Move recovery functionality for getting perticular workflow versions into StoredWorkflow

lib/galaxy/managers/workflows.py

@@ -377,6 +377,8 @@ class WorkflowContentsManager(UsesAnnotations):
         option describes the workflow in a context more tied to the current Galaxy instance and includes
         fields like 'url' and 'url' and actual unencoded step ids instead of 'order_index'.
         """
+        if version == '':
+            version = None
         if version is not None:
             version = int(version)
         if style == "editor":
@@ -394,7 +396,7 @@ class WorkflowContentsManager(UsesAnnotations):
         """
         Builds workflow dictionary used by run workflow form
         """
-        workflow = stored.latest_workflow if version is None else stored.workflows[version]
+        workflow = stored.get_internal_version(version)
         if len(workflow.steps) == 0:
             raise exceptions.MessageException('Workflow cannot be run because it does not have any steps.')
         if attach_ordered_steps(workflow, workflow.steps):
@@ -478,11 +480,7 @@ class WorkflowContentsManager(UsesAnnotations):
         return self._resource_mapper_function(trans=trans, stored_workflow=stored, workflow=workflow)
 
     def _workflow_to_dict_editor(self, trans, stored, version=None):
-        if version is None:
-            workflow = stored.latest_workflow
-        else:
-            version = int(version)
-            workflow = stored.workflows[version]
+        workflow = stored.get_internal_version(version)
         # Pack workflow data into a dictionary and return
         data = {}
         data['name'] = workflow.name
@@ -594,10 +592,7 @@ class WorkflowContentsManager(UsesAnnotations):
         """
         if workflow is None:
             assert stored is not None
-            if version is None:
-                workflow = stored.latest_workflow
-            else:
-                workflow = stored.workflows[version]
+            workflow = stored.get_internal_version(version)
 
         annotation_str = ""
         tag_str = ""
@@ -767,7 +762,7 @@ class WorkflowContentsManager(UsesAnnotations):
         encode = self.app.security.encode_id
         sa_session = self.app.model.context
         item = stored.to_dict(view='element', value_mapper={'id': encode})
-        workflow = stored.latest_workflow if version == None else stored.workflows[version]
+        workflow = stored.get_internal_version(version)
         item['url'] = url_for('workflow', id=item['id'])
         item['owner'] = stored.user.username
         inputs = {}

lib/galaxy/model/__init__.py

@@ -3906,6 +3906,13 @@ class StoredWorkflow(HasTags, Dictifiable):
         self.latest_workflow_id = None
         self.workflows = []
 
+    def get_internal_version(self, version):
+        if version is None:
+            return self.latest_workflow
+        if len(self.workflows) <= version:
+            raise Exception("Version does not exist")
+        return list(reversed(self.workflows))[version]
+
     def copy_tags_from(self, target_user, source_workflow):
         # Override to only copy owner tags.
         for src_swta in source_workflow.owner_tags: