python - IntegrityError at/images/create/- NOT NULL 约束失败 : images_image. user_id

Question

我尝试通过其 URL 获取图像并将其保存到数据库，但我收到 IntegrityError at/images/create/- NOT NULL 约束失败:images_image.user_id 抛出给我。以下是可能涉及的文件

models.py

(包含重写 save() 方法的代码，以根据 title 字段的值自动生成 slug 字段)

from django.db import models
from django.conf import settings
from django.utils.text import slugify

class Image(models.Model):
    user = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='images_created')
    title = models.CharField(max_length=200)
    slug = models.SlugField(max_length=200, blank=True)
    url = models.URLField()
    image = models.ImageField(upload_to='images/%Y/%m/%d')
    description = models.TextField(blank=True)
    created = models.DateField(auto_now_add=True, db_index=True)
    users_like = models.ManyToManyField(settings.AUTH_USER_MODEL, 
    related_name='images_liked', blank=True)

    def __str__(self):
        return self.title

    def save(self, *args, **kwargs):
        if not self.slug:
            self.slug = slugify(self.title)
            super(Image, self).save(*args, **kwargs)

forms.py

(包含重写 save() 方法以检索给定图像并保存它的代码)

from urllib import request
from django import forms
from django.core.files.base import ContentFile
from django.utils.text import slugify
from .models import Image

class ImageCreateForm(forms.ModelForm):
    class Meta:
        model = Image
        fields = ('title', 'url', 'description')
        widgets = {
            'url' : forms.HiddenInput,
        }

    def clean_url(self):
        url = self.cleaned_data['url']
        valid_extensions = ['jpg', 'jpeg']
        extension = url.rsplit('.', 1)[1].lower()
        if extension not in valid_extensions:
            raise forms.ValidationError('the given URL doesn\'t match valid image extensions')
        return url

    def save(self, force_insert=False, force_update=False, commit=True):
        image = super(ImageCreateForm, self).save(commit=False)
        image_url = self.cleaned_data['url']
        image_name = '{}.{}'.format(slugify(image.title),
        image_url.rsplit('.', 1)[1].lower())

        # Download image from given URL
        response = request.urlopen(image_url)
        image.image.save(image_name, ContentFile(response.read()))

        if commit:
            image.save()
        return image

views.py

from django.shortcuts import render, redirect
from django.contrib.auth.decorators import login_required
from django.contrib import messages
from .forms import ImageCreateForm

@login_required
def image_create(request):
    if request.method == 'POST':
        # Form is sent
        form = ImageCreateForm(data=request.POST)
        if form.is_valid():
            # Form data is valid
            cd = form.cleaned_data
            new_item = form.save(commit=False)

            # Assign current user to the item
            new_item.user = request.user
            new_item.save()
            messages.success(request, 'Image added successfully')

            # Redirect to the newly created item detail view
            return redirect(new_item.get_absolute_url())
    else:
        # Build form with data provided by the bookmarklet via GET
        form = ImageCreateForm(data=request.GET)

    return render(request, 'images/image/create.html',
    {'section' : 'images', 'form' : form})

怎么了？请有人帮忙

Answer 1

我认为你在表单save方法中遇到麻烦，当你尝试保存图像时，django需要保存实例，所以你有一个错误，我的解决方案是将用户添加到表单数据:

以表格形式

class ImageCreateForm(forms.ModelForm):
    class Meta:
        model = Image
        fields = ('title', 'url', 'description', 'user')
        widgets = {
            'url': forms.HiddenInput,
            'user': forms.HiddenInput,
        }

在 View 中

# Form is sent
data = request.POST.copy()
data.update({'user': request.user.pk })
form = ImageCreateForm(data=data)
if form.is_valid():
    # Form data is valid
    new_item = form.save()
    messages.success(request, 'Image added successfully')
    # Redirect to the newly created item detail view
    return redirect(new_item.get_absolute_url())