Remove double accounting of builds

The "building_jobs" dictionary on pipeline managers is no longer
necessary because the object data model is sufficient to find all
of the running builds.  Remove the unnecessary second list.

Some of the protections that checked that builds were in this
dictionary are also no longer needed as it is not possible to
receive a result for a build that the running Zuul did not
request since the change to use Gearman.

Change-Id: I10de7edcf8356885f5f2d2f45d7014582bcbc3cf

zuul/scheduler.py

@@ -567,6 +567,7 @@ class Scheduler(threading.Thread):
                     continue
                 self.log.debug("Re-enqueueing changes for pipeline %s" % name)
                 items_to_remove = []
+                builds_to_remove = []
                 for shared_queue in old_pipeline.queues:
                     for item in shared_queue.queue:
                         item.item_ahead = None
@@ -582,32 +583,25 @@ class Scheduler(threading.Thread):
                             continue
                         item.change.project = project
                         for build in item.current_build_set.getBuilds():
-                            build.job = layout.jobs.get(build.job.name,
-                                                        build.job)
+                            job = layout.jobs.get(build.job.name)
+                            if job:
+                                build.job = job
+                            else:
+                                builds_to_remove.append(build)
                         if not new_pipeline.manager.reEnqueueItem(item):
                             items_to_remove.append(item)
-                builds_to_remove = []
-                for build, item in old_pipeline.manager.building_jobs.items():
-                    if item in items_to_remove:
+                for item in items_to_remove:
+                    for build in item.current_build_set.getBuilds():
                         builds_to_remove.append(build)
-                        self.log.warning(
-                            "Deleting running build %s for change %s whose "
-                            "item was not re-enqueued" % (build, item.change))
-                    if build.job not in new_pipeline.getJobs(item.change):
-                        builds_to_remove.append(build)
-                        self.log.warning(
-                            "Deleting running build %s for change %s because "
-                            "the job is not defined" % (build, item.change))
                 for build in builds_to_remove:
+                    self.log.warning(
+                        "Canceling build %s during reconfiguration" % (build,))
                     try:
                         self.launcher.cancel(build)
                     except Exception:
                         self.log.exception(
                             "Exception while canceling build %s "
                             "for change %s" % (build, item.change))
-                    del old_pipeline.manager.building_jobs[build]
-                new_pipeline.manager.building_jobs = \
-                    old_pipeline.manager.building_jobs
             self.layout = layout
             for trigger in self.triggers.values():
                 trigger.postConfig()
@@ -668,9 +662,12 @@ class Scheduler(threading.Thread):
         if self.merger.areMergesOutstanding():
             waiting = True
         for pipeline in self.layout.pipelines.values():
-            for build in pipeline.manager.building_jobs.keys():
-                self.log.debug("%s waiting on %s" % (pipeline.manager, build))
-                waiting = True
+            for item in pipeline.getAllItems():
+                for build in item.current_build_set.getBuilds():
+                    if build.result is None:
+                        self.log.debug("%s waiting on %s" %
+                                       (pipeline.manager, build))
+                        waiting = True
         if not waiting:
             self.log.debug("All builds are complete")
             return True
@@ -888,7 +885,6 @@ class BasePipelineManager(object):
     def __init__(self, sched, pipeline):
         self.sched = sched
         self.pipeline = pipeline
-        self.building_jobs = {}
         self.event_filters = []
         if self.sched.config and self.sched.config.has_option(
             'zuul', 'report_times'):
@@ -1157,7 +1153,6 @@ class BasePipelineManager(object):
                 build = self.sched.launcher.launch(job, item,
                                                    self.pipeline,
                                                    dependent_items)
-                self.building_jobs[build] = item
                 self.log.debug("Adding build %s of job %s to item %s" %
                                (build, job, item))
                 item.addBuild(build)
@@ -1173,24 +1168,17 @@ class BasePipelineManager(object):
     def cancelJobs(self, item, prime=True):
         self.log.debug("Cancel jobs for change %s" % item.change)
         canceled = False
-        to_remove = []
+        old_build_set = item.current_build_set
         if prime and item.current_build_set.ref:
             item.resetAllBuilds()
-        for build, build_item in self.building_jobs.items():
-            if build_item == item:
-                self.log.debug("Found build %s for change %s to cancel" %
-                               (build, item.change))
-                try:
-                    self.sched.launcher.cancel(build)
-                except:
-                    self.log.exception("Exception while canceling build %s "
-                                       "for change %s" % (build, item.change))
-                to_remove.append(build)
-                canceled = True
-        for build in to_remove:
-            self.log.debug("Removing build %s from running builds" % build)
+        for build in old_build_set.getBuilds():
+            try:
+                self.sched.launcher.cancel(build)
+            except:
+                self.log.exception("Exception while canceling build %s "
+                                   "for change %s" % (build, item.change))
             build.result = 'CANCELED'
-            del self.building_jobs[build]
+            canceled = True
         for item_behind in item.items_behind:
             self.log.debug("Canceling jobs for change %s, behind change %s" %
                            (item_behind.change, item.change))
@@ -1306,31 +1294,17 @@ class BasePipelineManager(object):
                 self.sched.launcher.setBuildDescription(build, desc)
 
     def onBuildStarted(self, build):
-        if build not in self.building_jobs:
-            # Or triggered externally, or triggered before zuul started,
-            # or restarted
-            return False
-
         self.log.debug("Build %s started" % build)
         self.updateBuildDescriptions(build.build_set)
         return True
 
     def onBuildCompleted(self, build):
-        if build not in self.building_jobs:
-            # Or triggered externally, or triggered before zuul started,
-            # or restarted
-            return False
-
         self.log.debug("Build %s completed" % build)
-        change = self.building_jobs[build]
-        self.log.debug("Found change %s which triggered completed build %s" %
-                       (change, build))
-
-        del self.building_jobs[build]
+        item = build.build_set.item
 
-        self.pipeline.setResult(change, build)
-        self.log.debug("Change %s status is now:\n %s" %
-                       (change, self.pipeline.formatStatus(change)))
+        self.pipeline.setResult(item, build)
+        self.log.debug("Item %s status is now:\n %s" %
+                       (item, self.pipeline.formatStatus(item)))
         self.updateBuildDescriptions(build.build_set)
         return True