Graph tab will not work when a processor is not found from an exchange.

[tngTUDOR]

What do you want to report?

In the following scenario, AB gets almost unresponsive, and the terminal keeps showing an error and makes AB almost unuseable when selecting the graph tab of a node (activity):

A project+database+activities+exchanges are created outside of AB (i.e.: only with brightway) and the user does not create a "production" edge with a product for a node.

The error is that the activity_browser.layouts.pages.activity_details.graph_tab function: get_processor_from_exchange naively returns processors[0], which in the in previous scenario is empty.

This does not happen when the activity is directly created with AB.

Relevant errors

IndexError: list index out of range
Error calling Python override of QTreeView::mouseDoubleClickEvent(): 09:36:14 | ERROR | IndexError: list index out of range
Traceback (most recent call last):
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/panes/database_products.py", line 346, in mouseDoubleClickEvent
actions.ActivityOpen.run(self.selected_activities)
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/actions/base.py", line 59, in wrapper
raise e
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/actions/base.py", line 49, in wrapper
func(*args, **kwargs)
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/actions/activity/activity_open.py", line 58, in run
page = pages.ActivityDetailsPage(act)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/pages/activity_details/activity_details.py", line 83, in __init__
self.sync()
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/pages/activity_details/activity_details.py", line 168, in sync
self.graph_explorer.sync()
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/pages/activity_details/graph_tab.py", line 74, in sync
json = self.build_json()
^^^^^^^^^^^^^^^^^
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/pages/activity_details/graph_tab.py", line 111, in build_json
processor = get_processor_from_exchange(exc)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/loyaveun/mambaforge/envs/ab-sample/lib/python3.12/site-packages/activity_browser/layouts/pages/activity_details/graph_tab.py", line 189, in get_processor_from_exchange
processor = processors[0]
~~~~~~~~~~^^^
IndexError: list index out of range

Version

3.0.0b1163

Installation method

PyPI (pip)

Operating system

Linux
Windows 11

[bsteubing]

Hi @tngTUDOR, thanks for reporting this. I am not super familiar with this part of the code. However, I am wondering why one would create a process without a function (LCA terminology here, not python one). Any process must have a function, a reason to exist.