Replaced parse_header with parse_header_parameters. (#8556)

Add a backwards compatibility shim for Django versions that have no (or an incompatible)
django.utils.http.parse_header_parameters implementation.

Thanks to Shai Berger for review. 

Co-authored-by: Jaap Roes <jroes@leukeleu.nl>

rest_framework/compat.py

@@ -2,6 +2,7 @@
 The `compat` module provides support for backwards compatibility with older
 versions of Django/Python, and compatibility wrappers around optional packages.
 """
+import django
 from django.conf import settings
 from django.views.generic import View
 
@@ -152,6 +153,30 @@ else:
         return False
 
 
+if django.VERSION >= (4, 2):
+    # Django 4.2+: use the stock parse_header_parameters function
+    # Note: Django 4.1 also has an implementation of parse_header_parameters
+    #       which is slightly different from the one in 4.2, it needs
+    #       the compatibility shim as well.
+    from django.utils.http import parse_header_parameters
+else:
+    # Django <= 4.1: create a compatibility shim for parse_header_parameters
+    from django.http.multipartparser import parse_header
+
+    def parse_header_parameters(line):
+        # parse_header works with bytes, but parse_header_parameters
+        # works with strings. Call encode to convert the line to bytes.
+        main_value_pair, params = parse_header(line.encode())
+        return main_value_pair, {
+            # parse_header will convert *some* values to string.
+            # parse_header_parameters converts *all* values to string.
+            # Make sure all values are converted by calling decode on
+            # any remaining non-string values.
+            k: v if isinstance(v, str) else v.decode()
+            for k, v in params.items()
+        }
+
+
 # `separators` argument to `json.dumps()` differs between 2.x and 3.x
 # See: https://bugs.python.org/issue22767
 SHORT_SEPARATORS = (',', ':')

rest_framework/negotiation.py

@@ -4,7 +4,7 @@ incoming request.  Typically this will be based on the request's Accept header.
 """
 from django.http import Http404
 
-from rest_framework import HTTP_HEADER_ENCODING, exceptions
+from rest_framework import exceptions
 from rest_framework.settings import api_settings
 from rest_framework.utils.mediatypes import (
     _MediaType, media_type_matches, order_by_precedence
@@ -64,9 +64,11 @@ class DefaultContentNegotiation(BaseContentNegotiation):
                             # Accepted media type is 'application/json'
                             full_media_type = ';'.join(
                                 (renderer.media_type,) +
-                                tuple('{}={}'.format(
-                                    key, value.decode(HTTP_HEADER_ENCODING))
-                                    for key, value in media_type_wrapper.params.items()))
+                                tuple(
+                                    '{}={}'.format(key, value)
+                                    for key, value in media_type_wrapper.params.items()
+                                )
+                            )
                             return renderer, full_media_type
                         else:
                             # Eg client requests 'application/json; indent=8'

rest_framework/parsers.py

@@ -5,7 +5,6 @@ They give us a generic way of being able to handle various media types
 on the request, such as form content or json encoded data.
 """
 import codecs
-from urllib import parse
 
 from django.conf import settings
 from django.core.files.uploadhandler import StopFutureHandlers
@@ -13,10 +12,10 @@ from django.http import QueryDict
 from django.http.multipartparser import ChunkIter
 from django.http.multipartparser import \
     MultiPartParser as DjangoMultiPartParser
-from django.http.multipartparser import MultiPartParserError, parse_header
-from django.utils.encoding import force_str
+from django.http.multipartparser import MultiPartParserError
 
 from rest_framework import renderers
+from rest_framework.compat import parse_header_parameters
 from rest_framework.exceptions import ParseError
 from rest_framework.settings import api_settings
 from rest_framework.utils import json
@@ -201,23 +200,10 @@ class FileUploadParser(BaseParser):
 
         try:
             meta = parser_context['request'].META
-            disposition = parse_header(meta['HTTP_CONTENT_DISPOSITION'].encode())
-            filename_parm = disposition[1]
-            if 'filename*' in filename_parm:
-                return self.get_encoded_filename(filename_parm)
-            return force_str(filename_parm['filename'])
+            disposition, params = parse_header_parameters(meta['HTTP_CONTENT_DISPOSITION'])
+            if 'filename*' in params:
+                return params['filename*']
+            else:
+                return params['filename']
         except (AttributeError, KeyError, ValueError):
             pass
-
-    def get_encoded_filename(self, filename_parm):
-        """
-        Handle encoded filenames per RFC6266. See also:
-        https://tools.ietf.org/html/rfc2231#section-4
-        """
-        encoded_filename = force_str(filename_parm['filename*'])
-        try:
-            charset, lang, filename = encoded_filename.split('\'', 2)
-            filename = parse.unquote(filename)
-        except (ValueError, LookupError):
-            filename = force_str(filename_parm['filename'])
-        return filename

rest_framework/renderers.py

@@ -14,7 +14,6 @@ from django import forms
 from django.conf import settings
 from django.core.exceptions import ImproperlyConfigured
 from django.core.paginator import Page
-from django.http.multipartparser import parse_header
 from django.template import engines, loader
 from django.urls import NoReverseMatch
 from django.utils.html import mark_safe
@@ -22,7 +21,7 @@ from django.utils.html import mark_safe
 from rest_framework import VERSION, exceptions, serializers, status
 from rest_framework.compat import (
     INDENT_SEPARATORS, LONG_SEPARATORS, SHORT_SEPARATORS, coreapi, coreschema,
-    pygments_css, yaml
+    parse_header_parameters, pygments_css, yaml
 )
 from rest_framework.exceptions import ParseError
 from rest_framework.request import is_form_media_type, override_method
@@ -72,7 +71,7 @@ class JSONRenderer(BaseRenderer):
             # If the media type looks like 'application/json; indent=4',
             # then pretty print the result.
             # Note that we coerce `indent=0` into `indent=None`.
-            base_media_type, params = parse_header(accepted_media_type.encode('ascii'))
+            base_media_type, params = parse_header_parameters(accepted_media_type)
             try:
                 return zero_as_none(max(min(int(params['indent']), 8), 0))
             except (KeyError, ValueError, TypeError):

rest_framework/request.py

@@ -14,11 +14,11 @@ from contextlib import contextmanager
 
 from django.conf import settings
 from django.http import HttpRequest, QueryDict
-from django.http.multipartparser import parse_header
 from django.http.request import RawPostDataException
 from django.utils.datastructures import MultiValueDict
 
-from rest_framework import HTTP_HEADER_ENCODING, exceptions
+from rest_framework import exceptions
+from rest_framework.compat import parse_header_parameters
 from rest_framework.settings import api_settings
 
 
@@ -26,7 +26,7 @@ def is_form_media_type(media_type):
     """
     Return True if the media type is a valid form media type.
     """
-    base_media_type, params = parse_header(media_type.encode(HTTP_HEADER_ENCODING))
+    base_media_type, params = parse_header_parameters(media_type)
     return (base_media_type == 'application/x-www-form-urlencoded' or
             base_media_type == 'multipart/form-data')
 

rest_framework/utils/mediatypes.py

@@ -3,9 +3,7 @@ Handling of media types, as found in HTTP Content-Type and Accept headers.
 
 See https://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.7
 """
-from django.http.multipartparser import parse_header
-
-from rest_framework import HTTP_HEADER_ENCODING
+from rest_framework.compat import parse_header_parameters
 
 
 def media_type_matches(lhs, rhs):
@@ -46,7 +44,7 @@ def order_by_precedence(media_type_lst):
 class _MediaType:
     def __init__(self, media_type_str):
         self.orig = '' if (media_type_str is None) else media_type_str
-        self.full_type, self.params = parse_header(self.orig.encode(HTTP_HEADER_ENCODING))
+        self.full_type, self.params = parse_header_parameters(self.orig)
         self.main_type, sep, self.sub_type = self.full_type.partition('/')
 
     def match(self, other):
@@ -79,5 +77,5 @@ class _MediaType:
     def __str__(self):
         ret = "%s/%s" % (self.main_type, self.sub_type)
         for key, val in self.params.items():
-            ret += "; %s=%s" % (key, val.decode('ascii'))
+            ret += "; %s=%s" % (key, val)
         return ret