我想将默认值从 django 1.8 传递到 DurationField。根据文档,它应该是 datetime.timedelta
from datetime import timedelta
pause = DurationField(default=timedelta(minutes=20))
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但是在 makemigrations 上它说:
ValueError: Cannot serialize: datetime.timedelta(0, 1200)
There are some values Django cannot serialize into migration files.
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好的。也许我们应该传递整数?
pause = DurationField(default=int(timedelta(minutes=20).total_seconds()))
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或者:
pause = DurationField(default=20*60)
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makemigrations 运行正常,但在创建对象时我看到:
for obj in self.query.objs
File "/home/web/django_env/lib/python3.4/site-packages/django/db/models/sql/compiler.py", line 920, in <listcomp>
for obj in self.query.objs
File "/home/web/django_env/lib/python3.4/site-packages/django/db/models/sql/compiler.py", line 918, in <listcomp>
) for f in fields
File "/home/web/django_env/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 710, in get_db_prep_save
prepared=False)
File "/home/web/django_env/lib/python3.4/site-packages/django/db/models/fields/__init__.py", line 1683, in get_db_prep_value
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