ValueError: too many values to unpack

[msteidley]

Getting this error when:
following installation instructions,
scaffolding a new flask-diamond application,
logging in as [email protected]

and trying to edit a user:
ValueError: too many values to unpack

[msteidley]

Flask-Diamond 0.5.2rc6

Do I need to install an older version to get this working?

[iandennismiller]

Hmmm... The root cause is that the example application extends the default model.User by adding a "name" field, but the CRUD interface hadn't been updated to reflect this. I thought I fixed this by Flask-Diamond 0.5.2rc6. I'll take another look.

[henryk]

@iandennismiller Are you sure that's the root cause here (sounds more like you're talking about #23). @msteidley didn't give a stack trace, but to me it sounds like they hit pallets-eco/flask-admin#1588 which is a bug in flask-admin that makes it fail with recent versions of sqlalchemy.

Steps to reproduce:

1. In an application created with flask-diamond, do pip install --upgrade -r requirements.txt
2. Log in as admin, open the /admin/ interface, try to edit a User object

Actual results:

• At step 1, SQLAlchemy-1.2.1 is installed.
• At step 2, an exception is raised deep in flask-admin, which ends with

  File "[...]/venv/lib/python3.5/site-packages/flask_admin/contrib/sqla/fields.py", line 255, in get_pk_from_identity
    cls, key = identity_key(instance=obj)
ValueError: too many values to unpack (expected 2)

Workaround:

• Include sqlalchemy==1.2.0b3 into requirements.txt
• pip install --upgrade -r requirements.txt will downgrade the sqlalchemy version to one that still works with flask-admin