Opened 17 years ago
Closed 17 years ago
#6152 closed (invalid)
django.db.models.Field.to_python not called by QuerySet
Reported by: | Daniel Pope | Owned by: | nobody |
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Component: | Database layer (models, ORM) | Version: | dev |
Severity: | Keywords: | ||
Cc: | Triage Stage: | Unreviewed | |
Has patch: | no | Needs documentation: | no |
Needs tests: | no | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description
The to_python function is intended to convert a database representation to a Python object. In Django SVN this function is not called when Model instances are loaded. In built-in fields this omission no effect because the Python DB-API also has a mapping which, coincidentally, converts to the correct types.
However, for user-defined Fields, to_python must be called or the field is assigned the raw database type.
I wonder if the correct solution is to call obj.validate() (which calls to_python() for all fields) just before yielding the obj in QuerySet.__iter__. This, at least, is how I have patched my installation in order to make user-defined fields work as intended.
There's no bug here. Your custom field subclass is required to handle this. See http://www.djangoproject.com/documentation/custom_model_fields/ for one easy way to do (custom_model_fields.txt in the source tree).