django/tests/httpwrappers/tests.py

import copy
import json
import os
import pickle
import unittest
import uuid

from django.core.exceptions import DisallowedRedirect
from django.core.serializers.json import DjangoJSONEncoder
from django.core.signals import request_finished
from django.db import close_old_connections
from django.http import (
    BadHeaderError, HttpResponse, HttpResponseNotAllowed,
    HttpResponseNotModified, HttpResponsePermanentRedirect,
    HttpResponseRedirect, JsonResponse, QueryDict, SimpleCookie,
    StreamingHttpResponse, parse_cookie,
)
from django.test import SimpleTestCase
from django.utils.functional import lazystr


class QueryDictTests(SimpleTestCase):
    def test_create_with_no_args(self):
        self.assertEqual(QueryDict(), QueryDict(''))

    def test_missing_key(self):
        q = QueryDict()
        with self.assertRaises(KeyError):
            q.__getitem__('foo')

    def test_immutability(self):
        q = QueryDict()
        with self.assertRaises(AttributeError):
            q.__setitem__('something', 'bar')
        with self.assertRaises(AttributeError):
            q.setlist('foo', ['bar'])
        with self.assertRaises(AttributeError):
            q.appendlist('foo', ['bar'])
        with self.assertRaises(AttributeError):
            q.update({'foo': 'bar'})
        with self.assertRaises(AttributeError):
            q.pop('foo')
        with self.assertRaises(AttributeError):
            q.popitem()
        with self.assertRaises(AttributeError):
            q.clear()

    def test_immutable_get_with_default(self):
        q = QueryDict()
        self.assertEqual(q.get('foo', 'default'), 'default')

    def test_immutable_basic_operations(self):
        q = QueryDict()
        self.assertEqual(q.getlist('foo'), [])
        self.assertNotIn('foo', q)
        self.assertEqual(list(q), [])
        self.assertEqual(list(q.items()), [])
        self.assertEqual(list(q.lists()), [])
        self.assertEqual(list(q.keys()), [])
        self.assertEqual(list(q.values()), [])
        self.assertEqual(len(q), 0)
        self.assertEqual(q.urlencode(), '')

    def test_single_key_value(self):
        """Test QueryDict with one key/value pair"""

        q = QueryDict('foo=bar')
        self.assertEqual(q['foo'], 'bar')
        with self.assertRaises(KeyError):
            q.__getitem__('bar')
        with self.assertRaises(AttributeError):
            q.__setitem__('something', 'bar')

        self.assertEqual(q.get('foo', 'default'), 'bar')
        self.assertEqual(q.get('bar', 'default'), 'default')
        self.assertEqual(q.getlist('foo'), ['bar'])
        self.assertEqual(q.getlist('bar'), [])

        with self.assertRaises(AttributeError):
            q.setlist('foo', ['bar'])
        with self.assertRaises(AttributeError):
            q.appendlist('foo', ['bar'])

        self.assertIn('foo', q)
        self.assertNotIn('bar', q)

        self.assertEqual(list(q), ['foo'])
        self.assertEqual(list(q.items()), [('foo', 'bar')])
        self.assertEqual(list(q.lists()), [('foo', ['bar'])])
        self.assertEqual(list(q.keys()), ['foo'])
        self.assertEqual(list(q.values()), ['bar'])
        self.assertEqual(len(q), 1)

        with self.assertRaises(AttributeError):
            q.update({'foo': 'bar'})
        with self.assertRaises(AttributeError):
            q.pop('foo')
        with self.assertRaises(AttributeError):
            q.popitem()
        with self.assertRaises(AttributeError):
            q.clear()
        with self.assertRaises(AttributeError):
            q.setdefault('foo', 'bar')

        self.assertEqual(q.urlencode(), 'foo=bar')

    def test_urlencode(self):
        q = QueryDict(mutable=True)
        q['next'] = '/a&b/'
        self.assertEqual(q.urlencode(), 'next=%2Fa%26b%2F')
        self.assertEqual(q.urlencode(safe='/'), 'next=/a%26b/')
        q = QueryDict(mutable=True)
        q['next'] = '/t\xebst&key/'
        self.assertEqual(q.urlencode(), 'next=%2Ft%C3%ABst%26key%2F')
        self.assertEqual(q.urlencode(safe='/'), 'next=/t%C3%ABst%26key/')

    def test_urlencode_int(self):
        # Normally QueryDict doesn't contain non-string values but lazily
        # written tests may make that mistake.
        q = QueryDict(mutable=True)
        q['a'] = 1
        self.assertEqual(q.urlencode(), 'a=1')

    def test_mutable_copy(self):
        """A copy of a QueryDict is mutable."""
        q = QueryDict().copy()
        with self.assertRaises(KeyError):
            q.__getitem__("foo")
        q['name'] = 'john'
        self.assertEqual(q['name'], 'john')

    def test_mutable_delete(self):
        q = QueryDict(mutable=True)
        q['name'] = 'john'
        del q['name']
        self.assertNotIn('name', q)

    def test_basic_mutable_operations(self):
        q = QueryDict(mutable=True)
        q['name'] = 'john'
        self.assertEqual(q.get('foo', 'default'), 'default')
        self.assertEqual(q.get('name', 'default'), 'john')
        self.assertEqual(q.getlist('name'), ['john'])
        self.assertEqual(q.getlist('foo'), [])

        q.setlist('foo', ['bar', 'baz'])
        self.assertEqual(q.get('foo', 'default'), 'baz')
        self.assertEqual(q.getlist('foo'), ['bar', 'baz'])

        q.appendlist('foo', 'another')
        self.assertEqual(q.getlist('foo'), ['bar', 'baz', 'another'])
        self.assertEqual(q['foo'], 'another')
        self.assertIn('foo', q)

        self.assertCountEqual(q, ['foo', 'name'])
        self.assertCountEqual(q.items(), [('foo', 'another'), ('name', 'john')])
        self.assertCountEqual(q.lists(), [('foo', ['bar', 'baz', 'another']), ('name', ['john'])])
        self.assertCountEqual(q.keys(), ['foo', 'name'])
        self.assertCountEqual(q.values(), ['another', 'john'])

        q.update({'foo': 'hello'})
        self.assertEqual(q['foo'], 'hello')
        self.assertEqual(q.get('foo', 'not available'), 'hello')
        self.assertEqual(q.getlist('foo'), ['bar', 'baz', 'another', 'hello'])
        self.assertEqual(q.pop('foo'), ['bar', 'baz', 'another', 'hello'])
        self.assertEqual(q.pop('foo', 'not there'), 'not there')
        self.assertEqual(q.get('foo', 'not there'), 'not there')
        self.assertEqual(q.setdefault('foo', 'bar'), 'bar')
        self.assertEqual(q['foo'], 'bar')
        self.assertEqual(q.getlist('foo'), ['bar'])
        self.assertIn(q.urlencode(), ['foo=bar&name=john', 'name=john&foo=bar'])

        q.clear()
        self.assertEqual(len(q), 0)

    def test_multiple_keys(self):
        """Test QueryDict with two key/value pairs with same keys."""

        q = QueryDict('vote=yes&vote=no')

        self.assertEqual(q['vote'], 'no')
        with self.assertRaises(AttributeError):
            q.__setitem__('something', 'bar')

        self.assertEqual(q.get('vote', 'default'), 'no')
        self.assertEqual(q.get('foo', 'default'), 'default')
        self.assertEqual(q.getlist('vote'), ['yes', 'no'])
        self.assertEqual(q.getlist('foo'), [])

        with self.assertRaises(AttributeError):
            q.setlist('foo', ['bar', 'baz'])
        with self.assertRaises(AttributeError):
            q.setlist('foo', ['bar', 'baz'])
        with self.assertRaises(AttributeError):
            q.appendlist('foo', ['bar'])

        self.assertIn('vote', q)
        self.assertNotIn('foo', q)
        self.assertEqual(list(q), ['vote'])
        self.assertEqual(list(q.items()), [('vote', 'no')])
        self.assertEqual(list(q.lists()), [('vote', ['yes', 'no'])])
        self.assertEqual(list(q.keys()), ['vote'])
        self.assertEqual(list(q.values()), ['no'])
        self.assertEqual(len(q), 1)

        with self.assertRaises(AttributeError):
            q.update({'foo': 'bar'})
        with self.assertRaises(AttributeError):
            q.pop('foo')
        with self.assertRaises(AttributeError):
            q.popitem()
        with self.assertRaises(AttributeError):
            q.clear()
        with self.assertRaises(AttributeError):
            q.setdefault('foo', 'bar')
        with self.assertRaises(AttributeError):
            q.__delitem__('vote')

    def test_pickle(self):
        q = QueryDict()
        q1 = pickle.loads(pickle.dumps(q, 2))
        self.assertEqual(q, q1)
        q = QueryDict('a=b&c=d')
        q1 = pickle.loads(pickle.dumps(q, 2))
        self.assertEqual(q, q1)
        q = QueryDict('a=b&c=d&a=1')
        q1 = pickle.loads(pickle.dumps(q, 2))
        self.assertEqual(q, q1)

    def test_update_from_querydict(self):
        """Regression test for #8278: QueryDict.update(QueryDict)"""
        x = QueryDict("a=1&a=2", mutable=True)
        y = QueryDict("a=3&a=4")
        x.update(y)
        self.assertEqual(x.getlist('a'), ['1', '2', '3', '4'])

    def test_non_default_encoding(self):
        """#13572 - QueryDict with a non-default encoding"""
        q = QueryDict('cur=%A4', encoding='iso-8859-15')
        self.assertEqual(q.encoding, 'iso-8859-15')
        self.assertEqual(list(q.items()), [('cur', '€')])
        self.assertEqual(q.urlencode(), 'cur=%A4')
        q = q.copy()
        self.assertEqual(q.encoding, 'iso-8859-15')
        self.assertEqual(list(q.items()), [('cur', '€')])
        self.assertEqual(q.urlencode(), 'cur=%A4')
        self.assertEqual(copy.copy(q).encoding, 'iso-8859-15')
        self.assertEqual(copy.deepcopy(q).encoding, 'iso-8859-15')

    def test_querydict_fromkeys(self):
        self.assertEqual(QueryDict.fromkeys(['key1', 'key2', 'key3']), QueryDict('key1&key2&key3'))

    def test_fromkeys_with_nonempty_value(self):
        self.assertEqual(
            QueryDict.fromkeys(['key1', 'key2', 'key3'], value='val'),
            QueryDict('key1=val&key2=val&key3=val')
        )

    def test_fromkeys_is_immutable_by_default(self):
        # Match behavior of __init__() which is also immutable by default.
        q = QueryDict.fromkeys(['key1', 'key2', 'key3'])
        with self.assertRaisesMessage(AttributeError, 'This QueryDict instance is immutable'):
            q['key4'] = 'nope'

    def test_fromkeys_mutable_override(self):
        q = QueryDict.fromkeys(['key1', 'key2', 'key3'], mutable=True)
        q['key4'] = 'yep'
        self.assertEqual(q, QueryDict('key1&key2&key3&key4=yep'))

    def test_duplicates_in_fromkeys_iterable(self):
        self.assertEqual(QueryDict.fromkeys('xyzzy'), QueryDict('x&y&z&z&y'))

    def test_fromkeys_with_nondefault_encoding(self):
        key_utf16 = b'\xff\xfe\x8e\x02\xdd\x01\x9e\x02'
        value_utf16 = b'\xff\xfe\xdd\x01n\x00l\x00P\x02\x8c\x02'
        q = QueryDict.fromkeys([key_utf16], value=value_utf16, encoding='utf-16')
        expected = QueryDict('', mutable=True)
        expected['ʎǝʞ'] = 'ǝnlɐʌ'
        self.assertEqual(q, expected)

    def test_fromkeys_empty_iterable(self):
        self.assertEqual(QueryDict.fromkeys([]), QueryDict(''))

    def test_fromkeys_noniterable(self):
        with self.assertRaises(TypeError):
            QueryDict.fromkeys(0)


class HttpResponseTests(SimpleTestCase):

    def test_headers_type(self):
        r = HttpResponse()

        # ASCII strings or bytes values are converted to strings.
        r.headers['key'] = 'test'
        self.assertEqual(r.headers['key'], 'test')
        r.headers['key'] = b'test'
        self.assertEqual(r.headers['key'], 'test')
        self.assertIn(b'test', r.serialize_headers())

        # Non-ASCII values are serialized to Latin-1.
        r.headers['key'] = 'café'
        self.assertIn('café'.encode('latin-1'), r.serialize_headers())

        # Other Unicode values are MIME-encoded (there's no way to pass them as
        # bytes).
        r.headers['key'] = '†'
        self.assertEqual(r.headers['key'], '=?utf-8?b?4oCg?=')
        self.assertIn(b'=?utf-8?b?4oCg?=', r.serialize_headers())

        # The response also converts string or bytes keys to strings, but requires
        # them to contain ASCII
        r = HttpResponse()
        del r.headers['Content-Type']
        r.headers['foo'] = 'bar'
        headers = list(r.headers.items())
        self.assertEqual(len(headers), 1)
        self.assertEqual(headers[0], ('foo', 'bar'))

        r = HttpResponse()
        del r.headers['Content-Type']
        r.headers[b'foo'] = 'bar'
        headers = list(r.headers.items())
        self.assertEqual(len(headers), 1)
        self.assertEqual(headers[0], ('foo', 'bar'))
        self.assertIsInstance(headers[0][0], str)

        r = HttpResponse()
        with self.assertRaises(UnicodeError):
            r.headers.__setitem__('føø', 'bar')
        with self.assertRaises(UnicodeError):
            r.headers.__setitem__('føø'.encode(), 'bar')

    def test_long_line(self):
        # Bug #20889: long lines trigger newlines to be added to headers
        # (which is not allowed due to bug #10188)
        h = HttpResponse()
        f = b'zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz a\xcc\x88'
        f = f.decode('utf-8')
        h.headers['Content-Disposition'] = 'attachment; filename="%s"' % f
        # This one is triggering https://bugs.python.org/issue20747, that is Python
        # will itself insert a newline in the header
        h.headers['Content-Disposition'] = 'attachment; filename="EdelRot_Blu\u0308te (3)-0.JPG"'

    def test_newlines_in_headers(self):
        # Bug #10188: Do not allow newlines in headers (CR or LF)
        r = HttpResponse()
        with self.assertRaises(BadHeaderError):
            r.headers.__setitem__('test\rstr', 'test')
        with self.assertRaises(BadHeaderError):
            r.headers.__setitem__('test\nstr', 'test')

    def test_dict_behavior(self):
        """
        Test for bug #14020: Make HttpResponse.get work like dict.get
        """
        r = HttpResponse()
        self.assertIsNone(r.get('test'))

    def test_non_string_content(self):
        # Bug 16494: HttpResponse should behave consistently with non-strings
        r = HttpResponse(12345)
        self.assertEqual(r.content, b'12345')

        # test content via property
        r = HttpResponse()
        r.content = 12345
        self.assertEqual(r.content, b'12345')

    def test_memoryview_content(self):
        r = HttpResponse(memoryview(b'memoryview'))
        self.assertEqual(r.content, b'memoryview')

    def test_iter_content(self):
        r = HttpResponse(['abc', 'def', 'ghi'])
        self.assertEqual(r.content, b'abcdefghi')

        # test iter content via property
        r = HttpResponse()
        r.content = ['idan', 'alex', 'jacob']
        self.assertEqual(r.content, b'idanalexjacob')

        r = HttpResponse()
        r.content = [1, 2, 3]
        self.assertEqual(r.content, b'123')

        # test odd inputs
        r = HttpResponse()
        r.content = ['1', '2', 3, '\u079e']
        # '\xde\x9e' == unichr(1950).encode()
        self.assertEqual(r.content, b'123\xde\x9e')

        # .content can safely be accessed multiple times.
        r = HttpResponse(iter(['hello', 'world']))
        self.assertEqual(r.content, r.content)
        self.assertEqual(r.content, b'helloworld')
        # __iter__ can safely be called multiple times (#20187).
        self.assertEqual(b''.join(r), b'helloworld')
        self.assertEqual(b''.join(r), b'helloworld')
        # Accessing .content still works.
        self.assertEqual(r.content, b'helloworld')

        # Accessing .content also works if the response was iterated first.
        r = HttpResponse(iter(['hello', 'world']))
        self.assertEqual(b''.join(r), b'helloworld')
        self.assertEqual(r.content, b'helloworld')

        # Additional content can be written to the response.
        r = HttpResponse(iter(['hello', 'world']))
        self.assertEqual(r.content, b'helloworld')
        r.write('!')
        self.assertEqual(r.content, b'helloworld!')

    def test_iterator_isnt_rewound(self):
        # Regression test for #13222
        r = HttpResponse('abc')
        i = iter(r)
        self.assertEqual(list(i), [b'abc'])
        self.assertEqual(list(i), [])

    def test_lazy_content(self):
        r = HttpResponse(lazystr('helloworld'))
        self.assertEqual(r.content, b'helloworld')

    def test_file_interface(self):
        r = HttpResponse()
        r.write(b"hello")
        self.assertEqual(r.tell(), 5)
        r.write("привет")
        self.assertEqual(r.tell(), 17)

        r = HttpResponse(['abc'])
        r.write('def')
        self.assertEqual(r.tell(), 6)
        self.assertEqual(r.content, b'abcdef')

        # with Content-Encoding header
        r = HttpResponse()
        r.headers['Content-Encoding'] = 'winning'
        r.write(b'abc')
        r.write(b'def')
        self.assertEqual(r.content, b'abcdef')

    def test_stream_interface(self):
        r = HttpResponse('asdf')
        self.assertEqual(r.getvalue(), b'asdf')

        r = HttpResponse()
        self.assertIs(r.writable(), True)
        r.writelines(['foo\n', 'bar\n', 'baz\n'])
        self.assertEqual(r.content, b'foo\nbar\nbaz\n')

    def test_unsafe_redirect(self):
        bad_urls = [
            'data:text/html,<script>window.alert("xss")</script>',
            'mailto:test@example.com',
            'file:///etc/passwd',
        ]
        for url in bad_urls:
            with self.assertRaises(DisallowedRedirect):
                HttpResponseRedirect(url)
            with self.assertRaises(DisallowedRedirect):
                HttpResponsePermanentRedirect(url)

    def test_header_deletion(self):
        r = HttpResponse('hello')
        r.headers['X-Foo'] = 'foo'
        del r.headers['X-Foo']
        self.assertNotIn('X-Foo', r.headers)
        # del doesn't raise a KeyError on nonexistent headers.
        del r.headers['X-Foo']

    def test_instantiate_with_headers(self):
        r = HttpResponse('hello', headers={'X-Foo': 'foo'})
        self.assertEqual(r.headers['X-Foo'], 'foo')
        self.assertEqual(r.headers['x-foo'], 'foo')

    def test_content_type(self):
        r = HttpResponse('hello', content_type='application/json')
        self.assertEqual(r.headers['Content-Type'], 'application/json')

    def test_content_type_headers(self):
        r = HttpResponse('hello', headers={'Content-Type': 'application/json'})
        self.assertEqual(r.headers['Content-Type'], 'application/json')

    def test_content_type_mutually_exclusive(self):
        msg = (
            "'headers' must not contain 'Content-Type' when the "
            "'content_type' parameter is provided."
        )
        with self.assertRaisesMessage(ValueError, msg):
            HttpResponse(
                'hello',
                content_type='application/json',
                headers={'Content-Type': 'text/csv'},
            )


class HttpResponseSubclassesTests(SimpleTestCase):
    def test_redirect(self):
        response = HttpResponseRedirect('/redirected/')
        self.assertEqual(response.status_code, 302)
        # Standard HttpResponse init args can be used
        response = HttpResponseRedirect(
            '/redirected/',
            content='The resource has temporarily moved',
            content_type='text/html',
        )
        self.assertContains(response, 'The resource has temporarily moved', status_code=302)
        self.assertEqual(response.url, response.headers['Location'])

    def test_redirect_lazy(self):
        """Make sure HttpResponseRedirect works with lazy strings."""
        r = HttpResponseRedirect(lazystr('/redirected/'))
        self.assertEqual(r.url, '/redirected/')

    def test_redirect_repr(self):
        response = HttpResponseRedirect('/redirected/')
        expected = '<HttpResponseRedirect status_code=302, "text/html; charset=utf-8", url="/redirected/">'
        self.assertEqual(repr(response), expected)

    def test_invalid_redirect_repr(self):
        """
        If HttpResponseRedirect raises DisallowedRedirect, its __repr__()
        should work (in the debug view, for example).
        """
        response = HttpResponseRedirect.__new__(HttpResponseRedirect)
        with self.assertRaisesMessage(DisallowedRedirect, "Unsafe redirect to URL with protocol 'ssh'"):
            HttpResponseRedirect.__init__(response, 'ssh://foo')
        expected = '<HttpResponseRedirect status_code=302, "text/html; charset=utf-8", url="ssh://foo">'
        self.assertEqual(repr(response), expected)

    def test_not_modified(self):
        response = HttpResponseNotModified()
        self.assertEqual(response.status_code, 304)
        # 304 responses should not have content/content-type
        with self.assertRaises(AttributeError):
            response.content = "Hello dear"
        self.assertNotIn('content-type', response)

    def test_not_modified_repr(self):
        response = HttpResponseNotModified()
        self.assertEqual(repr(response), '<HttpResponseNotModified status_code=304>')

    def test_not_allowed(self):
        response = HttpResponseNotAllowed(['GET'])
        self.assertEqual(response.status_code, 405)
        # Standard HttpResponse init args can be used
        response = HttpResponseNotAllowed(['GET'], content='Only the GET method is allowed', content_type='text/html')
        self.assertContains(response, 'Only the GET method is allowed', status_code=405)

    def test_not_allowed_repr(self):
        response = HttpResponseNotAllowed(['GET', 'OPTIONS'], content_type='text/plain')
        expected = '<HttpResponseNotAllowed [GET, OPTIONS] status_code=405, "text/plain">'
        self.assertEqual(repr(response), expected)

    def test_not_allowed_repr_no_content_type(self):
        response = HttpResponseNotAllowed(('GET', 'POST'))
        del response.headers['Content-Type']
        self.assertEqual(repr(response), '<HttpResponseNotAllowed [GET, POST] status_code=405>')


class JsonResponseTests(SimpleTestCase):
    def test_json_response_non_ascii(self):
        data = {'key': 'łóżko'}
        response = JsonResponse(data)
        self.assertEqual(json.loads(response.content.decode()), data)

    def test_json_response_raises_type_error_with_default_setting(self):
        with self.assertRaisesMessage(
            TypeError,
            'In order to allow non-dict objects to be serialized set the '
            'safe parameter to False'
        ):
            JsonResponse([1, 2, 3])

    def test_json_response_text(self):
        response = JsonResponse('foobar', safe=False)
        self.assertEqual(json.loads(response.content.decode()), 'foobar')

    def test_json_response_list(self):
        response = JsonResponse(['foo', 'bar'], safe=False)
        self.assertEqual(json.loads(response.content.decode()), ['foo', 'bar'])

    def test_json_response_uuid(self):
        u = uuid.uuid4()
        response = JsonResponse(u, safe=False)
        self.assertEqual(json.loads(response.content.decode()), str(u))

    def test_json_response_custom_encoder(self):
        class CustomDjangoJSONEncoder(DjangoJSONEncoder):
            def encode(self, o):
                return json.dumps({'foo': 'bar'})

        response = JsonResponse({}, encoder=CustomDjangoJSONEncoder)
        self.assertEqual(json.loads(response.content.decode()), {'foo': 'bar'})

    def test_json_response_passing_arguments_to_json_dumps(self):
        response = JsonResponse({'foo': 'bar'}, json_dumps_params={'indent': 2})
        self.assertEqual(response.content.decode(), '{\n  "foo": "bar"\n}')


class StreamingHttpResponseTests(SimpleTestCase):
    def test_streaming_response(self):
        r = StreamingHttpResponse(iter(['hello', 'world']))

        # iterating over the response itself yields bytestring chunks.
        chunks = list(r)
        self.assertEqual(chunks, [b'hello', b'world'])
        for chunk in chunks:
            self.assertIsInstance(chunk, bytes)

        # and the response can only be iterated once.
        self.assertEqual(list(r), [])

        # even when a sequence that can be iterated many times, like a list,
        # is given as content.
        r = StreamingHttpResponse(['abc', 'def'])
        self.assertEqual(list(r), [b'abc', b'def'])
        self.assertEqual(list(r), [])

        # iterating over strings still yields bytestring chunks.
        r.streaming_content = iter(['hello', 'café'])
        chunks = list(r)
        # '\xc3\xa9' == unichr(233).encode()
        self.assertEqual(chunks, [b'hello', b'caf\xc3\xa9'])
        for chunk in chunks:
            self.assertIsInstance(chunk, bytes)

        # streaming responses don't have a `content` attribute.
        self.assertFalse(hasattr(r, 'content'))

        # and you can't accidentally assign to a `content` attribute.
        with self.assertRaises(AttributeError):
            r.content = 'xyz'

        # but they do have a `streaming_content` attribute.
        self.assertTrue(hasattr(r, 'streaming_content'))

        # that exists so we can check if a response is streaming, and wrap or
        # replace the content iterator.
        r.streaming_content = iter(['abc', 'def'])
        r.streaming_content = (chunk.upper() for chunk in r.streaming_content)
        self.assertEqual(list(r), [b'ABC', b'DEF'])

        # coercing a streaming response to bytes doesn't return a complete HTTP
        # message like a regular response does. it only gives us the headers.
        r = StreamingHttpResponse(iter(['hello', 'world']))
        self.assertEqual(bytes(r), b'Content-Type: text/html; charset=utf-8')

        # and this won't consume its content.
        self.assertEqual(list(r), [b'hello', b'world'])

        # additional content cannot be written to the response.
        r = StreamingHttpResponse(iter(['hello', 'world']))
        with self.assertRaises(Exception):
            r.write('!')

        # and we can't tell the current position.
        with self.assertRaises(Exception):
            r.tell()

        r = StreamingHttpResponse(iter(['hello', 'world']))
        self.assertEqual(r.getvalue(), b'helloworld')


class FileCloseTests(SimpleTestCase):

    def setUp(self):
        # Disable the request_finished signal during this test
        # to avoid interfering with the database connection.
        request_finished.disconnect(close_old_connections)

    def tearDown(self):
        request_finished.connect(close_old_connections)

    def test_response(self):
        filename = os.path.join(os.path.dirname(__file__), 'abc.txt')

        # file isn't closed until we close the response.
        file1 = open(filename)
        r = HttpResponse(file1)
        self.assertTrue(file1.closed)
        r.close()

        # when multiple file are assigned as content, make sure they are all
        # closed with the response.
        file1 = open(filename)
        file2 = open(filename)
        r = HttpResponse(file1)
        r.content = file2
        self.assertTrue(file1.closed)
        self.assertTrue(file2.closed)

    def test_streaming_response(self):
        filename = os.path.join(os.path.dirname(__file__), 'abc.txt')

        # file isn't closed until we close the response.
        file1 = open(filename)
        r = StreamingHttpResponse(file1)
        self.assertFalse(file1.closed)
        r.close()
        self.assertTrue(file1.closed)

        # when multiple file are assigned as content, make sure they are all
        # closed with the response.
        file1 = open(filename)
        file2 = open(filename)
        r = StreamingHttpResponse(file1)
        r.streaming_content = file2
        self.assertFalse(file1.closed)
        self.assertFalse(file2.closed)
        r.close()
        self.assertTrue(file1.closed)
        self.assertTrue(file2.closed)


class CookieTests(unittest.TestCase):
    def test_encode(self):
        """Semicolons and commas are encoded."""
        c = SimpleCookie()
        c['test'] = "An,awkward;value"
        self.assertNotIn(";", c.output().rstrip(';'))  # IE compat
        self.assertNotIn(",", c.output().rstrip(';'))  # Safari compat

    def test_decode(self):
        """Semicolons and commas are decoded."""
        c = SimpleCookie()
        c['test'] = "An,awkward;value"
        c2 = SimpleCookie()
        c2.load(c.output()[12:])
        self.assertEqual(c['test'].value, c2['test'].value)
        c3 = parse_cookie(c.output()[12:])
        self.assertEqual(c['test'].value, c3['test'])

    def test_nonstandard_keys(self):
        """
        A single non-standard cookie name doesn't affect all cookies (#13007).
        """
        self.assertIn('good_cookie', parse_cookie('good_cookie=yes;bad:cookie=yes'))

    def test_repeated_nonstandard_keys(self):
        """
        A repeated non-standard name doesn't affect all cookies (#15852).
        """
        self.assertIn('good_cookie', parse_cookie('a:=b; a:=c; good_cookie=yes'))

    def test_python_cookies(self):
        """
        Test cases copied from Python's Lib/test/test_http_cookies.py
        """
        self.assertEqual(parse_cookie('chips=ahoy; vienna=finger'), {'chips': 'ahoy', 'vienna': 'finger'})
        # Here parse_cookie() differs from Python's cookie parsing in that it
        # treats all semicolons as delimiters, even within quotes.
        self.assertEqual(
            parse_cookie('keebler="E=mc2; L=\\"Loves\\"; fudge=\\012;"'),
            {'keebler': '"E=mc2', 'L': '\\"Loves\\"', 'fudge': '\\012', '': '"'}
        )
        # Illegal cookies that have an '=' char in an unquoted value.
        self.assertEqual(parse_cookie('keebler=E=mc2'), {'keebler': 'E=mc2'})
        # Cookies with ':' character in their name.
        self.assertEqual(parse_cookie('key:term=value:term'), {'key:term': 'value:term'})
        # Cookies with '[' and ']'.
        self.assertEqual(parse_cookie('a=b; c=[; d=r; f=h'), {'a': 'b', 'c': '[', 'd': 'r', 'f': 'h'})

    def test_cookie_edgecases(self):
        # Cookies that RFC6265 allows.
        self.assertEqual(parse_cookie('a=b; Domain=example.com'), {'a': 'b', 'Domain': 'example.com'})
        # parse_cookie() has historically kept only the last cookie with the
        # same name.
        self.assertEqual(parse_cookie('a=b; h=i; a=c'), {'a': 'c', 'h': 'i'})

    def test_invalid_cookies(self):
        """
        Cookie strings that go against RFC6265 but browsers will send if set
        via document.cookie.
        """
        # Chunks without an equals sign appear as unnamed values per
        # https://bugzilla.mozilla.org/show_bug.cgi?id=169091
        self.assertIn('django_language', parse_cookie('abc=def; unnamed; django_language=en'))
        # Even a double quote may be an unnamed value.
        self.assertEqual(parse_cookie('a=b; "; c=d'), {'a': 'b', '': '"', 'c': 'd'})
        # Spaces in names and values, and an equals sign in values.
        self.assertEqual(parse_cookie('a b c=d e = f; gh=i'), {'a b c': 'd e = f', 'gh': 'i'})
        # More characters the spec forbids.
        self.assertEqual(parse_cookie('a   b,c<>@:/[]?{}=d  "  =e,f g'), {'a   b,c<>@:/[]?{}': 'd  "  =e,f g'})
        # Unicode characters. The spec only allows ASCII.
        self.assertEqual(parse_cookie('saint=André Bessette'), {'saint': 'André Bessette'})
        # Browsers don't send extra whitespace or semicolons in Cookie headers,
        # but parse_cookie() should parse whitespace the same way
        # document.cookie parses whitespace.
        self.assertEqual(parse_cookie('  =  b  ;  ;  =  ;   c  =  ;  '), {'': 'b', 'c': ''})

    def test_samesite(self):
        c = SimpleCookie('name=value; samesite=lax; httponly')
        self.assertEqual(c['name']['samesite'], 'lax')
        self.assertIn('SameSite=lax', c.output())

    def test_httponly_after_load(self):
        c = SimpleCookie()
        c.load("name=val")
        c['name']['httponly'] = True
        self.assertTrue(c['name']['httponly'])

    def test_load_dict(self):
        c = SimpleCookie()
        c.load({'name': 'val'})
        self.assertEqual(c['name'].value, 'val')

    def test_pickle(self):
        rawdata = 'Customer="WILE_E_COYOTE"; Path=/acme; Version=1'
        expected_output = 'Set-Cookie: %s' % rawdata

        C = SimpleCookie()
        C.load(rawdata)
        self.assertEqual(C.output(), expected_output)

        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            C1 = pickle.loads(pickle.dumps(C, protocol=proto))
            self.assertEqual(C1.output(), expected_output)


class HttpResponseHeadersTestCase(SimpleTestCase):
    """Headers by treating HttpResponse like a dictionary."""
    def test_headers(self):
        response = HttpResponse()
        response['X-Foo'] = 'bar'
        self.assertEqual(response['X-Foo'], 'bar')
        self.assertEqual(response.headers['X-Foo'], 'bar')
        self.assertIn('X-Foo', response)
        self.assertIs(response.has_header('X-Foo'), True)
        del response['X-Foo']
        self.assertNotIn('X-Foo', response)
        self.assertNotIn('X-Foo', response.headers)
        # del doesn't raise a KeyError on nonexistent headers.
        del response['X-Foo']

    def test_headers_as_iterable_of_tuple_pairs(self):
        response = HttpResponse(headers=(('X-Foo', 'bar'),))
        self.assertEqual(response['X-Foo'], 'bar')

    def test_headers_bytestring(self):
        response = HttpResponse()
        response['X-Foo'] = b'bar'
        self.assertEqual(response['X-Foo'], 'bar')
        self.assertEqual(response.headers['X-Foo'], 'bar')

    def test_newlines_in_headers(self):
        response = HttpResponse()
        with self.assertRaises(BadHeaderError):
            response['test\rstr'] = 'test'
        with self.assertRaises(BadHeaderError):
            response['test\nstr'] = 'test'