Django复用UserCreationForm更新用户时避免重复生成随机密码

解决方案 #

核心逻辑：Django 的 ModelForm 可通过 self.instance.pk 判断当前操作是创建新用户还是更新已有用户，仅在创建新用户时执行密码生成逻辑即可。

修改后的表单代码

class EmployeeRegistrationForm(UserCreationForm):
    email = forms.EmailField(required=True, widget=forms.EmailInput(attrs={'class': 'form-control mb-2',
                                                                           'placeholder': 'Email address'}))
    first_name = forms.CharField(widget=forms.TextInput(attrs={'class': 'form-control mb-2',
                                                               'placeholder': 'First name'}))
    last_name = forms.CharField(
        widget=forms.TextInput(attrs={'class': 'form-control mb-2', 'placeholder': 'Last name'}))

    password1 = None
    password2 = None

    class Meta:
        model = User
        fields = ['email', 'first_name', 'last_name']

    def clean(self):
        cleaned_data = super().clean()
        # 仅新用户生成随机密码
        if not self.instance.pk:
            password = User.objects.make_random_password(length=10,
                                                     allowed_chars='abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789')
            cleaned_data['password1'] = password
            cleaned_data['password2'] = password
        return cleaned_data

    def save(self, commit=True):
        user = super().save(commit=False)

        user.email = self.cleaned_data['email']
        user.first_name = self.cleaned_data['first_name']
        user.last_name = self.cleaned_data['last_name']
        if user.username == '':
            if len(user.first_name.split()) and len(user.last_name.split()) > 1:
                username = f'{"".join(user.first_name.split()[:2])}{"."}{"".join(user.last_name.split())}'
            elif len(user.first_name.split()) > 1:
                username = f'{"".join(user.first_name.split()[:2])}{"."}{user.last_name}'
            elif len(user.last_name.split()) > 1:
                username = f'{user.first_name}{"."}{"".join(user.last_name.split())}'
            else:
                username = f'{user.first_name}{"."}{user.last_name}'
            username = username.lower()
            user.username = username
        
        # 仅新用户设置密码
        if not self.instance.pk:
            user.set_password(self.cleaned_data['password1'])

        if commit:
            user.save()
        return user

修改完成后原视图无需调整，编辑用户资料时将不再自动生成新密码，仅保留用户名、姓名、邮箱等字段的更新能力。

内容的提问来源于stack exchange，提问作者John Todorovic