django-fsm:权限不引发异常

Question

我在 django-fsm 中让基于源和目标规则的转换装饰器运行良好(有限状态机)。现在我正在尝试添加权限处理。这看起来很简单，但似乎无论我做什么，转换都会执行，无论用户是否拥有权限。我试过 Django 权限字符串，我试过 lambda ，根据文档。我已经尝试了所有这些:

@transition(field=state, source='prog', target='appr', permission='claims.change_claim')

和

@transition(field=state, source='prog', target='appr', permission=lambda instance, user: not user.has_perm('claims.change_claim'),)

并且，就像仔细检查，因为 permission应该响应任何返回 True/False 的可调用对象，简单地:

@transition(field=state, source='prog', target='appr', permission=False)
def approve(self):

这应该引发 TransitionNotAllowed访问过渡时的所有用户。但是不 - 即使没有权限的基本用户仍然可以执行转换( claim.approve() )。

为了证明我的权限字符串是正确的:

print(has_transition_perm(claim.approve, request.user))

打印 False。我正在按如下方式进行验证(适用于源/目标):

class ClaimEditForm(forms.ModelForm):
    '''
    Some users can transition claims through allowable states
    '''

    def clean_state(self):
        state = self.cleaned_data['state']
        if state == 'appr':
            try:
                self.instance.approve()
            except TransitionNotAllowed:
                raise forms.ValidationError("Claim could not be approved")
        return state

    class Meta:
        model = Claim
        fields = (
            'state',
        )

View 处理程序是标准的:

if request.method == "POST":
    claim_edit_form = ClaimEditForm(request.POST, instance=claim)
    if claim_edit_form.is_valid():  # Validate transition rules

我错过了什么？谢谢。

Answer 1

问题原来是permission属性执行与源/目标验证器不同的验证。您必须评估在代码中其他地方的装饰器中建立的权限，而不是装饰器引发错误。因此，要从表单执行权限验证，您需要传入用户对象，在表单的 init 中接收用户。 ，然后与 has_transition_perm 的结果进行比较.所以这有效:

# model
@transition(field=state, source='prog', target='appr', permission='claims.change_claim')
def approve(self):
....

# view
if request.method == "POST":
    claim_edit_form = ClaimEditForm(request.user, request.POST, instance=claim)
        ....

# form
from django_fsm import has_transition_perm

class ClaimEditForm(forms.ModelForm):
    '''
    Some users can transition claims through allowable states
    (see permission property on claim.approve() decorator)
    '''

    def __init__(self, user, *args, **kwargs):
        # We need to pass the user into the form to validate permissions
        self.user = user
        super(ClaimEditForm, self).__init__(*args, **kwargs)

    def clean_state(self):
        state = self.cleaned_data['state']
        if state == 'appr':
            if not has_transition_perm(self.instance.approve, self.user):
                raise forms.ValidationError("You do not have permission for this transition")