So as I understand your problem is not how to generate dynamically this file, but creating a link for people to download it...
What I suggest is the following:
0) Create a model for your file, if you want to generate it dynamically don't use the FileField, but just the info you need for generating this file:
class ZipStored(models.Model):
zip = FileField(upload_to="/choose/a/path/")
1) Create and store your Zip. This step is important, you create your zip in memory, and then cast it to assign it to the FileField:
function create_my_zip(request, [...]):
[...]
# This is a in-memory file
file_like = StringIO.StringIO()
# Create your zip, do all your stuff
zf = zipfile.ZipFile(file_like, mode='w')
[...]
# Your zip is saved in this "file"
zf.close()
file_like.seek(0)
# To store it we can use a InMemoryUploadedFile
inMemory = InMemoryUploadedFile(file_like, None, "my_zip_%s" % filename, 'application/zip', file_like.len, None)
zip = ZipStored(zip=inMemory)
# Your zip will be stored!
zip.save()
# Notify the user the zip was created or whatever
[...]
2) Create a url, for example get a number matching the id, you can also use a slugfield (this)
url(r'^get_my_zip/(\d+)$', "zippyApp.views.get_zip")
3) Now the view, this view will return the file matching the id passed in the url, you can also use a slug sending the text instead of the id, and make the get filtering by your slugfield.
function get_zip(request, id):
myzip = ZipStored.object.get(pk = id)
filename = myzip.zip.name.split('/')[-1]
# You got the zip! Now, return it!
response = HttpResponse(myzip.file, content_type='application/zip')
response['Content-Disposition'] = 'attachment; filename=%s' % filename