Don't handle koji messages with null task_id values.

Otherwise, we query for null==null in our DB and chaos ensues.

module_build_service/messaging.py

@@ -186,6 +186,10 @@ class BaseMessage(object):
                 build_version = msg_inner_msg.get('version')
                 build_release = msg_inner_msg.get('release')
 
+                if task_id is None:
+                    log.debug("Saw a koji build change with no task_id.")
+                    return
+
                 msg_obj = KojiBuildChange(
                     msg_id, build_id, task_id, build_new_state, build_name,
                     build_version, build_release)
@@ -225,6 +229,8 @@ class KojiBuildChange(BaseMessage):
     def __init__(self, msg_id, build_id, task_id, build_new_state, build_name,
                  build_version, build_release, module_build_id=None,
                  state_reason=None):
+        if task_id is None:
+            raise ValueError("KojiBuildChange with a null task_id is invalid.")
         super(KojiBuildChange, self).__init__(msg_id)
         self.build_id = build_id
         self.task_id = task_id

module_build_service/scheduler/handlers/components.py

@@ -50,6 +50,8 @@ def _finalize(config, session, msg, state):
         log.debug("We have no record of %s" % nvr)
         return
 
+    log.info("Saw relevant component build of %r from %r." % (nvr, msg.msg_id))
+
     if msg.state_reason:
         state_reason = msg.state_reason
     elif state != koji.BUILD_STATES['COMPLETE']: