])
         reqs = self.master.db.get_buildrequestids_for_buildset(bsids[0])
         self.failUnlessEqual(sorted(reqs.keys()), ["a","b"])
         self.failUnlessEqual(reason, "The Periodic scheduler named 'quickly' triggered this build")
+    testPeriodic1.timeout = 20
 
     def testNightly(self):
         # now == 15-Nov-2005, 00:05:36 AM . By using mktime, this is