Corrected --proxy-headers client ip/host when using a unix socket (#636)

* Added AF_UNIX type socket to get client filled

* Removed travis debug

* Added travis verbose pytest for windows fail check

* Added travis verbose pytest for windows fail check

* No more tests output in travis now it's fixed on windows

* Useing a top level constant

* Lint

uvicorn/protocols/utils.py

@@ -1,6 +1,11 @@
 import socket
 import urllib
 
+if hasattr(socket, "AF_UNIX"):
+    SUPPORTED_SOCKET_FAMILIES = (socket.AF_INET, socket.AF_INET6, socket.AF_UNIX)
+else:
+    SUPPORTED_SOCKET_FAMILIES = (socket.AF_INET, socket.AF_INET6)
+
 
 def get_remote_addr(transport):
     socket_info = transport.get_extra_info("socket")
@@ -15,8 +20,9 @@ def get_remote_addr(transport):
         else:
             family = socket_info.family
 
-        if family in (socket.AF_INET, socket.AF_INET6):
+        if family in SUPPORTED_SOCKET_FAMILIES:
             return (str(info[0]), int(info[1]))
+
         return None
     info = transport.get_extra_info("peername")
     if info is not None and isinstance(info, (list, tuple)) and len(info) == 2:
@@ -29,7 +35,7 @@ def get_local_addr(transport):
     if socket_info is not None:
         info = socket_info.getsockname()
         family = socket_info.family
-        if family in (socket.AF_INET, socket.AF_INET6):
+        if family in SUPPORTED_SOCKET_FAMILIES:
             return (str(info[0]), int(info[1]))
         return None
     info = transport.get_extra_info("sockname")