entityMap|blocks|key|8sk4l|text|AFAIK，这是因为向后兼容。ModelForms中排除的字段、具有默认值的模型、pre等也存在问题|type|unstyled|depth|inlineStyleRanges|entityRanges|data|9eg1m|_|7fs9l|save()信号等。|bvug0|您可能感兴趣的来源：|esbj2|http://code.djangoproject.com/ticket/13100|d6fsb|http://groups.google.com/group/django-developers/browse|2qvu0|4024p|frm/thread/b888734b05878f87^0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|P|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|Q|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|R|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|S|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|T|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|U|9|@]|A|@]|B|$]]|$2|M|4|D|6|7|8|V|9|@]|A|@]|B|$]]|$2|N|4|O|6|7|8|W|9|@]|A|@]|B|$]]]]

AFAIK, this is because of backwards compatibility. There are also problems with ModelForms with excluded fields, models with default values, pre_save() signals, etc.

Sources you might be intrested in:

<ul>
<li><a href="http://code.djangoproject.com/ticket/13100" rel="noreferrer">http://code.djangoproject.com/ticket/13100</a></li>
<li><a href="http://groups.google.com/group/django-developers/browse_frm/thread/b888734b05878f87" rel="noreferrer">http://groups.google.com/group/django-developers/browse_frm/thread/b888734b05878f87</a></li>
</ul>

entityMap|blocks|key|du37a|text|由于兼容性的考虑，在django内核中没有启用保存时自动清除。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|ri0m|如果我们正在启动一个新项目，并且想要缺省的|1i71e|模型上的方法可以自动清理，我们可以在保存每个模型之前使用以下信号进行清理。|abj2a|from+django.dispatch+import+receiver
from+django.db.models.signals+import+pre_save,+post_save

@receiver(pre_save)
def+pre_save_handler(sender,+instance,+*args,+**kwargs):
++++instance.full_clean()|code-block|syntax|javascript^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|M|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|N|9|@]|A|@]|B|$]]|$2|G|4|H|6|I|8|O|9|@]|A|@]|B|$J|K]]]]

Because of the compatibility considering, the auto clean on save is not enabled in django kernel.

If we are starting a new project and want the default <code>save</code> method on Model could clean automatically, we can use the following signal to do clean before every model was saved. 

<pre><code>from django.dispatch import receiver
from django.db.models.signals import pre_save, post_save

@receiver(pre_save)
def pre_save_handler(sender, instance, *args, **kwargs):
 instance.full_clean()
</code></pre>

entityMap|blocks|key|dcm11|text|我们可以像下面这样使用应用程序，而不是插入一段声明接收器的代码|type|unstyled|depth|inlineStyleRanges|entityRanges|data|fn766|中的部分|8acet|INSTALLED_APPS+=+[
++++#+...
++++'django_fullclean',
++++#+your+apps+here,
]|code-block|syntax|javascript|d8e01|在此之前，您可能需要安装|b13si|使用PyPI：|cbiv9|pip+install+django-fullclean^0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|P|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|Q|9|@]|A|@]|B|$]]|$2|E|4|F|6|G|8|R|9|@]|A|@]|B|$H|I]]|$2|J|4|K|6|7|8|S|9|@]|A|@]|B|$]]|$2|L|4|M|6|7|8|T|9|@]|A|@]|B|$]]|$2|N|4|O|6|G|8|U|9|@]|A|@]|B|$H|I]]]]

Instead of inserting a piece of code that declares a receiver, we can use an app as <code>INSTALLED_APPS</code> section in <code>settings.py</code>

<pre><code>INSTALLED_APPS = [
 # ...
 'django_fullclean',
 # your apps here,
]
</code></pre>

Before that, you may need to install <a href="https://pypi.org/project/django-fullclean/" rel="nofollow noreferrer"><code>django-fullclean</code></a> using PyPI:

<pre><code>pip install django-fullclean
</code></pre>

entityMap|blocks|key|5cu8s|text|调用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|7bv26|方法只是重写|4jjtt|方法：|dv5c6|class+YourModel(models.Model):
++++...++
++++
++++def+save(self,+*args,+**kwargs):
++++++++self.full_clean()
++++++++return+super(YourModel,+self).save(*args,+**kwargs)|code-block|syntax|javascript^0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|L|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|M|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|N|9|@]|A|@]|B|$]]|$2|G|4|H|6|I|8|O|9|@]|A|@]|B|$J|K]]]]

The simplest way to call the <code>full_clean</code> method is just to override the <code>save</code> method in your model:
<pre><code>class YourModel(models.Model):
 ... 
 
 def save(self, *args, **kwargs):
 self.full_clean()
 return super(YourModel, self).save(*args, **kwargs)
</code></pre>

entityMap|blocks|key|b6au3|text|如果您希望确保模型至少具有一个FK关系，但您不想使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|c54oj|因为这需要设置一个默认的FK+(可能是垃圾数据)，所以我想出的最好的方法是添加自定义|b988s|和|2m5uu|方法。|f0k90|引发验证错误，并|c74p0|叫清洁工。这样，就可以从表单和其他调用代码、命令行和测试中强制执行完整性。如果没有这一点，(AFAICT)就没有办法编写测试来确保模型与特定选择(而不是默认)的其他模型具有FK关系。|ftsn0|class+Payer(models.Model):

++++name+=+models.CharField(blank=True,+max_length=100)
++++#+Nullable,+but+will+enforce+FK+in+clean/save:
++++payer_group+=+models.ForeignKey(PayerGroup,+null=True,+blank=True,)

++++def+clean(self):
++++++++#+Ensure+every+Payer+is+in+a+PayerGroup+(but+only+via+forms)
++++++++if+not+self.payer_group:
++++++++++++raise+ValidationError(
++++++++++++++++{'payer_group':+'Each+Payer+must+belong+to+a+PayerGroup.'})

++++def+save(self,+*args,+**kwargs):
++++++++self.full_clean()
++++++++return+super().save(*args,+**kwargs)

++++def+__str__(self):
++++++++return+self.name|code-block|syntax|javascript^0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|R|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|S|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|T|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|U|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|V|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|W|9|@]|A|@]|B|$]]|$2|M|4|N|6|O|8|X|9|@]|A|@]|B|$P|Q]]]]

If you have a model that you want to ensure has at least one FK relationship, and you don't want to use <code>null=False</code> because that requires setting a default FK (which would be garbage data), the best way I've come up with is to add custom <code>.clean()</code> and <code>.save()</code> methods. <code>.clean()</code> raises the validation error, and <code>.save()</code> calls the clean. This way the integrity is enforced both from forms and from other calling code, the command line, and tests. Without this, there is (AFAICT) no way to write a test that ensures that a model has a FK relation to a specifically chosen (not default) other model.

<pre><code>class Payer(models.Model):

 name = models.CharField(blank=True, max_length=100)
 # Nullable, but will enforce FK in clean/save:
 payer_group = models.ForeignKey(PayerGroup, null=True, blank=True,)

 def clean(self):
 # Ensure every Payer is in a PayerGroup (but only via forms)
 if not self.payer_group:
 raise ValidationError(
 {'payer_group': 'Each Payer must belong to a PayerGroup.'})

 def save(self, *args, **kwargs):
 self.full_clean()
 return super().save(*args, **kwargs)

 def __str__(self):
 return self.name
</code></pre>

entityMap|blocks|key|9u1uq|text|评论@Alfred+Huang的回答和评论。用户可能会锁定pre|type|unstyled|depth|inlineStyleRanges|entityRanges|data|tfog|_|1ishm|通过在当前模块(models.py)中定义类的列表并在pre中对其进行检查来保存钩子到应用程序|evliv|esdm5|保存挂钩：|d6p60|CUSTOM_CLASSES+=+[obj+for+name,+obj+in
++++++++inspect.getmembers(sys.modules[__name__])
++++++++if+inspect.isclass(obj)]

@receiver(pre_save)
def+pre_save_handler(sender,+instance,+**kwargs):
++++if+type(instance)+in+CUSTOM_CLASSES:
++++++++instance.full_clean()|code-block|syntax|javascript^0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|O|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|P|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|Q|9|@]|A|@]|B|$]]|$2|G|4|D|6|7|8|R|9|@]|A|@]|B|$]]|$2|H|4|I|6|7|8|S|9|@]|A|@]|B|$]]|$2|J|4|K|6|L|8|T|9|@]|A|@]|B|$M|N]]]]

Commenting on @Alfred Huang's answer and coments on it. One might lock the pre_save hook down to an app by defining a list of classes in the current module (models.py) and checking against it in the pre_save hook:

<pre><code>CUSTOM_CLASSES = [obj for name, obj in
 inspect.getmembers(sys.modules[__name__])
 if inspect.isclass(obj)]

@receiver(pre_save)
def pre_save_handler(sender, instance, **kwargs):
 if type(instance) in CUSTOM_CLASSES:
 instance.full_clean()
</code></pre>

entityMap|blocks|key|d4a77|text|全球|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1hlht|如果您希望始终确保模型验证，signal可以很好地工作。然而，它将在当前版本(3.1.x)中遇到Django的身份验证问题，并可能导致您正在使用的其他应用程序的模型出现问题。|87dv3|详细阐述@Peter+Shannon的答案，这个版本将只验证您在其中执行它的模块内的模型，跳过验证|rula|“原始”保存|3qdep|并添加一个|9vqsb|至|2t4sl|避免重复信号|bdhdb|..。|836k2|from+django.db.models.signals+import+pre_save
import+inspect
import+sys

MODELS+=+[obj+for+name,+obj+in
++++inspect.getmembers(sys.modules[__name__],+inspect.isclass)]

def+validate_model(sender,+instance,+**kwargs):
++++if+'raw'+in+kwargs+and+not+kwargs['raw']:
++++++++if+type(instance)+in+MODELS:
++++++++++++instance.full_clean()

pre_save.connect(validate_model,+dispatch_uid='validate_models')|code-block|syntax|javascript^0|0|0|0|0|0|0|0|0^^$0|$]|1|@$2|3|4|5|6|7|8|V|9|@]|A|@]|B|$]]|$2|C|4|D|6|7|8|W|9|@]|A|@]|B|$]]|$2|E|4|F|6|7|8|X|9|@]|A|@]|B|$]]|$2|G|4|H|6|7|8|Y|9|@]|A|@]|B|$]]|$2|I|4|J|6|7|8|Z|9|@]|A|@]|B|$]]|$2|K|4|L|6|7|8|10|9|@]|A|@]|B|$]]|$2|M|4|N|6|7|8|11|9|@]|A|@]|B|$]]|$2|O|4|P|6|7|8|12|9|@]|A|@]|B|$]]|$2|Q|4|R|6|S|8|13|9|@]|A|@]|B|$T|U]]]]

A global <code>pre_save</code> signal can work well if you want to always ensure model validation. However it will run into issues with Django's auth in current versions (3.1.x) and could cause issues with models from other apps you are using.
Elaborating on @Peter Shannon's answer, this version will only validate models inside the module you execute it in, skips validation with <a href="https://docs.djangoproject.com/en/3.1/ref/signals/#pre-save" rel="nofollow noreferrer">&quot;raw&quot; saves</a> and adds a <code>dispatch_uid</code> to <a href="https://docs.djangoproject.com/en/3.1/topics/signals/#preventing-duplicate-signals" rel="nofollow noreferrer">avoid duplicate signals</a>.
<pre class="lang-py prettyprint-override"><code>from django.db.models.signals import pre_save
import inspect
import sys

MODELS = [obj for name, obj in
 inspect.getmembers(sys.modules[__name__], inspect.isclass)]

def validate_model(sender, instance, **kwargs):
 if 'raw' in kwargs and not kwargs['raw']:
 if type(instance) in MODELS:
 instance.full_clean()

pre_save.connect(validate_model, dispatch_uid='validate_models')
</code></pre>

I'm just curious if anyone knows if there's good reason why django's orm doesn't call 'full_clean' on a model unless it is being saved as part of a model form. 

<blockquote>
 Note that full_clean() will not be called automatically when you call your model’s save() method. You’ll need to call it manually when you want to run one-step model validation for your own manually created models.
 <a href="http://docs.djangoproject.com/en/dev/ref/models/instances/?from=olddocs#django.db.models.Model.full_clean">django's full clean doc</a>
</blockquote>

(NOTE: quote updated for Django 1.6... previous django docs had a caveat about ModelForms as well.)

Are there good reasons why people wouldn't want this behavior? I'd think if you took the time to add validation to a model, you'd want that validation run every time the model is saved.

I know how to get everything to work properly, I'm just looking for an explanation.

Why doesn't django's model.save() call full_clean()?

身份验证

Django

 我只是好奇有没有人知道为什么django的orm没有调用“full” _ 在模型上进行清理，除非将其保存为模型表单的一部分。 请注意，完整的 _ 当您调用模型的save()方法时，clean()不会自动调用。当您想要为自己手动创建的模型运行一步模型验证时，您需要手动调用它。 django的完整干净文档   (注: D...

问为什么django的model.save()不调用full_clean()？
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问为什么django的model.save()不调用full_clean()？
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