id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
21053	Missing related fields	joshua.fialkoff@…	grue	"I have an application with these 4 models (amongst others):

{{{
#!div style=""font-size: 80%""
Code highlighting:
  {{{#!python
class Note(CaseModel):
    name = models.CharField(max_length=100)
    notes = models.TextField(blank=True)

    @property
    def shortened_notes(self):
        if len(self.notes) > 100:
            return self.notes[:100] + '...'
        return self.notes


class Document(CaseModel):
    name = models.CharField(max_length=100)
    upc = models.CharField(max_length=100, verbose_name=""UPC"")
    file = models.FileField(upload_to=""prvate/documents/"")
    notes = models.TextField(blank=True)

    @property
    def shortened_notes(self):
        if len(self.notes) > 100:
            return self.notes[:100] + '...'
        return self.notes

class NoteAttachTo(AttachTo):
    class Meta:
        verbose_name = 'Attach To'
        verbose_name_plural = 'Attach to'
        unique_together = ('note', 'attach_to_type', 'attach_to_id')

    note = models.ForeignKey(Note)


class DocumentAttachTo(AttachTo):
    class Meta:
        verbose_name = 'Attach To'
        verbose_name_plural = 'Attach to'
        unique_together = ('document', 'attach_to_type', 'attach_to_id')

    document = models.ForeignKey(Document)


  }}}
}}}

`AttachTo` and `CaseModel` are abstract base models with fields that are common to their subclasses. Note that `Note` and `Document` are essentially copies of each other. However, while `Note` has the related field `noteattachto`, `Document` does not have `documentattachto`:

{{{
#!div style=""font-size: 80%""
Code highlighting:
  {{{#!python
In [1]: from cases.models import Note, Document                      

In [2]: Note._meta.get_all_field_names()
Out[2]: ['case', u'id', 'name', 'noteattachto', 'notes']

In [3]: Document._meta.get_all_field_names()
Out[3]: ['case', 'file', u'id', 'name', 'notes', 'upc']
  }}}
}}}

I tried to debug this a bit and added a `print` statement in db/models/options.py - `_fill_related_objects_cache`:

{{{
#!div style=""font-size: 80%""
Code highlighting:
  {{{#!python
        #### Starting on line 438 of db/models/options.py
        # Collect also objects which are in relation to some proxy child/parent of self.
        proxy_cache = cache.copy()
        for klass in get_models(include_auto_created=True, only_installed=False):
            print(self.db_table + ': ' + klass.__name__)
            if not klass._meta.swapped:
                for f in klass._meta.local_fields:
                    ...
  }}}
}}}


The relevant output is below. Note that, when the model cache is being built for `Document`, neither `DocumentAttachTo` or `NoteAttachTo` are available. Those models do, however, become available immediately after ""Validating models..."" is printed to the screen. At this point, I'm not really sure what's going on.

{{{
django_content_type: ContentType
django_content_type: Permission
django_content_type: Group_permissions
django_content_type: Group
django_content_type: User_groups
django_content_type: User_user_permissions
django_content_type: User
django_content_type: Site
django_content_type: Case
django_content_type: Debtor
django_content_type: Claim_debtors
django_content_type: Claim
django_content_type: Note
django_content_type: Document
django_content_type: PartyRole
django_content_type: Party
django_content_type: Contact
django_content_type: CourtProceeding
django_content_type: Session
django_content_type: LogEntry
django_content_type: MigrationHistory
cases_claim: ContentType
cases_claim: Permission
cases_claim: Group_permissions
cases_claim: Group
cases_claim: User_groups
cases_claim: User_user_permissions
cases_claim: User
cases_claim: Site
cases_claim: Case
cases_claim: Debtor
cases_claim: Claim_debtors
cases_claim: Claim
cases_claim: Note
cases_claim: Document
cases_claim: PartyRole
cases_claim: Party
cases_claim: Contact
cases_claim: CourtProceeding
cases_claim: Session
cases_claim: LogEntry
cases_claim: MigrationHistory
cases_document: ContentType
cases_document: Permission
cases_document: Group_permissions
cases_document: Group
cases_document: User_groups
cases_document: User_user_permissions
cases_document: User
cases_document: Site
cases_document: Case
cases_document: Debtor
cases_document: Claim_debtors
cases_document: Claim
cases_document: Note
cases_document: Document
cases_document: PartyRole
cases_document: Party
cases_document: Contact
cases_document: CourtProceeding
cases_document: Session
cases_document: LogEntry
cases_document: MigrationHistory
Validating models...

auth_permission: ContentType
auth_permission: Permission
auth_permission: Group_permissions
auth_permission: Group
auth_permission: User_groups
auth_permission: User_user_permissions
auth_permission: User
auth_permission: Site
auth_permission: Case
auth_permission: Debtor
auth_permission: Claim_debtors
auth_permission: Claim
auth_permission: Note
auth_permission: Document
auth_permission: PartyRole
auth_permission: Party
auth_permission: Contact
auth_permission: CourtProceeding
auth_permission: NoteAttachTo
auth_permission: DocumentAttachTo
auth_permission: Session
auth_permission: LogEntry
auth_permission: MigrationHistory
cases_note: ContentType
cases_note: Permission
cases_note: Group_permissions
cases_note: Group
cases_note: User_groups
cases_note: User_user_permissions
cases_note: User
cases_note: Site
cases_note: Case
cases_note: Debtor
cases_note: Claim_debtors
cases_note: Claim
cases_note: Note
cases_note: Document
cases_note: PartyRole
cases_note: Party
cases_note: Contact
cases_note: CourtProceeding
cases_note: NoteAttachTo
cases_note: DocumentAttachTo
cases_note: Session
cases_note: LogEntry
cases_note: MigrationHistory
}}}"	Uncategorized	closed	Database layer (models, ORM)	1.5	Normal	worksforme			Unreviewed	0	0	0	0	0	0