Django

Question

我正在尝试使用 factory boy 生成虚假条目，但我遇到了与布尔字段相关的问题。

遵循模型和模型工厂：

# models.py

class Record(models.Model):
    date_creation = models.DateTimeField()
    rec_type = models.CharField(max_length=1, choices=RECORD_TYPES)
    direction = models.BooleanField()

# factories.py

class RecordFactory(DjangoModelFactory):

    class Meta:
        model = Record

    date_creation = factory.Faker('date_time')
    rec_type = factory.Faker('random_choices', elements=[x[1] for x in Record.RECORD_TYPES])
    direction = factory.Faker('pybool')

如何解决这个问题？好像跟boolean字段有关。

/usr/local/lib/python3.7/site-packages/django/db/models/fields/__init__.py:1427: RuntimeWarning: DateTimeField Record.date_creation received a naive datetime (1
977-11-24 14:21:26) while time zone support is active.
  RuntimeWarning)
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
psycopg2.errors.StringDataRightTruncation: value too long for type character varying(1)


The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "manage.py", line 30, in <module>   
    execute_from_command_line(sys.argv)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/__init__.py", line 381, in execute_from_command_line
    utility.execute()
  File "/usr/local/lib/python3.7/site-packages/django/core/management/__init__.py", line 375, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/base.py", line 323, in run_from_argv
    self.execute(*args, **cmd_options)
  File "/usr/local/lib/python3.7/site-packages/django/core/management/base.py", line 364, in execute
    output = self.handle(*args, **options) 
File "/app/iur/core/management/commands/seed.py", line 60, in handle
    self.create(options["records"], RecordFactory)
  File "/app/iur/core/management/commands/seed.py", line 47, in create
    factory_class.create()
  File "/usr/local/lib/python3.7/site-packages/factory/base.py", line 564, in create
    return cls._generate(enums.CREATE_STRATEGY, kwargs)
  File "/usr/local/lib/python3.7/site-packages/factory/django.py", line 141, in _generate
    return super(DjangoModelFactory, cls)._generate(strategy, params)
  File "/usr/local/lib/python3.7/site-packages/factory/base.py", line 501, in _generate
    return step.build()
  File "/usr/local/lib/python3.7/site-packages/factory/builder.py", line 279, in build
    kwargs=kwargs,
  File "/usr/local/lib/python3.7/site-packages/factory/base.py", line 315, in instantiate
    return self.factory._create(model, *args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/factory/django.py", line 185, in _create
    return manager.create(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/query.py", line 422, in create
    obj.save(force_insert=True, using=self.db)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/base.py", line 741, in save
    force_update=force_update, update_fields=update_fields)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/base.py", line 779, in save_base
    force_update, using, update_fields,
  File "/usr/local/lib/python3.7/site-packages/django/db/models/base.py", line 870, in _save_table
    result = self._do_insert(cls._base_manager, using, fields, update_pk, raw)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/base.py", line 908, in _do_insert
    using=using, raw=raw)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/query.py", line 1186, in _insert
    return query.get_compiler(using=using).execute_sql(return_id)
  File "/usr/local/lib/python3.7/site-packages/django/db/models/sql/compiler.py", line 1335, in execute_sql
    cursor.execute(sql, params)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 99, in execute
    return super().execute(sql, params)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 67, in execute
    return self._execute_with_wrappers(sql, params, many=False, executor=self._execute)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 76, in _execute_with_wrappers
    return executor(sql, params, many, context)
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
  File "/usr/local/lib/python3.7/site-packages/django/db/utils.py", line 89, in __exit__
    raise dj_exc_value.with_traceback(traceback) from exc_value
  File "/usr/local/lib/python3.7/site-packages/django/db/backends/utils.py", line 84, in _execute
    return self.cursor.execute(sql, params)
django.db.utils.DataError: value too long for type character varying(1)

Answer 1

只需设置例如direction = False 在 RecordFactory 中。或者，如果你想使用 faker，你可以做 direction = Faker().pybool()

我认为该错误告诉您您的数据库后端使用单字母 varchar 来表示布尔值（很可能是 "t" 和 "f"）。

Answer 2

可能不是导致错误的布尔字段，而是

rec_type = models.CharField(max_length=1, choices=RECORD_TYPES)

因为它的max_length是1。你能确认RECORD_TYPES最多1个字符吗？

django.db.utils.DataError: value too long for type character varying(1)

这应该表明它是最大长度为 1 的 VARCHAR。从跟踪中可以看出，您的数据库后端是 postgres，其中有一个本机布尔字段。

Answer 3

主要问题是我用错了 Faker。这个达到了我的预期：

# factories.py

...

rec_type = factory.Faker('random_element', elements=[x[0] for x in Record.RECORD_TYPES])

...

Django | Factory boy | faking a boolean field | django.db.utils.DataError: value too long for type character varying(1)

Django | Factory boy | faking a boolean field | django.db.utils.DataError: value too long for type character varying(1)

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