From: Ben Darnell <ben@bendarnell.com>
Date: Fri, 27 Apr 2018 14:14:18 +0000 (-0400)
Subject: web: Add RequestHandler.detach
X-Git-Tag: v5.1.0b1~21^2~8
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=0200fc85b7b9eb0debd1a17c019a2164d32af6c6;p=thirdparty%2Ftornado.git

web: Add RequestHandler.detach

This method eliminates the need to use the asynchronous decorator on
handlers that may call detach.
---

diff --git a/tornado/test/simple_httpclient_test.py b/tornado/test/simple_httpclient_test.py
index 818fdad83..09038710d 100644
--- a/tornado/test/simple_httpclient_test.py
+++ b/tornado/test/simple_httpclient_test.py
@@ -57,9 +57,8 @@ class HangHandler(RequestHandler):
 
 
 class ContentLengthHandler(RequestHandler):
-    @asynchronous
     def get(self):
-        self.stream = self.request.connection.detach()
+        self.stream = self.detach()
         IOLoop.current().spawn_callback(self.write_response)
 
     @gen.coroutine
@@ -107,13 +106,12 @@ class HostEchoHandler(RequestHandler):
 
 
 class NoContentLengthHandler(RequestHandler):
-    @asynchronous
     def get(self):
         if self.request.version.startswith('HTTP/1'):
             # Emulate the old HTTP/1.0 behavior of returning a body with no
             # content-length.  Tornado handles content-length at the framework
             # level so we have to go around it.
-            stream = self.request.connection.detach()
+            stream = self.detach()
             stream.write(b"HTTP/1.0 200 OK\r\n\r\n"
                          b"hello")
             stream.close()
diff --git a/tornado/web.py b/tornado/web.py
index 1c077fd21..888dc5431 100644
--- a/tornado/web.py
+++ b/tornado/web.py
@@ -1022,6 +1022,20 @@ class RequestHandler(object):
         self.on_finish()
         self._break_cycles()
 
+    def detach(self):
+        """Take control of the underlying stream.
+
+        Returns the underlying `.IOStream` object and stops all
+        further HTTP processing. Intended for implementing protocols
+        like websockets that tunnel over an HTTP handshake.
+
+        This method is only supported when HTTP/1.1 is used.
+
+        .. versionadded:: 5.1
+        """
+        self._finished = True
+        return self.request.connection.detach()
+
     def _break_cycles(self):
         # Break up a reference cycle between this handler and the
         # _ui_module closures to allow for faster GC on CPython.
diff --git a/tornado/websocket.py b/tornado/websocket.py
index 0507a92c6..cc2d4cced 100644
--- a/tornado/websocket.py
+++ b/tornado/websocket.py
@@ -145,7 +145,6 @@ class WebSocketHandler(tornado.web.RequestHandler):
         self.stream = None
         self._on_close_called = False
 
-    @tornado.web.asynchronous
     def get(self, *args, **kwargs):
         self.open_args = args
         self.open_kwargs = kwargs
@@ -481,7 +480,7 @@ class WebSocketHandler(tornado.web.RequestHandler):
                 self, compression_options=self.get_compression_options())
 
     def _attach_stream(self):
-        self.stream = self.request.connection.detach()
+        self.stream = self.detach()
         self.stream.set_close_callback(self.on_connection_close)
         # disable non-WS methods
         for method in ["write", "redirect", "set_header", "set_cookie",