Django：为什么我的“save_model()”不起作用？

Question

如果有人能帮我解决我的编码问题，我将非常非常感激。当我在管理界面中时，不会产生任何错误。但是，当我在管理界面下为 Provider 对象单击“保存”时，我在自定义 save_model(...) 函数下指定的任何内容似乎都没有执行。我已经将我的代码压缩成小快照。 我做错了什么？

旁注：这听起来可能很奇怪，但我也在尝试在保存过程中删除该对象（在这样做之前它应该覆盖另一个“提供者”对象）。

====================

model.py

#models.py
...
class Provider(models.Model):  
  title = models.CharField(max_length=150)
  purpose = models.TextField()
  summary = models.TextField()
  email = models.EmailField()
  access_code = models.CharField(max_length=30, default=random_password)
  verified = models.BooleanField(default=False) #On/Off switch to display on database
  flagged = models.BooleanField(default=False) 
  revised = models.BooleanField(verbose_name = "New Update", default=False)
    # Will be True, if a revision has occured
        # On/Off switch state whether this is a revision of an existing Provider
    # This will be useful for creating a manager that lists updated providers
    # Note: Must delete Revised_Provider object after verification is complete
    # and UPDATE has occurred on save()

  #M2M Relations
  serviced_location = models.ManyToManyField(Location, through='ServicedLocations')
  services_offered = models.ManyToManyField(ServiceType, through='OfferedServices')
  insurances_accepted = models.ManyToManyField(InsuranceProvider, through='AcceptedInsurances')
  #contacts = models.ManyToManyField(Contact, blank=True)

  def __unicode__(self):
    return self.title

#Used for allow the provider to make change to their profile, and wait
#for verification before it will show up on regular search results
#Serves as a map for referencing a verified provider to a recent update (revision)
class Revision(models.Model): #Revised Providers (eg: Updated)
  provider = models.ForeignKey(Provider, null=True)
  date_revised = models.DateTimeField(auto_now=True, auto_now_add=True)
  def __unicode__(self):
      return u'%s' % self.provider

class ServicedLocations(models.Model):
  location = models.ForeignKey(Location)
  provider = models.ForeignKey(Provider) #Pre-Verified or Verified Settings
  revision = models.ForeignKey(Revision, null=True, on_delete=models.SET_NULL)
...etc...

====================

admin.py

#admin.py
from django.contrib import admin
from django.forms.models import ModelForm
from django import forms
from health.providers.models import *
class ProviderAdminForm(forms.ModelForm):
    def clean(self):
        cleaned_data = self.cleaned_data
        flagged = cleaned_data.get("flagged")
        verified = cleaned_data.get("verified")

        if flagged == True and verified == True:
        raise forms.ValidationError("You cannot verify a 'flagged' provider. If you meant to verify this provider, be sure to uncheck 'flagged'")
               # Just in case someone accidently verified a flagged provider       
        return cleaned_data

class ProviderAdmin(admin.ModelAdmin):    
    list_per_page = 100
    list_display = ('date_added', 'title', 'state', 'verified', 'flagged')
    list_display_links = ('title',)
    list_filter = ('verified', 'flagged', 'revised')
    search_fields = ['title',]
    filter_horizontal = ('services_offered',)
    form = ProviderAdminForm

    def save_model(self, request, obj, form, change):
        ProviderID = obj.id
        try: #see if a revision exists in the table
            Compare = Revision.objects.get(id=ProviderID)

            OldProviderID = Compare.provider.id
            OldProvider = Provider.objects.get(id=OldProviderID)

            RevisedProvider = Provider.objects.get(id=ProviderID) 
            RevisedProviderID = RevisedProvider.id

            if change:  #Check to see if we changed anything important
                verified = form.cleaned_data['verified']
                #Means we would have had to manually verified it

                if verified == True: 
                #This means that we have approved to update the old Provider
                #After copying the data over, we destroy what we are saving

                    obj.revised = False
                    obj.save()
                    #If we verfied it, revised = False  

                    OldProvider = RevisedProvider #Update Existing Provider Table
                    OldProvider.save()


                    NewLocations = ServicedLocations.objects.get(provider=RevisedProviderID)
                    OldLocations = ServicedLocations.objects.get(provider=OldProviderID)
                    OldLocations = NewLocations
                    OldLocations.save()
                    NewLocations.delete()


                    Compare.delete() #Delete from database
                    RevisedProvider.delete() #Delete Final Copy of Table

                    return HttpResponseRedirect("admin/providers/provider/%s/" % OldProviderID) #Redirect them to updated provider

        except Revision.DoesNotExist:
         print "This provider does not have any unverified revisions"

        return super(ProviderAdmin, self).save_model(request, obj, form, change)       

admin.site.register(Provider, ProviderAdmin)

Answer 1

代码在哪里弹出？你是说它根本不会执行？甚至没有在第一行记录语句？或者您是说数据库中没有进行您预期的更改？

我尝试用各种理论重现您的情况，但无法重现问题。你能更详细地描述问题是什么吗？尝试做一些 pdb.set_trace()，挖掘并给我们更多细节：)

由于您没有提供例外情况，因此您需要提供有关问题所在的更多信息。

PS：我正在阅读您的代码，但很难阅读！类看起来像看起来像变量的实例......只是提醒一下，它违反了 Python 的编码约定，正如您使用语法突出显示所看到的那样，认为您的 CapitalizedObjects 是类。

---

看起来您正在保存主对象，多次更改其引用名称，然后再次保存，然后将其删除！这里发生了非常令人困惑的事情......

这是我看到的……

RevisedProvider 和 obj 是同一个实例。
RevisedProvider = Provider.objects.get(id=obj.id)

然后，将 RevisedProvider 分配给 OldProvider，并在其上调用 save()，这与 obj 的实例相同（2 次保存）。

最后，您删除RevisedProvider.delete()，这是您正在编辑的对象。

当我尝试重现该代码并删除我正在编辑的实例时，django 会抛出 ValidationError。

Sooo，我们需要更多信息来提供帮助。其他的怪事在哪里？

Answer 2

虞姬，

感谢您的提示，感谢您为调查我杂乱无章的编码所做的辛勤工作。

最初我的目标是在公共搜索结果中显示之前必须验证（在管理界面中）的提供者列表。我遇到的问题是，如果 Provider 更新了他们自己的联系信息，我们会自动设置 verify=False（以防发布了不适当的内容）。因此，更新其信息的提供者必须经过重新验证，然后才能出现在数据库中。这很糟糕，因为它们会立即从搜索结果中删除。这就是为什么我对我的数据库进行了修订，以便提供商可以随时编辑和更新他们的信息。现在，在我们手动验证 Provider 信息的更新版本之前，新 更改不会出现。

我想保持联系人的 ID 不变，以便记录历史记录保持不变。这变得太复杂了。所以，刚刚完成它，如果 verified 被检查为 True，它会在 save() 时删除旧版本。

admin.py

​​>

def save_model(self, request, obj, form, change):
    providerid = obj.id
    if Revision.objects.filter(revised_provider=providerid).exists() and obj.revised == True:
        compare = Revision.objects.get(revised_provider=providerid)

        oldproviderid = compare.provider.id
        oldprovider = Provider.objects.get(id=oldproviderid)

        revisedproviderid = compare.revised_provider.id
        revisedprovider = Provider.objects.get(id=revisedproviderid) 


        if change:  #Check to see if we changed anything important
            verified = form.cleaned_data['verified']
            #Means we would have had to manually verified it

            if verified == True: 
            #This means that we have approved to update the old Provider
            #After copying the data over, we destroy what we are saving
                obj.revised = False
                obj.save()
                #If we verfied it, revised = False  

                compare.delete() #Delete Revision 
                oldprovider.delete() #Delete Old Provider

    return super(ProviderAdmin, self).save_model(request, obj, form, change)