Django raises MultiValueDictKeyError in File Upload

Question

I have already consulted lots of forums and I can't get an answer. I have installed a file upload in my Django app to save data into my server. But it does not work. Instead, it raises a MultiValueDictKeyError. I guess the problem is that there is not request.FILES (because it raises an error in request.FILES mentions), so the file upload is not working. This is my views.py:

def list_files(request, phase_id):
    phase = get_object_or_404(Phase, pk=int(phase_id))  
    if request.method == 'POST':
    #form = DocumentForm(request.POST, request.FILES)
    form = DocumentForm(request.POST, request.FILES)
    if form.is_valid():
        newdoc = Document(docfile = request.FILES['docfile'], phase = phase_id)
        newdoc.save()
        doc_to_save = request.FILES['docfile']
        filename = doc_to_save._get_name()
        fd = open(settings.MEDIA_URL+'documents/'+str(filename),'wb')
        for chunk in doc_to_save.chunks():
            fd.write(chunk)
        fd.close()

        return HttpResponseRedirect(reverse('list_files')) 
    else:
        form = DocumentForm()

    documents = Document.objects.filter(phase=phase_id)

    return render_to_response('teams_test/list_files.html',{'documents': documents, 'form':form, 'phase':phase}, context_instance = RequestContext(request)
    )

The document form in forms.py:

class DocumentForm(forms.ModelForm):
    docfile = forms.FileField(label='Select a file', help_text='max. 42 megabytes')
    class Meta:
    model = Document

The class document in models.py:

class Document(models.Model):
    docfile = models.FileField(upload_to='documents')
    phase = models.ForeignKey(Phase)

Finally, my html code:

{% extends "layouts/app.html" %}
{% load i18n  user %}

{% block title %}{% trans "Files list" %}{% endblock %}
{% block robots %}noindex,nofollow{% endblock %}


{% block page%}

<div id="page" class="container">
    <div class="header prepend-2 span-20 append-2 last whiteboard">
        <h2 style="margin-left:-40px">{{ phase.name }} files</h2>

        {% if documents %}
        <ul>
        {% for document in documents %}
        <li><a href="{{ document.docfile.url }}">{{ document.docfile.name }}
        {% endfor %}
        </ul>
    {% else %}
        <p>No documents.</p>
    {% endif %}

        <form action="{% url list_files phase.id %}" method="post" enctype="multipart/form-data">
        {% csrf_token %}
        <input id="file" type="file" />
        <input id="submit" type="submit" value="Upload file" />
        </form>
  </div> 
</div>
{% endblock %}

My traceback says:

Exception Type: MultiValueDictKeyError
Exception Value:    "Key 'docfile' not found in <MultiValueDict: {}>"
my_dir/views.py in list_files
    newdoc = Document(docfile = request.FILES['docfile'], phase = phase_id) 

And my QueryDict is empty:

POST:<QueryDict: {u'csrfmiddlewaretoken': [u'UZSwiLaJ78PqSjwSlh3srGReICzTEWY1']}>

Why? What am I doing wrong?

Thanks in advance.

Answer 1

You need to change multipart/form_data to multipart/form-data - that's why request.FILES is empty: the form isn't sending things in the way Django expects due to the typo. [EDIT: this has now been done]

Update 1: Also, rather than directly access request.FILES, try relying on the modelform's default behaviour, as then it'll have been handled as an upload appropriately. ie, newdoc = form.save() should do all you need, from a quick look at it - is there a particular reason you manually saving the file when the modelform can do that for you?

Update 2: Ah, look: you're not assigning a name to your file upload element

From the docs:

HttpRequest.FILES A dictionary-like object containing all uploaded files. Each key in FILES is the name from the <input type="file" name="" />. Each value in FILES is an UploadedFile

So, you need to change

<input id="file" type="file" />

to

or, for default Django convention

<input id="id_docfile" type="file" name="docfile"/>

Indeed, it's usually better to use the Django form to render the actual field, even if you've moved beyond the whole {{form.as_p}} approach:

{{form.docfile}}

PS. if you've not read them fully, I heartily recommend taking the time to go through all of the forms documentation

Answer 2

Modify Post method to

<form action="" method="post" enctype="multipart/form-data">{% csrf_token %}