Related Field has invalid lookup: icontains

[ian@…]

just upgraded to the latest head, and found this.
I could have sworn it was working beforehand.

Traceback (most recent call last):
File "/home/data/py/django/core/handlers/base.py" in get_response
  74. response = callback(request, *callback_args, **callback_kwargs)
File "/home/data/py/zilbo/common/utils/views/filter.py" in _wrapper
  37. return generic(request, queryset.filter(**filter), *args, **kw)
File "/home/data/py/django/views/generic/list_detail.py" in object_list
  45. object_list = paginator.get_page(page - 1)
File "/home/data/py/django/core/paginator.py" in get_page
  36. object_list = list(self.query_set[offset:offset+limit])
File "/home/data/py/django/db/models/query.py" in __iter__
  103. return iter(self._get_data())
File "/home/data/py/django/db/models/query.py" in _get_data
  430. self._result_cache = list(self.iterator())
File "/home/data/py/django/db/models/query.py" in iterator
  171. select, sql, params = self._get_sql_clause()
File "/home/data/py/django/db/models/query.py" in _get_sql_clause
  444. joins2, where2, params2 = self._filters.get_sql(opts)
File "/home/data/py/django/db/models/query.py" in get_sql
  574. joins2, where2, params2 = val.get_sql(opts)
File "/home/data/py/django/db/models/query.py" in get_sql
  622. return parse_lookup(self.kwargs.items(), opts)
File "/home/data/py/django/db/models/query.py" in parse_lookup
  734. joins2, where2, params2 = lookup_inner(path, lookup_type, value, opts, opts.db_table, None)
File "/home/data/py/django/db/models/query.py" in lookup_inner
  906. params.extend(field.get_db_prep_lookup(lookup_type, value))
File "/home/data/py/django/db/models/fields/related.py" in get_db_prep_lookup
  105. raise TypeError, "Related Field has invalid lookup: %s" % lookup_type

  TypeError at /asset/machine/
  Related Field has invalid lookup: icontains

[Malcolm Tredinnick]

Could you provide an example of what you were doing to trigger this error, please. It is impossible to work it out just from the traceback. A model and a query against it that fails reliably would be nice. Thanks.

[Malcolm Tredinnick]

OK, ignore my last comment, it was lazy. I looked at the code. Suspicion falls on [3246], but it looks like Russell was not expecting non-standard primary keys in there (maybe?). Are you seeing this on a model that has a custom primary key? If not, why on earth are we in that method?

I'm reluctant to go diving in here trying to fix edge cases whilst Adrian is doing his refactoring. The odds of a patch surviving are small. The whole query dissecting and processing phase is possibly open on his lab table with entrails all over the place.

[Ian@…]

Hi.
It was actually an error on my part.. the field it was it is looking at is a generic relation  similar to one in
​http://svn.zyons.python-hosting.com/trunk/zilbo/common/forum/models.py 
class Forum:: summary_tags

but the error looked weird and didn't use to fail in such a way a week or two ago.

[Malcolm Tredinnick]

I'm confused, then. Is this a bug in Django or just a confusing error?

[Chris Beaven]

Closing as Ian stated it was an error on his part. Ian: If there's still a problem with Django that needs to be fixed, please reopen.

[AntonBessonov]

This error raised if use search_fields in admin.py. E.x:

class AnotherModel(models.Model):
  txt = models.CharField(_('Text'), max_length=255)

class MyModel(models.Model):
  prop = models.ForeignKey(AnotherModel)

You must use:

class MyModelAdmin(admin.ModelAdmin):
  search_fields = ('prop__txt')

Maybe must raise properly exception?

[Jeff Blaine]

I'm getting this in 1.3, some 2 years later than the last comment above.

Same situation as above, using Admin. Any search results in the same error as this ticket:

class DeviceAdmin(admin.ModelAdmin):
    search_fields = ['name', 'hardware_arch', 'afs_sysname', 'afs_client_rev', '
propertyno', 'calc_roles', 'notes']

This doesn't work either, where 'hardware_arch' is the only foreign key referenced in search_fields:

class HardwareArchitecture(models.Model):
    name            = models.CharField('Architecture',
                                       primary_key=True,
                                       max_length=40)
#...

class Device(models.Model):
#...
    hardware_arch   = models.ForeignKey(HardwareArchitecture,
                                        blank=True,
                                        null=True,
                                        on_delete=models.DO_NOTHING)

class DeviceAdmin(admin.ModelAdmin):
    search_fields = ['name', 'hardware_arch__name', 'afs_sysname', 'afs_client_r
ev', 'propertyno', 'calc_roles', 'notes']

[Jeff Blaine]

Ignore me. I am an idiot. Fixed. Re-resolving as invalid.

[gmludo@…]

If like me, you're looking for the solution of this error message, this is the documentation : ​https://docs.djangoproject.com/en/dev/ref/contrib/admin/#django.contrib.admin.ModelAdmin.search_fields

[i-am@…]

@gmludo

haha, thanks!

[anonymous]

@gmludo me too, thanks for pointing it out... Uwe

[anonymous]

Thank you.. This problem had really given me some headache