python - Django ImportError 无法导入名称请求

Question

我正在使用 Antonio Mele 的 Django-By-Example 一书学习 Django。现在我已经读到第 5 章了，现在我正在尝试创建图像共享应用程序。但是，尽管遵循了该章中的所有说明，但当我尝试在 Django 开发服务器中添加来自外部 URL 的图像时，我还是遇到了 ImportError。

    ImportError at /images/create/

cannot import name request

Request URL:    http://127.0.0.1:8000/images/create/?title=%20Django%20and%20Duke&url=http://upload.wikimedia.org/wikipedia/commons/8/85/Django_Reinhardt_and_Duke_Ellington_(Gottlieb).jpg.
Django Version:     1.8.6
Exception Location:     /home/ciotar/projects/VirtualEnvs/env/bookmarks/bookmarks/images/forms.py in <module>, line 1
Python Version:     2.7.11

我正在使用 Pycharm 并从事件的 virtualenv 实例设置了 python 3.5 解释器。不确定为什么 Django 使用 python 2.7 运行。我想知道这个问题是否会因为 forms.py 和 views.py 模块之间的“request”名称冲突而出现？

/images/urls.py

urlpatterns = [
    url(r'^create/$', views.image_create, name='create'),
]

/images/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):
    """
    View for creating an Image using the JavaScript Bookmarklet.
    """
    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 new 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})

/images/forms.py

from urllib import request
from django.core.files.base import ContentFile
from django.utils.text import slugify
from django import forms
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 does not 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 the given URL
        response = request.urlopen(image_url)
        image.image.save(image_name,
                         ContentFile(response.read()),
                         save=False)

        if commit:
            image.save()
        return image

Answer 1

这是由于 Python 版本的差异。

在 Python 2.7 中，您可能需要替换:

from urllib import request

在你的forms.py中

import urllib2

同样，urllib2 > Request 模块没有 urlopen 方法。所以你将不得不更换行

response = request.urlopen(image_url)

与:

response = urllib2.urlopen(image_url)

在你的forms.py

在这个 SO post 上有一个关于 urllib 和 urllib2 之间的区别的很好的讨论。