Fixed #20147 -- Added HttpRequest.headers.

1 files changed, 29 insertions, 1 deletions

diff --git a/django/http/request.py b/django/http/request.py
index 7dc758d268..02a127d664 100644
--- a/django/http/request.py
+++ b/django/http/request.py
@@ -12,7 +12,9 @@ from django.core.exceptions import (
 )
 from django.core.files import uploadhandler
 from django.http.multipartparser import MultiPartParser, MultiPartParserError
-from django.utils.datastructures import ImmutableList, MultiValueDict
+from django.utils.datastructures import (
+    CaseInsensitiveMapping, ImmutableList, MultiValueDict,
+)
 from django.utils.deprecation import RemovedInDjango30Warning
 from django.utils.encoding import escape_uri_path, iri_to_uri
 from django.utils.functional import cached_property
@@ -65,6 +67,10 @@ class HttpRequest:
             return '<%s>' % self.__class__.__name__
         return '<%s: %s %r>' % (self.__class__.__name__, self.method, self.get_full_path())
 
+    @cached_property
+    def headers(self):
+        return HttpHeaders(self.META)
+
     def _get_raw_host(self):
         """
         Return the HTTP host using the environment or request headers. Skip
@@ -359,6 +365,28 @@ class HttpRequest:
         return list(self)
 
 
+class HttpHeaders(CaseInsensitiveMapping):
+    HTTP_PREFIX = 'HTTP_'
+    # PEP 333 gives two headers which aren't prepended with HTTP_.
+    UNPREFIXED_HEADERS = {'CONTENT_TYPE', 'CONTENT_LENGTH'}
+
+    def __init__(self, environ):
+        headers = {}
+        for header, value in environ.items():
+            name = self.parse_header_name(header)
+            if name:
+                headers[name] = value
+        super().__init__(headers)
+
+    @classmethod
+    def parse_header_name(cls, header):
+        if header.startswith(cls.HTTP_PREFIX):
+            header = header[len(cls.HTTP_PREFIX):]
+        elif header not in cls.UNPREFIXED_HEADERS:
+            return None
+        return header.replace('_', '-').title()
+
+
 class QueryDict(MultiValueDict):
     """
     A specialized MultiValueDict which represents a query string.