Error switching to different workflow from classification in progress

[mcbouslog]

Package

• app-project / lib-classifier

Describe the bug

Application error.
Appears to be per TasksConnector line 27.
Changing to const latest = subject?.stepHistory?.latest (adding optional chaining to stepHistory) appears to fix the issue.
Not sure how/why subject is defined but stepHistory isn't, thereby creating the issue.

To Reproduce

Steps to reproduce the behavior:

1. Go to https://www.zooniverse.org/projects/humphrydavy/davy-notebooks-project?demo=true
2. Click on a workflow
3. Draw a line and add a test transcription (make sure demo mode enabled)
4. Click the project name to return to the project home page
5. Click on a different workflow

Expected behavior

Loads different workflow.

Additional context

I'm only seeing the bug on Davy Notebooks, not seeing the bug on HMS NHS or Corresponding with Quakers

[mcbouslog]

Possible fix in progress - https://github.com/zooniverse/front-end-monorepo/compare/fix-2809?expand=1, will open PR asap

[eatyourgreens]

@mcbouslog Snapshots can't contain models. They have to be pure snapshots.

[eatyourgreens]

Hard to debug on the live site, but I'm seeing an error in a snapshot processor somewhere.

https://www.zooniverse.org/projects/humphrydavy/davy-notebooks-project/classify/workflow/20178?demo=true

[eatyourgreens]

It's hard to tell in the minified source, but this might be the line that's crashing, when the stored snapshot contains drawing marks (or is this specific to transcription tasks?)

front-end-monorepo/packages/lib-classifier/src/plugins/drawingTools/models/marks/Mark/Mark.js

Line 36 in 4027e64

newSnapshot = Object.assign({}, newSnapshot, { annotations })

EDIT: editing to add that drawing and transcription task annotations are stored as something like task.tool.marks, which is part of the store.workflowSteps model and is persisted in session storage. Other task annotations are stored in store.classifications (I think), which is not persisted.

[eatyourgreens]

I can reproduce the bug live on Davy Notebooks, but not with the transcription task on my staging/testing project. 🤔
https://frontend.preview.zooniverse.org/projects/eatyourgreens/-project-testing-ground/classify/workflow/3506?env=staging&demo=true

[eatyourgreens]

@mcbouslog I can recommend using #2793 for debugging. It adds better console log messages when the store hydrates from a snapshot.

[eatyourgreens]

Fixed in #2813, I think. I'm not seeing this bug when I run Davy Notebooks locally on that branch.

Weird that this bug is specific to Davy Notebooks. I wonder if it is triggered by using many workflows that are all clones of the same step and task structure? Drawing task annotations are stored in store.workflowSteps, in the transcription task model.

[eatyourgreens]

Following on from that comment, should we document the classifier store structure to help in debugging?