Omit Content-Length on chunked transfer

Content-Length and Transfer-Encoding conflict according to the HTTP
spec. This fixes bug 981332.

[ This is backported from 223fbee ]

Change-Id: I62f2bcabd9712361dd8837e39a577c4add052d0f

glance/common/client.py

@@ -198,8 +198,12 @@ def _do_request(self, method, action, body=None, headers=None,
                 # Chunk it, baby...
                 c.putrequest(method, action)
 
+                # According to HTTP/1.1, Content-Length and Transfer-Encoding
+                # conflict.
                 for header, value in headers.items():
-                    c.putheader(header, value)
+                    if header.lower() != 'content-length':
+                        c.putheader(header, value)
+
                 c.putheader('Transfer-Encoding', 'chunked')
                 c.endheaders()
 

glance/tests/stubs.py

@@ -95,7 +95,7 @@ def connect(self):
         def close(self):
             return True
 
-        def request(self, method, url, body=None, headers={}):
+        def request(self, method, url, body=None, headers=None):
             self.req = webob.Request.blank("/" + url.lstrip("/"))
             self.req.method = method
             if headers:
@@ -138,15 +138,18 @@ def putheader(self, key, value):
             self.req.headers[key] = value
 
         def endheaders(self):
-            pass
+            hl = [i.lower() for i in self.req.headers.keys()]
+            assert not ('content-length' in hl and
+                        'transfer-encoding' in hl), \
+                'Content-Length and Transfer-Encoding are mutually exclusive'
 
         def send(self, data):
             # send() is called during chunked-transfer encoding, and
             # data is of the form %x\r\n%s\r\n. Strip off the %x and
             # only write the actual data in tests.
             self.req.body += data.split("\r\n")[1]
 
-        def request(self, method, url, body=None, headers={}):
+        def request(self, method, url, body=None, headers=None):
             self.req = webob.Request.blank("/" + url.lstrip("/"))
             self.req.method = method
             if headers: