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Class has no objects member

python
pylint
django
orm
Anton ShumikhinbyAnton Shumikhin·Aug 27, 2024
TLDR

If you're battling the "Class has no objects member" message, don't fret. This occurs due to dynamic attribute creation in ORMs like Django or SQLAlchemy. One quick solution is to integrate ORM-specific linter plugins, like pylint-django for Django. Here's how you do it:

pip install pylint-django pylint --load-plugins pylint_django your_model_file.py

And for SQLAlchemy, use pylint-sqlalchemy directly. If a plugin is not an option for you, you can suppress the linter warning with a comment:

# pylint: disable=no-member

To tailor this more to your .pylintrc and ignore these ORM classes, go ahead with:

[TYPECHECK] ignored-classes=ModelClassName

Also, to enhance Visual Studio Code (VSC) with pylint-django, have the following line in your VSC settings:

"pylint.args": ["--load-plugins=pylint_django"]

Setting Pylint to recognize Django

Introducing the Database Manager

Every Django model comes equipped with a default database manager named objects. If you're getting warnings, you may just have to explicitly tell your model that it's there:

class Question(models.Model): # Define the manager if not already there objects = models.Manager()

This helps Pylint and other linters or IDEs recognize the manager.

Loading up the Pylint bandwagon

pylint-django extends Pylint with some Django goodness. After installing with pip, you need to update your settings in your IDE to ensure that they're aware this new band member:

// In your settings.json in Visual Studio Code { "python.linting.pylintArgs": [ "--load-plugins=pylint_django" ] }

Troubleshooting the Configuration

Check for typos or incorrect syntax in your settings.json. As a general rule, ensure all configurations are cocooned in curly braces {} and the square type [].

A closer look

Decrypting the Error Message

"Beware: molecules at work!" This warning is due to:

  1. It's a common false-positive error due to static analysis tools.
  2. Because of the dynamic nature of managing database schema objects.
  3. Most likely with ORMs creating attributes at runtime, leaving static checks in the dust.

Handling False-Positives

"No battle plan ever survived contact with the enemy." Beyond this General Helmuth von Moltke quote, here's how to tackle false-positive warnings:

  1. Use ORM-specific plugins for your linter.
  2. Adjust your settings to skip specific checks.
  3. Add inline comments in your code using pylint convention to hush specific warnings.

Continuous Learning and Community Support

You can always dive into threads in Reddit or Stack Overflow to check how others have wrangled these warnings. Don't skip official documentation for a deeper understanding of design patterns and some effective troubleshooting tips.