自定义django admin model表单提交的例子

如下所示：

希望可以从对admin提交的密码加密，并验证电话号码均为数字。

查看admin.py

from django.contrib import admin
class courseAdmin(admin.ModelAdmin)

我们自定义的管理类，继承与admin.ModelAdmin

查看对应admin模块对应源码

__init__.py

from django.contrib.admin.options import (
HORIZONTAL, VERTICAL, ModelAdmin, StackedInline, TabularInline,FaultyAdmin,
)

从django.contrib.admin.options导入 ModelAdmin

options.py ModelAdmin源码比较长，就不全部列出了，看比较关键的地方

def get_urls(self):
 from django.conf.urls import url

def wrap(view):
  def wrapper(*args, **kwargs):
   return self.admin_site.admin_view(view)(*args, **kwargs)
  wrapper.model_admin = self
  return update_wrapper(wrapper, view)

info = self.model._meta.app_label, self.model._meta.model_name

urlpatterns = [
  url(r'^$', wrap(self.changelist_view), name='％s_％s_changelist' ％ info),
  url(r'^add/$', wrap(self.add_view), name='％s_％s_add' ％ info),
  url(r'^(.+)/history/$', wrap(self.history_view), name='％s_％s_history' ％ info),
  url(r'^(.+)/delete/$', wrap(self.delete_view), name='％s_％s_delete' ％ info),
  url(r'^(.+)/change/$', wrap(self.change_view), name='％s_％s_change' ％ info),
  # For backwards compatibility (was the change url before 1.9)
  url(r'^(.+)/$', wrap(RedirectView.as_view(
   pattern_name='％s:％s_％s_change' ％ ((self.admin_site.name,) + info)
  ))),
 ]
 return urlpatterns

可以看到add操作，交由add_view函数

def add_view(self, request, form_url='', extra_context=None):
 return self.changeform_view(request, None, form_url, extra_context)

@csrf_protect_m
def changeform_view(self, request, object_id=None, form_url='', extra_context=None):
 with transaction.atomic(using=router.db_for_write(self.model)):
  return self._changeform_view(request, object_id, form_url, extra_context)

def _changeform_view(self, request, object_id, form_url, extra_context):
 to_field = request.POST.get(TO_FIELD_VAR, request.GET.get(TO_FIELD_VAR))
 if to_field and not self.to_field_allowed(request, to_field):
  raise DisallowedModelAdminToField("The field ％s cannot be referenced." ％ to_field)

model = self.model
 opts = model._meta

if request.method == 'POST' and '_saveasnew' in request.POST:
  object_id = None

add = object_id is None

if add:
  if not self.has_add_permission(request):
   raise PermissionDenied
  obj = None

else:
  obj = self.get_object(request, unquote(object_id), to_field)

if not self.has_change_permission(request, obj):
   raise PermissionDenied

if obj is None:
   return self._get_obj_does_not_exist_redirect(request, opts, object_id)

ModelForm = self.get_form(request, obj)
 if request.method == 'POST':
  form = ModelForm(request.POST, request.FILES, instance=obj)
  if form.is_valid():
   form_validated = True
   new_object = self.save_form(request, form, change=not add)
  else:
   form_validated = False
   new_object = form.instance
  formsets, inline_instances = self._create_formsets(request, new_object, change=not add)
  if all_valid(formsets) and form_validated:
   self.save_model(request, new_object, form, not add)
   self.save_related(request, form, formsets, not add)
   change_message = self.construct_change_message(request, form, formsets, add)
   if add:
    self.log_addition(request, new_object, change_message)
    return self.response_add(request, new_object)
   else:
    self.log_change(request, new_object, change_message)
    return self.response_change(request, new_object)
  else:
   form_validated = False
 else:
  if add:
   initial = self.get_changeform_initial_data(request)
   form = ModelForm(initial=initial)
   formsets, inline_instances = self._create_formsets(request, form.instance, change=False)
  else:
   form = ModelForm(instance=obj)
   formsets, inline_instances = self._create_formsets(request, obj, change=True)

adminForm = helpers.AdminForm(
  form,
  list(self.get_fieldsets(request, obj)),
  self.get_prepopulated_fields(request, obj),
  self.get_readonly_fields(request, obj),
  model_admin=self)
 media = self.media + adminForm.media

inline_formsets = self.get_inline_formsets(request, formsets, inline_instances, obj)
 for inline_formset in inline_formsets:
  media = media + inline_formset.media

context = dict(
  self.admin_site.each_context(request),
  title=(_('Add ％s') if add else _('Change ％s')) ％ force_text(opts.verbose_name),
  adminform=adminForm,
  object_id=object_id,
  original=obj,
  is_popup=(IS_POPUP_VAR in request.POST or
     IS_POPUP_VAR in request.GET),
  to_field=to_field,
  media=media,
  inline_admin_formsets=inline_formsets,
  errors=helpers.AdminErrorList(form, formsets),
  preserved_filters=self.get_preserved_filters(request),
 )

# Hide the "Save" and "Save and continue" buttons if "Save as New" was
 # previously chosen to prevent the interface from getting confusing.
 if request.method == 'POST' and not form_validated and "_saveasnew" in request.POST:
  context['show_save'] = False
  context['show_save_and_continue'] = False
  # Use the change template instead of the add template.
  add = False

context.update(extra_context or {})

form = ModelForm(request.POST, request.FILES, instance=obj)

这里找到form表单的内容

form.is_valid()

验证表单内容是否合法，查看这个函数

首先找到ModelForm类

在

django\forms\models.py

class ModelForm(six.with_metaclass(ModelFormMetaclass, BaseModelForm)):
pass

查看BaseModelForm

class BaseModelForm(BaseForm):

django\forms\forms.py
class BaseForm(object):
def is_valid(self):
 """
 Returns True if the form has no errors. Otherwise, False. If errors are
 being ignored, returns False.
 """

return self.is_bound and not self.errors
 @property
def errors(self):
 "Returns an ErrorDict for the data provided for the form"
 if self._errors is None:
  self.full_clean()
 return self._errors

def full_clean(self):
 """
 Cleans all of self.data and populates self._errors and
 self.cleaned_data.
 """
 self._errors = ErrorDict()
 if not self.is_bound: # Stop further processing.
  return
 self.cleaned_data = {}
 # If the form is permitted to be empty, and none of the form data has
 # changed from the initial data, short circuit any validation.
 if self.empty_permitted and not self.has_changed():
  return

self._clean_fields()
 self._clean_form()
 self._post_clean()
def _clean_fields(self):
 for name, field in self.fields.items():
  # value_from_datadict() gets the data from the data dictionaries.
  # Each widget type knows how to retrieve its own data, because some
  # widgets split data over several HTML fields.
  #print(type(name))
  print(name,field)
  if field.disabled:
   value = self.get_initial_for_field(field, name)
  else:
   value = field.widget.value_from_datadict(self.data, self.files, self.add_prefix(name))
  try:
   if isinstance(field, FileField):
    initial = self.get_initial_for_field(field, name)
    value = field.clean(value, initial)
   else:
    value = field.clean(value)
   self.cleaned_data[name] = value
   if hasattr(self, 'clean_％s' ％ name):
    value = getattr(self, 'clean_％s' ％ name)()
    self.cleaned_data[name] = value
  except ValidationError as e:
   #print(e)
   self.add_error(name, e)

上面列出函数在表单验证的过程中，顺序调用，可以看到添加错误的主要函数为_clean_fields，虽然没有继续仔细查看，但感觉关键在于field.clean(value)，对应的field在我们声明对应model类时会保存相应字段的信息，这里做检查，如果不符合，则raise ValidationError，符合的haul就把新的数据放入到表单的cleaned_data中。

这一段来自官网的教程，这里指出错误信息的关键字包括，null, blank, invalid, invalid_choice, unique, and unique_for_date。刚才的clean函数应该就是检查这些地方。

The error_messages argument lets you override the default messages that the field will raise. Pass in a dictionary with keys matching the error messages you want to override. Error message keys include null, blank, invalid, invalid_choice, unique, and unique_for_date. Additional error message keys are specified for each field in the Field types section below.

到了这一部，基本已经可以达到目的了，我们可以看到 self.add_error函数。

然后回到options.py的ModelAdmin,我们可以写一个类继承ModelAdmin，然后重写新类的_changeform_view函数，避免对其它部分造成影响。

重写部分如下：

if form.is_valid():
   form_validated = True
   if not re.match('\d+',form.data['tel']):
    form_validated=False
    form.add_error('tel','电话号码必须为纯数字')
   if not re.match('\d+',form.data['number']):
    form_validated=False
    form.add_error('number','学工号必须为纯数字')
   if not form_validated:
    new_object=form.instance
   else:
    passw=form.data['password']
    m=md5()
    m.update(passw.encode('utf-8'))
    form.data['password']=m.hexdigest()
    new_object = self.save_form(request, form, change=not add)

来源：https://blog.csdn.net/zslngu/article/details/80560496