diff mercurial/hgweb/server.py @ 18354:cf5c76017e11

serve: use chunked encoding in hgweb responses

'hg serve' used to close connections when sending a response with unknown
length ... such as a bundle or archive.

Now chunked encoding will be used for responses with unknown length, and the
connection do thus not have to be closed to indicate the end of the response.

Chunked encoding is only used if the length is unknown, if the connection
wouldn't be closed for other reasons, AND if it is a HTTP 1.1 request.

This will not benefit other users of hgweb ... but it can serve as an example
that it can be done.

--- a/mercurial/hgweb/server.py	Tue Jan 15 01:10:08 2013 +0100
+++ b/mercurial/hgweb/server.py	Tue Jan 15 01:10:08 2013 +0100
@@ -133,10 +133,12 @@
         self.saved_headers = []
         self.sent_headers = False
         self.length = None
+        self._chunked = None
         for chunk in self.server.application(env, self._start_response):
             self._write(chunk)
         if not self.sent_headers:
             self.send_headers()
+        self._done()
 
     def send_headers(self):
         if not self.saved_status:
@@ -145,16 +147,19 @@
         saved_status = self.saved_status.split(None, 1)
         saved_status[0] = int(saved_status[0])
         self.send_response(*saved_status)
-        should_close = True
+        self.length = None
+        self._chunked = False
         for h in self.saved_headers:
             self.send_header(*h)
             if h[0].lower() == 'content-length':
-                should_close = False
                 self.length = int(h[1])
-        # The value of the Connection header is a list of case-insensitive
-        # tokens separated by commas and optional whitespace.
-        if should_close:
-            self.send_header('Connection', 'close')
+        if self.length is None:
+            self._chunked = (not self.close_connection and
+                             self.request_version == "HTTP/1.1")
+            if self._chunked:
+                self.send_header('Transfer-Encoding', 'chunked')
+            else:
+                self.send_header('Connection', 'close')
         self.end_headers()
         self.sent_headers = True
 
@@ -177,9 +182,16 @@
                 raise AssertionError("Content-length header sent, but more "
                                      "bytes than specified are being written.")
             self.length = self.length - len(data)
+        elif self._chunked and data:
+            data = '%x\r\n%s\r\n' % (len(data), data)
         self.wfile.write(data)
         self.wfile.flush()
 
+    def _done(self):
+        if self._chunked:
+            self.wfile.write('0\r\n\r\n')
+            self.wfile.flush()
+
 class _httprequesthandleropenssl(_httprequesthandler):
     """HTTPS handler based on pyOpenSSL"""