django-rest-framework/djangorestframework/tests/parsers.py
2011-05-10 10:49:28 +01:00

130 lines
4.8 KiB
Python

"""
..
>>> from djangorestframework.parsers import FormParser
>>> from djangorestframework.compat import RequestFactory
>>> from djangorestframework.views import BaseView
>>> from StringIO import StringIO
>>> from urllib import urlencode
>>> req = RequestFactory().get('/')
>>> some_view = BaseView()
>>> some_view.request = req # Make as if this request had been dispatched
FormParser
============
Data flatening
----------------
Here is some example data, which would eventually be sent along with a post request :
>>> inpt = urlencode([
... ('key1', 'bla1'),
... ('key2', 'blo1'), ('key2', 'blo2'),
... ])
Default behaviour for :class:`parsers.FormParser`, is to return a single value for each parameter :
>>> FormParser(some_view).parse(StringIO(inpt)) == {'key1': 'bla1', 'key2': 'blo1'}
True
However, you can customize this behaviour by subclassing :class:`parsers.FormParser`, and overriding :meth:`parsers.FormParser.is_a_list` :
>>> class MyFormParser(FormParser):
...
... def is_a_list(self, key, val_list):
... return len(val_list) > 1
This new parser only flattens the lists of parameters that contain a single value.
>>> MyFormParser(some_view).parse(StringIO(inpt)) == {'key1': 'bla1', 'key2': ['blo1', 'blo2']}
True
.. note:: The same functionality is available for :class:`parsers.MultiPartParser`.
Submitting an empty list
--------------------------
When submitting an empty select multiple, like this one ::
<select multiple="multiple" name="key2"></select>
The browsers usually strip the parameter completely. A hack to avoid this, and therefore being able to submit an empty select multiple, is to submit a value that tells the server that the list is empty ::
<select multiple="multiple" name="key2"><option value="_empty"></select>
:class:`parsers.FormParser` provides the server-side implementation for this hack. Considering the following posted data :
>>> inpt = urlencode([
... ('key1', 'blo1'), ('key1', '_empty'),
... ('key2', '_empty'),
... ])
:class:`parsers.FormParser` strips the values ``_empty`` from all the lists.
>>> MyFormParser(some_view).parse(StringIO(inpt)) == {'key1': 'blo1'}
True
Oh ... but wait a second, the parameter ``key2`` isn't even supposed to be a list, so the parser just stripped it.
>>> class MyFormParser(FormParser):
...
... def is_a_list(self, key, val_list):
... return key == 'key2'
...
>>> MyFormParser(some_view).parse(StringIO(inpt)) == {'key1': 'blo1', 'key2': []}
True
Better like that. Note that you can configure something else than ``_empty`` for the empty value by setting :attr:`parsers.FormParser.EMPTY_VALUE`.
"""
import httplib, mimetypes
from tempfile import TemporaryFile
from django.test import TestCase
from djangorestframework.compat import RequestFactory
from djangorestframework.parsers import MultiPartParser
from djangorestframework.views import BaseView
from StringIO import StringIO
def encode_multipart_formdata(fields, files):
"""For testing multipart parser.
fields is a sequence of (name, value) elements for regular form fields.
files is a sequence of (name, filename, value) elements for data to be uploaded as files
Return (content_type, body)."""
BOUNDARY = '----------ThIs_Is_tHe_bouNdaRY_$'
CRLF = '\r\n'
L = []
for (key, value) in fields:
L.append('--' + BOUNDARY)
L.append('Content-Disposition: form-data; name="%s"' % key)
L.append('')
L.append(value)
for (key, filename, value) in files:
L.append('--' + BOUNDARY)
L.append('Content-Disposition: form-data; name="%s"; filename="%s"' % (key, filename))
L.append('Content-Type: %s' % get_content_type(filename))
L.append('')
L.append(value)
L.append('--' + BOUNDARY + '--')
L.append('')
body = CRLF.join(L)
content_type = 'multipart/form-data; boundary=%s' % BOUNDARY
return content_type, body
def get_content_type(filename):
return mimetypes.guess_type(filename)[0] or 'application/octet-stream'
class TestMultiPartParser(TestCase):
def setUp(self):
self.req = RequestFactory()
self.content_type, self.body = encode_multipart_formdata([('key1', 'val1'), ('key1', 'val2')],
[('file1', 'pic.jpg', 'blablabla'), ('file1', 't.txt', 'blobloblo')])
def test_multipartparser(self):
"""Ensure that MultiPartParser can parse multipart/form-data that contains a mix of several files and parameters."""
post_req = RequestFactory().post('/', self.body, content_type=self.content_type)
view = BaseView()
view.request = post_req
parsed = MultiPartParser(view).parse(StringIO(self.body))
self.assertEqual(parsed['key1'], 'val1')
self.assertEqual(parsed.FILES['file1'].read(), 'blablabla')