Add source interface for setting change attributes

Changes are mostly created and updated by the drivers. However, since
there are some change attributes that are also modified from other parts
of the code, we need to make sure to update the cache in Zookeeper in
those cases. For this we introduce `setChangeAttributes()` as an
additional `Source` interface.

Change-Id: Iab9bc4a6e40f254c1cbc4405e90cb5f03e3ecd56

zuul/manager/__init__.py

@@ -599,7 +599,6 @@ class PipelineManager(metaclass=ABCMeta):
 
         # Search for Depends-On headers and find appropriate changes
         log.debug("  Updating commit dependencies for %s", change)
-        change.refresh_deps = False
         dependencies = []
         seen = set()
         for match in find_dependency_headers(change.message):
@@ -620,7 +619,12 @@ class PipelineManager(metaclass=ABCMeta):
             if dep and (not dep.is_merged) and dep not in dependencies:
                 log.debug("  Adding dependency: %s", dep)
                 dependencies.append(dep)
-        change.commit_needs_changes = dependencies
+        source = self.sched.connections.getSource(
+            change.project.connection_name)
+        source.setChangeAttributes(
+            change,
+            commit_needs_changes=[d for d in dependencies],
+            refresh_deps=False)
 
     def provisionNodes(self, item):
         log = item.annotateLogger(self.log)
@@ -1458,7 +1462,9 @@ class PipelineManager(metaclass=ABCMeta):
 
     def onFilesChangesCompleted(self, event, build_set):
         item = build_set.item
-        item.change.files = event.files
+        source = self.sched.connections.getSource(
+            item.change.project.connection_name)
+        source.setChangeAttributes(item.change, files=event.files)
         build_set.files_state = build_set.COMPLETE
 
     def onMergeCompleted(self, event, build_set):
@@ -1469,7 +1475,11 @@ class PipelineManager(metaclass=ABCMeta):
 
     def _onMergeCompleted(self, event, build_set):
         item = build_set.item
-        item.change.containing_branches = event.item_in_branches
+        source = self.sched.connections.getSource(
+            item.change.project.connection_name)
+        if isinstance(item.change, model.Tag):
+            source.setChangeAttributes(
+                item.change, containing_branches=event.item_in_branches)
         build_set.merge_state = build_set.COMPLETE
         build_set.repo_state = event.repo_state
         if event.merged:

zuul/scheduler.py

@@ -2192,8 +2192,11 @@ class Scheduler(threading.Thread):
                     continue
                 for dep in other_change.commit_needs_changes:
                     if change.isUpdateOf(dep):
-                        other_change.refresh_deps = True
-        change.refresh_deps = True
+                        source.setChangeAttributes(
+                            other_change, refresh_deps=True)
+
+        source = self.connections.getSource(change.project.connection_name)
+        source.setChangeAttributes(change, refresh_deps=True)
 
     def cancelJob(self, buildset, job, build=None, final=False,
                   force=False):

zuul/source/__init__.py

@@ -126,3 +126,15 @@ class BaseSource(object, metaclass=abc.ABCMeta):
     def getRejectFilters(self, config):
         """Return a list of ChangeFilters for the scheduler to match against.
         """
+
+    def setChangeAttributes(self, change, **attrs):
+        """"Set the provided attributes on the given change.
+
+        This method must be used when modifying attributes of a change
+        outside the driver context. The driver needs to make sure that
+        the change is also reflected in the cache in Zookeeper.
+        """
+        # TODO (swestphahl): Remove this workaround after all drivers
+        # have been converted to use a Zookeeper backed changed cache.
+        for name, value in attrs.items():
+            setattr(change, name, value)