我是Python / Django的菜鸟。我继承了别人的应用程序。该应用程序具有此模型：
# -*- encoding: utf8 -*-
from django.db import models
from versatileimagefield.fields import VersatileImageField, PPOIField
class Motion(models.Model):
name = models.CharField(max_length=100)
cover = VersatileImageField(upload_to='motions/capa', ppoi_field='ppoi', null=True)
ppoi = PPOIField()
authors = models.ManyToManyField(Author)
genre = models.ForeignKey(Genre, related_name='motions')
description = models.TextField(verbose_name='Descrição')
@property
def cover_image(self):
if self.cover:
return self.cover.crop['150x150'].url
def __unicode__(self):
return self.name
在django的管理员中，我可以毫无问题地创建此模型的新对象，但是当我尝试浏览此模型的网址（/admin/motion/motion/1/）进行编辑时，我收到了这条消息：
IOError at /admin/motion/motion/1/
cannot identify image file <File: C:\Users\Leda\Projects\TreeOfBooks\media\motions\capa\Infinite_loop_BSOD.jpg>
回溯：
Environment:
Request Method: GET
Request URL: http://doispes:90/admin/motion/motion/1/
Django Version: 1.7.1
Python Version: 2.7.9
Installed Applications:
('grappelli',
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'versatileimagefield',
'tastypie',
'motion',
'loja',
'gerente',
'motiongen')
Installed Middleware:
('django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware')
Template error:
In template C:\Python27\lib\site-packages\grappelli\templates\admin\includes\fieldset.html, error at line 24
cannot identify image file <File: C:\Users\Leda\Projects\TreeOfBooks\media\motions\capa\Infinite_loop_BSOD.jpg>
14 : {% if field.is_checkbox %}
15 : <div class="c-1"> </div>
16 : <div class="c-2">
17 : {{ field.field }}{{ field.label_tag|prettylabel }}
18 : {% else %}
19 : <div class="c-1">{{ field.label_tag|prettylabel }}</div>
20 : <div class="c-2">
21 : {% if field.is_readonly %}
22 : <div class="grp-readonly">{{ field.contents|linebreaksbr }}</div>
23 : {% else %}
24 : {{ field.field }}
25 : {% endif %}
26 : {% endif %}
27 : {% if line.fields|length_is:'1' %}{{ line.errors }}{% endif %}
28 : {% if not line.fields|length_is:'1' and not field.is_readonly %}{{ field.field.errors }}{% endif %}
29 : {% if field.field.help_text %}
30 : <p class="grp-help">{{ field.field.help_text|safe }}</p>
31 : {% endif %}
32 : </div>
33 : </div>
34 : {% endfor %}
Traceback:
File "C:\Python27\lib\site-packages\django\core\handlers\base.py" in get_response
137. response = response.render()
File "C:\Python27\lib\site-packages\django\template\response.py" in render
103. self.content = self.rendered_content
File "C:\Python27\lib\site-packages\django\template\response.py" in rendered_content
80. content = template.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
148. return self._render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in _render
142. return self.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\loader_tags.py" in render
126. return compiled_parent._render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in _render
142. return self.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\loader_tags.py" in render
126. return compiled_parent._render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in _render
142. return self.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\loader_tags.py" in render
65. result = block.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\loader_tags.py" in render
65. result = block.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
201. nodelist.append(node.render(context))
File "C:\Python27\lib\site-packages\django\template\loader_tags.py" in render
150. return template.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
148. return self._render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in _render
142. return self.nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
402. return strip_spaces_between_tags(self.nodelist.render(context).strip())
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
201. nodelist.append(node.render(context))
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
201. nodelist.append(node.render(context))
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
312. return nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\defaulttags.py" in render
312. return nodelist.render(context)
File "C:\Python27\lib\site-packages\django\template\base.py" in render
844. bit = self.render_node(node, context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render_node
80. return node.render(context)
File "C:\Python27\lib\site-packages\django\template\debug.py" in render
93. output = force_text(output)
File "C:\Python27\lib\site-packages\django\utils\encoding.py" in force_text
85. s = six.text_type(s)
File "C:\Python27\lib\site-packages\django\forms\forms.py" in __str__
508. return self.as_widget()
File "C:\Python27\lib\site-packages\django\forms\forms.py" in as_widget
560. return force_text(widget.render(name, self.value(), attrs=attrs))
File "C:\Python27\lib\site-packages\versatileimagefield\widgets.py" in render
198. attrs
File "C:\Python27\lib\site-packages\django\forms\widgets.py" in render
815. output.append(widget.render(name + '_%s' % i, widget_value, final_attrs))
File "C:\Python27\lib\site-packages\versatileimagefield\widgets.py" in render
123. value
File "C:\Python27\lib\site-packages\versatileimagefield\widgets.py" in image_preview
89. 'sized_url': value.thumbnail['300x300'],
File "C:\Python27\lib\site-packages\versatileimagefield\datastructures\sizedimage.py" in __getitem__
111. height=height
File "C:\Python27\lib\site-packages\versatileimagefield\datastructures\sizedimage.py" in create_resized_image
172. path_to_image
File "C:\Python27\lib\site-packages\versatileimagefield\datastructures\base.py" in retrieve_image
124. Image.open(image),
File "C:\Python27\lib\site-packages\PIL\Image.py" in open
2288. % (filename if filename else fp))
Exception Type: IOError at /admin/motion/motion/1/
Exception Value: cannot identify image file <File: C:\Users\Leda\Projects\TreeOfBooks\media\motions\capa\Infinite_loop_BSOD.jpg>
最重要的是，应用程序还使用django-tastypie通过REST api公开模型。当我浏览这个模型的REST URL（/api/v1/estante/?format=json）时，我得到了这个JSON响应：
{
"error_message":"cannot identify image file <File: C:\\Users\\Leda\\Projects\\TreeOfBooks\\media\\motions\\capa\\Infinite_loop_BSOD.jpg>",
"traceback":"Traceback (most recent call last):\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\resources.py\", line 201, in wrapper\n response = callback(request, *args, **kwargs)\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\resources.py\", line 432, in dispatch_list\n return self.dispatch('list', request, **kwargs)\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\resources.py\", line 464, in dispatch\n response = method(request, **kwargs)\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\resources.py\", line 1297, in get_list\n bundles.append(self.full_dehydrate(bundle, for_list=True))\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\resources.py\", line 852, in full_dehydrate\n bundle.data[field_name] = field_object.dehydrate(bundle, for_list=for_list)\n\n File \"C:\\Python27\\lib\\site-packages\\tastypie\\fields.py\", line 116, in dehydrate\n current_object = getattr(current_object, attr, None)\n\n File \"C:\\Users\\Leda\\Projects\\TreeOfBooks\\motion\\models.py\", line 37, in img_capa\n return self.capa.crop['150x150'].url\n\n File \"C:\\Python27\\lib\\site-packages\\versatileimagefield\\datastructures\\sizedimage.py\", line 111, in __getitem__\n height=height\n\n File \"C:\\Python27\\lib\\site-packages\\versatileimagefield\\datastructures\\sizedimage.py\", line 172, in create_resized_image\n path_to_image\n\n File \"C:\\Python27\\lib\\site-packages\\versatileimagefield\\datastructures\\base.py\", line 124, in retrieve_image\n Image.open(image),\n\n File \"C:\\Python27\\lib\\site-packages\\PIL\\Image.py\", line 2288, in open\n % (filename if filename else fp))\n\nIOError: cannot identify image file <File: C:\\Users\\Leda\\Projects\\TreeOfBooks\\media\\motions\\capa\\Infinite_loop_BSOD.jpg>\n"
}
如果我将行return self.capa.crop['150x150'].url更改为return self.capa，则JSON输出将更改为：
{
"meta": {
"limit": 20,
"next": null,
"offset": 0,
"previous": null,
"total_count": 1
},
"objects": [
{
"authors": [
{
"biography": "Meh",
"id": 1,
"name": "Meh",
"resource_uri": ""
}
],
"cover": "/media/motions/capa/Infinite_loop_BSOD.jpg",
"chapters": [
{
"file": "/media/motions/rsz_1rsz_11img_337901552885900.jpg",
"id": 1,
"number": 1,
"resource_uri": "",
"synopsis": ""
},
{
"file": "/media/motions/tumblr_na3jdpPTi71rpu8e5o1_1280.png",
"id": 2,
"number": 2,
"resource_uri": "",
"synopsis": ""
}
],
"description": "Meh",
"datasheet": [
{
"function": "AA",
"id": 1,
"name": "AA",
"resource_uri": "/api/v1/datasheet/1/"
},
{
"function": "BBB",
"id": 2,
"name": "BBB",
"resource_uri": "/api/v1/datasheet/2/"
}
],
"genre": {
"id": 1,
"name": "Cuidado hein",
"resource_uri": "/api/v1/genre/1/"
},
"id": 1,
"cover_image": "motions/capa/Infinite_loop_BSOD.jpg",
"name": "Meh",
"resource_uri": "/api/v1/estante/1/"
}
]
}
但管理员的错误仍将存在。我怎么解决这个问题？我完全迷失了。