add remote_addr property for proxy fix

sanic/request.py

@@ -45,7 +45,7 @@ class Request(dict):
     __slots__ = (
         'app', 'headers', 'version', 'method', '_cookies', 'transport',
         'body', 'parsed_json', 'parsed_args', 'parsed_form', 'parsed_files',
-        '_ip', '_parsed_url', 'uri_template', 'stream'
+        '_ip', '_parsed_url', 'uri_template', 'stream', '_remote_addr'
     )
 
     def __init__(self, url_bytes, headers, version, method, transport):
@@ -142,7 +142,7 @@ class Request(dict):
     @property
     def cookies(self):
         if self._cookies is None:
-            cookie = self.headers.get('Cookie') or self.headers.get('cookie')
+            cookie = self.headers.get('Cookie')
             if cookie is not None:
                 cookies = SimpleCookie()
                 cookies.load(cookie)
@@ -159,6 +159,23 @@ class Request(dict):
                         (None, None))
         return self._ip
 
+    @property
+    def remote_addr(self):
+        """Attempt to return the original client ip based on X-Forwarded-For.
+
+        :return: original client ip.
+        """
+        if not hasattr(self, '_remote_addr'):
+            forwarded_for = self.headers.get('X-Forwarded-For', '').split(',')
+            remote_addrs = [
+                addr for addr in [addr.strip() for addr in forwarded_for] if addr
+            ]
+            if len(remote_addrs) > 0:
+                self._remote_addr = remote_addrs[0]
+            else:
+                self._remote_addr = ''
+        return self._remote_addr
+
     @property
     def scheme(self):
         if self.app.websocket_enabled \

tests/test_requests.py

@@ -211,6 +211,32 @@ def test_content_type():
     assert response.text == 'application/json'
 
 
+def test_remote_addr():
+    app = Sanic('test_content_type')
+
+    @app.route('/')
+    async def handler(request):
+        return text(request.remote_addr)
+
+    headers = {
+        'X-Forwarded-For': '127.0.0.1, 127.0.1.2'
+    }
+    request, response = app.test_client.get('/', headers=headers)
+    assert request.remote_addr == '127.0.0.1'
+    assert response.text == '127.0.0.1'
+
+    request, response = app.test_client.get('/')
+    assert request.remote_addr == ''
+    assert response.text == ''
+
+    headers = {
+        'X-Forwarded-For': '127.0.0.1, ,   ,,127.0.1.2'
+    }
+    request, response = app.test_client.get('/', headers=headers)
+    assert request.remote_addr == '127.0.0.1'
+    assert response.text == '127.0.0.1'
+
+
 def test_match_info():
     app = Sanic('test_match_info')
 
@@ -259,6 +285,7 @@ def test_post_form_urlencoded():
 
     assert request.form.get('test') == 'OK'
 
+
 @pytest.mark.parametrize(
     'payload', [
         '------sanic\r\n' \