Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
 Reporter:  Dennis Kaarsemaker   |Owner:  nobody
 Type:  Bug  |   Status:  closed
Component:  Database layer   |  Version:  master
  (models, ORM)  |   Resolution:  fixed
 Severity:  Normal   | Triage Stage:  Accepted
 Keywords:   |  Needs documentation:  0
Has patch:  1|  Patch needs improvement:  1
  Needs tests:  0|UI/UX:  0
Easy pickings:  0|
-+-
Changes (by aaugustin):

 * status:  new => closed
 * resolution:   => fixed


Comment:

 This is "fixed" by the app-loading refactor, in the sense that you get a
 `RuntimeError: App registry isn't ready yet.` with this definition of
 models. Making SQL queries at import time has never worked correctly.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to django-updates+unsubscr...@googlegroups.com.
To post to this group, send email to django-updates@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/django-updates/076.6646926d8ffd5c5c54e33f2523725edd%40djangoproject.com.
For more options, visit https://groups.google.com/d/optout.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |  Owner:  nobody
  Kaarsemaker| Status:  new
   Type:  Bug|  Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN|   Severity:  Normal
 Resolution: |   Keywords:
   Triage Stage:  Accepted   |  Has patch:  1
Needs documentation:  0  |Needs tests:  0
Patch needs improvement:  1  |  Easy pickings:  0
  UI/UX:  0  |
-+-
Changes (by kmtracey):

 * ui_ux:   => 0


Old description:

> Ok, that sounds vague but I don't know how to better describe it.
> Basically it boils down to having this in models.py:
>
> {{{
> from django.db import models
> import os
>
> class c1(models.Model):
> name = models.CharField("Name", max_length=30)
>
> default_c1 = c1.objects.get(name="non_existant")
>
> class c2(models.Model):
> other = models.ForeignKey(c1, default=default_c1)
> }}}
>
> Querying c1 later with c1.objects.filter(c2__pk=0) will fail:
> FieldError: Cannot resolve keyword 'c2' into field. Choices are: id, name
>
> Minimal testcase project attached (models.py is slightly bigger than
> above). You can reproduce the problem with:
>
> {{{
> # Create the database (clobbers test.db in the current dir)
> ./manage.py syncdb
> # See that without querying in between it works
> echo -e "from proj1.app1.models import c1\nc1.objects.filter(c2__pk=0)" |
> ./manage.py shell
> # See that with querying in between it fails
> echo -e "from proj1.app1.models import c1\nc1.objects.filter(c2__pk=0)" |
> BREAK_ME=1 ./manage.py shell
> }}}
>
> Found on 1.0.2, confirmed with trunk (fresh checkout, less than 30
> minutes ago)

New description:

 Ok, that sounds vague but I don't know how to better describe it.
 Basically it boils down to having this in models.py:

 {{{
 from django.db import models
 import os

 class c1(models.Model):
 name = models.CharField("Name", max_length=30)

 default_c1 = c1.objects.get(name="non_existant")

 class c2(models.Model):
 other = models.ForeignKey(c1, default=default_c1)
 }}}

 Querying c1 later with `c1.objects.filter(c2__pk=0)` will fail:
 {{{
 FieldError: Cannot resolve keyword 'c2' into field. Choices are: id, name
 }}}
 Minimal testcase project attached (models.py is slightly bigger than
 above). You can reproduce the problem with:

 {{{
 # Create the database (clobbers test.db in the current dir)
 ./manage.py syncdb
 # See that without querying in between it works
 echo -e "from proj1.app1.models import c1\nc1.objects.filter(c2__pk=0)" |
 ./manage.py shell
 # See that with querying in between it fails
 echo -e "from proj1.app1.models import c1\nc1.objects.filter(c2__pk=0)" |
 BREAK_ME=1 ./manage.py shell
 }}}

 Found on 1.0.2, confirmed with trunk (fresh checkout, less than 30 minutes
 ago)

--

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |  Owner:  nobody
  Kaarsemaker| Status:  new
   Type:  Bug|  Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN|   Severity:  Normal
 Resolution: |   Keywords:
   Triage Stage:  Accepted   |  Has patch:  1
Needs documentation:  0  |Needs tests:  0
Patch needs improvement:  1  |  Easy pickings:  0
-+-
Changes (by ramiro):

 * easy:  1 => 0


-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |  Owner:  nobody
  Kaarsemaker| Status:  new
   Type:  Bug|  Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN|   Severity:  Normal
 Resolution: |   Keywords:
   Triage Stage:  Accepted   |  Has patch:  1
Needs documentation:  0  |Needs tests:  0
Patch needs improvement:  1  |  Easy pickings:  1
-+-
Changes (by zuko):

 * easy:  0 => 1


-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |  Owner:  nobody
  Kaarsemaker| Status:  new
   Type:  Bug|  Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN|   Severity:  Normal
 Resolution: |   Keywords:
   Triage Stage:  Accepted   |  Has patch:  1
Needs documentation:  0  |Needs tests:  0
Patch needs improvement:  1  |  Easy pickings:  0
-+-
Changes (by zuko):

 * cc: zuko (added)
 * easy:   => 0


-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |Owner:  nobody
  Kaarsemaker|   Status:  new
   Type:  Bug|Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN| Severity:  Normal
 Resolution: | Keywords:
   Triage Stage:  Accepted   |Has patch:  1
Needs documentation:  0  |  Needs tests:  0
Patch needs improvement:  1  |
-+-
Changes (by julien):

 * needs_better_patch:  0 => 1


Comment:

 The tests would need to be rewritten using unittests since this is now
 Django's preferred way. Also there seems to be multiple directions
 suggested for fixing this issue. One needs to clarify which approach suits
 best.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
-+-
   Reporter:  Dennis |Owner:  nobody
  Kaarsemaker|   Status:  new
   Type:  Bug|Component:  Database layer
  Milestone: |  (models, ORM)
Version:  SVN| Severity:  Normal
 Resolution: | Keywords:
   Triage Stage:  Accepted   |Has patch:  1
Needs documentation:  0  |  Needs tests:  0
Patch needs improvement:  0  |
-+-

Comment (by kmtracey):

 #15771 looks like another case of this error, now triggered by importing
 from `contrib.auth.admin` before defining a model with a relationship to
 User -- something that used (1.2.X) to work. Not sure what has changed
 that it now (1.3) triggers this error.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Changes (by josephdrose):

 * cc: jr...@morristechnology.com (added)

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-upda...@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Comment (by josephdrose):

 I've upload a patch that rebuilds the cache if there is a key error in the
 options class.  This should fix any instances where bad cache values cause
 a key error; also, there is minimal performance hit, as once a good cache
 is built, it is used.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

-- 
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-upda...@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Comment (by seveas):

 I retract this ticket, I just found that this creates issues elsewhere as
 well, which cannot be solved this easily. A warning in the docs about not
 doing models.py-level queries or mixing forms and models would be
 appreciated though.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.

--

You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-upda...@googlegroups.com.
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com.
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en.

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Comment (by seveas):

 #11247 is a different manifestation of this bug, which is more likely to
 occur.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Changes (by seveas):

  * needs_tests:  1 => 0

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  1 
Needs_better_patch:  0 |  
---+
Comment (by Dennis Kaarsemaker):

 Updated patch: fixing del(), adding comments and adding a test case.
 ./runtests.py -v2 query_between_definitions fails without the (rest of
 the) patch applied and succeeds otherwise. I cheated a little bit by not
 actually running a query, but the calling init_name_map(). This is the bit
 that actually causes the problem and running a query would call this
 function too.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  1 
Needs_better_patch:  0 |  
---+
Comment (by Alex):

 1) Yeah, I understand, but we try to follow PEP8 where possible.

 3) Here are the docs on Django's test framework:
 http://docs.djangoproject.com/en/dev/topics/testing/?from=olddocs#writing-
 tests, here's some info on getting setup to run the test suite:
 http://lazypython.blogspot.com/2008/11/running-django-test-suite.html,
 lastly take a look at the tests/regressiontests directory of the source.
 Each directory in there is a set of self contained tests.  However, the
 nature of this problem makes me think it will be very difficult to tests,
 so if it seems impossible I wouldn't waste a ton of time on it.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  1 
Needs_better_patch:  0 |  
---+
Comment (by Dennis Kaarsemaker):

 1. That's my coding style slipping though, will fix
 2. I followed the style in get_all_related_objects_with_model, but agree
 that a hasattr() reads better.
 3. I'm very unfamiliar with django's test setup. Can you point me to some
 documentation?

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Accepted  | Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  1 
Needs_better_patch:  0 |  
---+
Changes (by Alex):

  * needs_tests:  0 => 1
  * stage:  Unreviewed => Accepted

Comment:

 Couple things:
 1. del is a statement, so no need for the parentheses
 2. I think the patch reads a little better as a hasattr() test instead of
 catching the exception.  Also put a comment next to each of these saying
 if the cache is populated we clear it out because it needs to be
 repopulated to include the attr we're about to assign.
 3. Can you put a testcase in the Django tests that demonstrates that this
 has been fixed.

 Otherwise the patch looks good to me.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Unreviewed| Has_patch:  1 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Changes (by Dennis Kaarsemaker):

  * has_patch:  0 => 1

Comment:

 Attached patch clears the relevant _related_*_cache in
 contribute_to_related_class of OneToOneField, ManyToManyField and
 ForeignKey. This makes new relationships visible even if a query that
 triggers filling this cache has been executed beforehand. Tested against
 the test project (and another, proprietary, one).

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---

Re: [Django] #11448: Defining relationships after querying a model does not add a reverse lookup to the referenced model

[Django]

#11448: Defining relationships after querying a model does not add a reverse 
lookup
to the referenced model
---+
  Reporter:  Dennis Kaarsemaker| Owner:  nobody
Status:  new   | Milestone:
 Component:  Database layer (models, ORM)  |   Version:  SVN   
Resolution:|  Keywords:
 Stage:  Unreviewed| Has_patch:  0 
Needs_docs:  0 |   Needs_tests:  0 
Needs_better_patch:  0 |  
---+
Changes (by Dennis Kaarsemaker):

  * needs_better_patch:  => 0
  * needs_tests:  => 0
  * needs_docs:  => 0

Comment:

 Manually deleting the _related_objects_cache (and for good measure the
 _related_many_to_many_cache) works around the problem. I'd rather see
 django do that when defining a new model. Patch to follow soon.

-- 
Ticket URL: 
Django 
The Web framework for perfectionists with deadlines.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups 
"Django updates" group.
To post to this group, send email to django-updates@googlegroups.com
To unsubscribe from this group, send email to 
django-updates+unsubscr...@googlegroups.com
For more options, visit this group at 
http://groups.google.com/group/django-updates?hl=en
-~--~~~~--~~--~--~---