NOT NULL 约束失败 Django CreateView

Question

我想在这个项目上完成两个目标。首先，我想将登录用户保存为审阅者。其次，我想将外键中的律师值传递到审核表中。（这样，用户可以在律师的详细信息页面上点击评论 link 并评论该律师而不是其他人。）

我一直在第一个目标上，但出现了这个错误。

错误

IntegrityError at /lawyers/karlyn-rosemarie-hylton/review/
NOT NULL constraint failed: lawyers_review.reviewer_id

有人可以解释一下我做错了什么以及如何解决吗？

第二个目标似乎与第一个目标非常相关。我没有收到任何错误。但我想确保我做对了。但是，在我通过第一个错误之前我无法判断。

非常感谢任何帮助摆脱困境的帮助。

models.py

from django.db import models
from django.urls import reverse
from django.template.defaultfilters import slugify
from django.contrib.auth.models import User


class Lawyer(models.Model):
    name = models.CharField(max_length=55,
                            default='')
    picture = models.ImageField(upload_to='media/lawyers/pictures', 
                                default='')
    slug = models.SlugField()

    def average_rating(self):
        all_ratings = map(lambda x: x.rating, self.review_set.all())
        return np.mean(all_ratings)

    def save(self, *args, **kwargs):
        self.slug = (slugify(self.name))
        super(Lawyer, self).save(*args, **kwargs)

    def get_absolute_url(self):
        return reverse('lawyers:detail', kwargs={'slug': self.slug})

    def __str__(self):
        return self.name 


class Review(models.Model):
    RATING_CHOICES = (
        (1, '1'),
        (2, '2'),
        (3, '3'),
        (4, '4'),
        (5, '5'),
    )
    lawyer = models.ForeignKey(Lawyer, 
                                null=True)
    created = models.DateTimeField(auto_now_add=True)
    reviewer = models.ForeignKey(User)
    title = models.CharField(max_length=55,
                                default='')
    comment = models.TextField()
    rating = models.IntegerField(choices=RATING_CHOICES)

    def __str__(self):
        return self.lawyer.name

views.py

from django.shortcuts import render, get_object_or_404
from django.views.generic import (CreateView,
                                    DetailView,
                                    ListView)


from django.contrib.auth.models import User


from .models import Lawyer, Review


class AddLawyerView(CreateView):
    model = Lawyer 
    fields = ['name', 'picture']

    def post_valid(self, form):
        lawyer = form.save(Commit=False)
        lawyer.picture = form.cleaned_data['picture']
        return super(AddLawyerView, self).form_valid(form)


class LawyerDetail(DetailView):
    model = Lawyer 


class LawyerList(ListView):
    model = Lawyer 


class AddReviewView(CreateView):
    model = Review 
    fields = ['rating', 'title', 'comment']

    def post_valid(self, form):
        review = form.save(Commit=False)
        review.lawyer = get_object_or_404(Lawyer, 
                                            slug=self.kwargs.get('slug'))
        review.reviewer = User.objects.get(user=self.request.user)
        return super(AddReview, self).form_valid(form)

urls.py

from django.conf.urls import url


from .views import (AddLawyerView, 
                    LawyerDetail,
                    LawyerList,
                    AddReviewView)


urlpatterns = [
    url(r'^add-lawyer',
        AddLawyerView.as_view(),
        name = 'add-lawyer'),


    url(r'^(?P<slug>[\w-]+)/$',
        LawyerDetail.as_view(),
        name = 'detail'),


    url(r'^$',
        LawyerList.as_view(),
        name = 'list'),


    url(r'^(?P<slug>[\w-]+)/review/$',
        AddReviewView.as_view(),
        name = 'add-review'),
]

根据@Alasdair 和@Sachin Kukreja 的反馈，我回去做了一些更正。我将 "Commit" 更改为 "commit"，将 "post_valid" 更改为 "form_valid"。我还做了一个小调整来简化视图。更正且有效的 AddReviewView 如下所示。有错误的在上面。

谢谢大家！

工作视图：

class AddReviewView(CreateView):
    model = Review 
    fields = ['rating', 'title', 'comment']

    def form_valid(self, form):
        review = form.save(commit=False)
        review.lawyer = get_object_or_404(Lawyer, 
                                            slug=self.kwargs.get('slug'))
        review.reviewer = self.request.user
        return super(AddReviewView, self).form_valid(form)

Answer 1

你那里有一个错字，你正在覆盖 form_valid 但你写的是 post_valid.

def form_valid(self, form):
    review = form.save(Commit=False)
    review.lawyer = get_object_or_404(Lawyer, 
                                        slug=self.kwargs.get('slug'))
    review.reviewer = User.objects.get(user=self.request.user)

    # save and return HttpResponse
    review.save()
    return HttpResponseRedirect(self.get_success_url())

但是，super 调用仍会调用父级 class' form_valid，这仍会引发错误。我想你可以用这个覆盖方法保存评论，return 基础 class return 是什么，即 return HttpResponseRedirect(self.get_success_url())

参考：form_valid in FormMixin class, form_valid in ModelFormMixin class

NOT NULL 约束失败 Django CreateView

NOT NULL constraint failed Django CreateView

python

django

python-3.x

django-class-based-views