def finish_content(self):
"""Ensure headers and content have both been sent"""
if not self.headers_sent:
- self.headers['Content-Length'] = "0"
+ # Only zero Content-Length if not set by the application (so
+ # that HEAD requests can be satisfied properly, see #3839)
+ self.headers.setdefault('Content-Length', "0")
self.send_headers()
else:
pass # XXX check if content-length was too short?