Django recipe: Pretty print objects and querysets

By •

Below you can find a utility I use across Django projects called dprint. It's a simple addition to the excellent pprint library that will spit your Django objects and querysets out as dictionaries. The result is that the data are a bit easier to browse while debugging. Or at least I think so.

The odds that I screwed something up or there's an easier way to do this are pretty high. Feel free to tell me about it.

from django.db.models.query import QuerySet
from pprint import PrettyPrinter

def dprint(object, stream=None, indent=1, width=80, depth=None):
    """
    A small addition to pprint that converts any Django model objects to dictionaries so they print prettier.

    h3. Example usage

        >>> from toolbox.dprint import dprint
        >>> from app.models import Dummy
        >>> dprint(Dummy.objects.all().latest())
         {'first_name': u'Ben',
          'last_name': u'Welsh',
          'city': u'Los Angeles',
          'slug': u'ben-welsh',
    """
    # Catch any singleton Django model object that might get passed in
    if getattr(object, '__metaclass__', None):
        if object.__metaclass__.__name__ == 'ModelBase':
            # Convert it to a dictionary
            object = object.__dict__
    
    # Catch any Django QuerySets that might get passed in
    elif isinstance(object, QuerySet):
        # Convert it to a list of dictionaries
        object = [i.__dict__ for i in object]
        
    # Pass everything through pprint in the typical way
    printer = PrettyPrinter(stream=stream, indent=indent, width=width, depth=depth)
    printer.pprint(object)
en
208