Use TagHandlerSession in ModelPersistenceContext

Eliminates an unnecessary flush

lib/galaxy/job_execution/output_collect.py

@@ -207,6 +207,13 @@ class JobContext(ModelPersistenceContext, BaseJobContext):
         self.object_store = object_store
         self.final_job_state = final_job_state
         self.flush_per_n_datasets = flush_per_n_datasets
+        self._tag_handler = None
+
+    @property
+    def tag_handler(self):
+        if self._tag_handler is None:
+            self._tag_handler = self.app.tag_handler.create_tag_handler_session()
+        return self._tag_handler
 
     @property
     def work_context(self):
@@ -221,10 +228,6 @@ class JobContext(ModelPersistenceContext, BaseJobContext):
             user = None
         return user
 
-    @property
-    def tag_handler(self):
-        return self.app.tag_handler
-
     def persist_object(self, obj):
         self.sa_session.add(obj)
 

lib/galaxy/model/store/discover.py

@@ -129,13 +129,7 @@ class ModelPersistenceContext(metaclass=abc.ABCMeta):
         if created_from_basename is not None:
             primary_data.created_from_basename = created_from_basename
 
-        has_flushed = False
         if tag_list:
-            # If we have a tag we need a primary id, so need to flush here
-            # TODO: eliminate creating tag associations within create dataset
-            # We can do this incrementally by not passing in a tag list.
-            self.flush()
-            has_flushed = True
             self.tag_handler.add_tags_from_list(self.job.user, primary_data, tag_list)
 
         # Move data from temp location to dataset location

test/unit/jobs/test_job_context.py

@@ -55,6 +55,7 @@ def test_job_context_discover_outputs_flushes_once(mocker):
     job = model.Job()
     job.history = h
     sa_session.add(job)
+    sa_session.flush()
     job_working_directory = tempfile.mkdtemp()
     setup_data(job_working_directory)
     permission_provider = PermissionProvider()